JP2000022266A - Semiconductor light emitting device - Google Patents

Abstract

(57) Abstract: A semiconductor light emitting device that can be formed with a high degree of integration while maintaining a constant temperature difference between an element for measuring temperature and a semiconductor light emitting device, keeping a thermal stress therebetween small. Provide structure. The semiconductor device includes a substrate, a semiconductor layer formed on the substrate, a semiconductor light emitting element formed on the semiconductor layer, and a temperature sensor formed on the semiconductor layer. Semiconductor light emitting device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor light emitting device using a compound semiconductor material, and in particular, to GaN, AlGaN, and InGaN.
And a structure for stably operating a semiconductor light emitting device made of a GaN compound semiconductor such as a GaN compound semiconductor.

[0002]

2. Description of the Related Art In recent years, as a means for realizing a high-density optical disk system, a blue semiconductor laser having a wavelength shorter than that of a conventional GaInAsP-based red laser has been developed. As a blue semiconductor laser, a ZnSe-based or GaN-based semiconductor laser has been confirmed to emit laser at room temperature. However, for example, in the case of GaN-based semiconductor lasers, the threshold current density of lasers that have been announced so far is as high as ³ kA / cm ² or more, which is the laser threshold current density of red lasers.
Several times larger than 1 kA / cm ² . Therefore, the injection current amount for stably obtaining laser oscillation is also typically 10 kA / cm ²
And the power P consumed by non-radiative recombination that does not contribute to light emission also increases. The power consumed by the non-radiative recombination mainly becomes Joule heat, which causes a rise in the temperature of the device, which causes a problem that the device is destroyed.

In order to solve this problem, a semiconductor integrated circuit having a function of integrating a temperature sensor for measuring the temperature of a semiconductor light emitting element on a heat sink and stopping the light emission when the temperature becomes a certain temperature or more is provided. It is known (for example, JP-A-9-83088).

FIG. 36 is a sectional view of a semiconductor light emitting device having such a temperature sensor. A semiconductor light emitting device 1 such as a semiconductor laser and a temperature sensor 2 such as a thermistor are mounted on a heat sink 5 made of copper or aluminum via separate submounts 3 and 4, respectively. The submounts 3 and 4 are made of diamond, alumina, an aluminum nitride film, mica, or silicon rubber. These submounts 3 and 4 are made of an insulator having good thermal conductivity and are formed, for example, with a thickness of 10 to 100 μm.

[0005] The semiconductor light emitting device 1 is made of GaN, AlGaN, InAl or the like.
A thin-film semiconductor light-emitting layer 6 of 10 μm or less made of GaN is formed on a growth substrate 7 made of alumina or spinel by growing in a gas phase or a liquid phase. This semiconductor light emitting device 1
After being epitaxially formed on the growth substrate 7, it is bonded on the submount 3 and mounted on the heat sink 5.

Incidentally, in the GaN-based semiconductor light emitting device 1,
At present, good characteristics can be selected only as a substrate formed of an aluminum oxide film such as sapphire or a substrate using a spinel such as MgAl ₂ O ₄ as an epitaxial growth substrate. The thermal conductivity H of these substrates is 60 Wm ^-1 K ^-1 or less, and Ga
Less than half of 130 Wm ^-1 K ^-1 which is the thermal conductivity of N 2.

As described above, it is difficult to control the p-type GaN-based semiconductor light-emitting device, which is a typical example of a blue laser, to the p-type, and to lower the resistance of the p-type GaN contact layer. Therefore, the power consumption of the series parasitic resistance is large, and the amount of heat generated in the element is very large.

Therefore, when a blue light-emitting device such as a GaN-based device is used in the structure shown in FIG. 36, the thermal resistance of the growth substrate 7 is large, and the heat generated by the semiconductor light-emitting device 1 is not easily transmitted to the temperature sensor. There is a problem that the temperature of the semiconductor light emitting element 1 cannot be detected by the temperature sensor 2.

Here, how much heat generated by the semiconductor light emitting element 1 is not transmitted to the temperature sensor 2 will be estimated. When the current density injected by the semiconductor laser is I, the voltage applied to the laser is V, and the efficiency is η, the power P per unit area consumed as heat is P = IV (1-η
Becomes Here, assuming that the temperature difference between both surfaces of the growth substrate 7 is ΔT, ΔT = P * d / H. The thermal conductivity H of the growth substrate 7 is 60
Wm ^-1 K ^-1 , d is 50 μm or more, efficiency η is 0.4, I is 3 kA / cm
² , If V is 5V, P becomes 1.5kW / cm ² and ΔT becomes 75 ° C or more. Therefore, the temperature sensor 2 measures a temperature lower than the actual temperature of the semiconductor light emitting element 1 by 75 ° C. or more.

Further, since the thermal resistance of the growth substrate 7 is large, heat radiation from the thin film semiconductor light emitting layer 6 through the growth substrate 7 (heat radiation from the side and top surfaces of the semiconductor light emitting element 1)
The heat radiation from the thin film semiconductor light emitting layer 6 through the growth substrate 7 cannot be ignored. For this reason, when the temperature of the region other than the heat sink 5 changes, the temperature difference between the temperature sensor 2 and the thin film semiconductor light emitting layer 6 changes, and the temperature difference between the temperature sensor 2 and the thin film semiconductor light emitting layer 6 is kept constant. Becomes difficult. Further, since the temperature dependence of the thermal conductivity of the substrate of the temperature sensor 2 and the temperature dependence of the thermal conductivity of the substrate of the semiconductor light emitting element 1 are different, the thermal resistance from the semiconductor light emitting element 1 to the temperature sensor 2 depends on the temperature. In contrast, it is difficult to keep the difference between the temperature of the temperature sensor 2 and the temperature of the thin-film semiconductor light emitting layer 6 constant. Therefore, by estimating a predetermined temperature difference,
When trying to estimate the temperature of the thin film semiconductor light emitting layer 6 from the temperature output of the temperature sensor 2, a measurement error occurs because the temperature difference is not constant.

In addition to the above-mentioned materials having relatively low thermal conductivity, when the thickness of the growth substrate 7 becomes large and the thermal resistance of the growth substrate 7 becomes larger than the thermal resistance of the thin-film semiconductor light emitting layer 6, A similar problem arises and T increases. That is, even if the growth substrate 7 is a semiconductor substrate such as SiC, if the thickness of the growth substrate 7 is four times or more the thickness of the semiconductor layer 6, the thermal resistance of the growth substrate 7 becomes smaller than that of the thin-film semiconductor light emitting layer 6. Since the resistance becomes larger than the resistance, the above problem occurs.

Further, the temperature sensor 2 and the semiconductor light emitting device 1
Are formed separately from each other,
When mounted on the top, misalignment between the temperature sensor 2 and the semiconductor light emitting element 1 occurs. For this reason, the distance from the thin-film semiconductor light emitting layer 6 to the temperature sensor 2 varies, and the thermal resistance between them varies. Therefore, the temperature sensor 2
The difference between the temperature of the temperature sensor 2 and the temperature of the thin film semiconductor light emitting layer 6 is difficult to keep constant. Further, the temperature sensor 2
Since the semiconductor light emitting device 1 and the semiconductor light emitting device 1 are separately formed, it is difficult to improve their integration.

[0013]

As described above, in the conventional semiconductor light emitting device structure, the temperature sensor 2 for measuring the temperature and the semiconductor light emitting device 1 are separately formed. For this reason, when the thermal resistance of the substrate used for growing the semiconductor light emitting device 1 for crystal growth is large, the temperature of the temperature sensor 2 and the temperature of the semiconductor light emitting device 1 are greatly different. There was a problem that measurement was not possible.

Also, it is difficult to keep the difference between the actual temperature of the semiconductor light emitting element 1 and the temperature of the temperature sensor constant,
There has been a problem that the temperature of the semiconductor light emitting element 1 cannot be estimated by estimating the temperature difference in advance.

Further, since the semiconductor light emitting device 1 and the temperature sensor 2 are separately formed, there is a problem that it is difficult to increase the degree of integration of the semiconductor light emitting device. The present invention has been made in order to solve the above problems, and keeps the temperature difference between the element for measuring temperature and the semiconductor light emitting element constant, keeps the thermal stress between them small, and achieves high integration. It is an object of the present invention to provide a semiconductor light-emitting element that can be formed at different temperatures.

[0016]

To achieve the above object, the present invention provides a substrate, a semiconductor layer formed on the substrate, a semiconductor light emitting device formed on the semiconductor layer,
And a temperature sensor formed on the semiconductor layer.

The present invention also provides a semiconductor light emitting device, wherein the temperature sensor is an impedance element whose resistance changes with temperature. The present invention also provides a semiconductor light emitting device, wherein the substrate is an insulator.

Further, the present invention provides a semiconductor light emitting device wherein the thermal conductivity of the insulator substrate is smaller than that of the semiconductor layer. The present invention also provides a semiconductor light emitting device, wherein the insulator substrate includes an aluminum oxide film, and the semiconductor includes gallium nitrogen or ZnSe.

Further, the present invention provides a semiconductor device, wherein the semiconductor contains gallium nitrogen or ZnSe, and the semiconductor layer is formed on the substrate via silicon carbide.

Further, according to the present invention, the quotient obtained by dividing the thermal conductivity of the silicon carbide by its film thickness is obtained by dividing the thermal conductivity of the semiconductor layer by the distance of the interface from the semiconductor light emitting portion to the silicon carbide. And a semiconductor light-emitting device characterized by being smaller than the above.

According to the present invention, a first conductive type first semiconductor layer formed on an insulator substrate and a second conductive type different from the first conductive type formed on the first semiconductor layer are provided. A second semiconductor layer, a semiconductor light emitting device formed from the first semiconductor layer and the second semiconductor layer, a first electrode formed on the second semiconductor layer, and the first semiconductor A semiconductor light emitting device comprising a second electrode and a third electrode formed on a layer, wherein a resistance between the second electrode and the third electrode changes with temperature.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a sectional view of a semiconductor light emitting device according to a first embodiment of the present invention, and FIG. 2 is a top view thereof. FIG.
Shows a cross-sectional view in the AA 'direction in FIG.

As shown in FIG. 1, a submount 3 and an insulator substrate (growth substrate) 7 are formed on a heat sink 5. The second conductivity type semiconductor layer 20 is formed on the insulator substrate 7. The semiconductor light emitting element 1 is formed on the left side, and the temperature sensor 2 is formed on the right side, using the second conductivity type semiconductor layer 20 as a common base.

The semiconductor light emitting device 1 includes a second conductivity type semiconductor carrier barrier layer 19, a second conductivity type semiconductor light guide layer 18,
A semiconductor active layer 17, a first conductivity type semiconductor light guide layer 16,
A first conductivity type semiconductor carrier barrier layer 15 and a first conductivity type semiconductor contact layer 14 are sequentially laminated to form a high resistance region 2
1 has a current confined structure. 8 is an electrode.

The temperature sensor 2 has a structure in which a conductive thin film 13 is connected in series between an electrode 9 and an electrode 10, and a potential difference can be measured by the electrodes 11 and 12. The main difference between the semiconductor light emitting device shown in this embodiment and the conventional light emitting device shown in FIG. 36 is that the semiconductor light emitting device of this embodiment has a temperature sensor 2 and a semiconductor light emitting device 1 on a semiconductor layer 20. It is being formed in common.

In the semiconductor light emitting device structure of this embodiment, heat generated by the semiconductor light emitting device 1 is transferred to the semiconductor layer 2 having a high thermal conductivity.
By transmitting the temperature directly to the temperature sensor 2 via the “0”, the actual temperature of the semiconductor light emitting device 1 can be measured without causing a temperature drop.

The structure of the semiconductor light emitting device in this embodiment will be described in more detail with reference to specific materials. The heat sink 5 is made of, for example, copper or aluminum,
Alternatively, ceramics such as alumina having high thermal conductivity are used, and the submount 3 can be made of, for example, diamond, silicon carbide, alumina, an aluminum nitride film, mica, or silicon rubber. The submount 3 is made of an insulator having a good thermal conductivity and is formed, for example, with a thickness of 0.1 to 100 μm.

In the conventional semiconductor light emitting device shown in FIG. 36, the submount 3 needs to be an insulator to keep the semiconductor region 20 and the heat sink 5 insulated. However, in the semiconductor light emitting device of the present embodiment, when the growth substrate 7 is an insulator, the submount 3 may be a conductor like silver paste, for example, or may be omitted.

The semiconductor light emitting device 1 is, for example, a GaN-based light emitting device, such as GaN, AlGaN, or InAlGaN.
Consists of These semiconductors are formed on a growth substrate 7 made of, for example, alumina, a C-plane sapphire substrate, or MgO, spinel, or SiC. This growth substrate 7
Is a substrate on which a semiconductor light emitting device 1 such as a semiconductor laser is formed by vapor phase growth or liquid phase growth to form a film.

As a configuration of the semiconductor light emitting device 1, a semiconductor laser having the following laminated structure can be considered.
For example, first, use GaN or AlN as a buffer layer and n-type
The GaN semiconductor layer 20 has a thickness of 0.3 to 10 μm and a growth substrate 7.
Is formed at the top. This n-type GaN semiconductor layer 20
Is formed, for example, by doping silicon from 5 × 10 ¹⁷ to 1 × 10 ¹⁹ cm ⁻³ .

Further, an n-type Al _x Ga ₁ -xN semiconductor carrier barrier layer 19 having a thickness of, for example, 0.1 to 1 μm is formed on the n-type GaN semiconductor layer 20. The composition x of this Al is about 0.1 to 0.5, and when x is increased, the refractive index is reduced and the band gap is widened, so that the semiconductor optical guide layer 16, the semiconductor active layer 17, and the semiconductor optical guide layer 18 have more light and electrons. Can be confined, but the crystallinity deteriorates and the energy for activating the donor level increases, so that the resistance increases. Therefore, it is desirable that x is, for example, about 0.25.

The n-type Al _x Ga ₁ -xN semiconductor carrier barrier layer 19 is formed, for example, by forming silicon from 5 × 10 ¹⁶ to 2 × 10 ¹⁸ cm ^−3.
It is formed by doping. Furthermore, In may be added to the GaN semiconductor light guide layer 18 to make Al _x Ga _{1- xy} In _y N, and y may be 0 <y <0.5, typically,
It may be about 0.05. By adding In as described above, the lifetime of carriers in the semiconductor carrier barrier layer 19 can be extended, and the threshold current density can be further reduced.

Further, an n-type GaN semiconductor light guide layer 18 having a thickness of, for example, 0.01 to 0.3 μm is formed on the semiconductor carrier barrier layer 19 and forms a part of a core layer for guiding light. The n-type impurity density of the semiconductor optical guide layer 18 is, for example, 5 × 10 ¹⁶ to 2 × 10 ¹⁸ cm ⁻³ added to silicon. Even if silicon is not added intentionally, segregation from the semiconductor carrier barrier layer 19 causes An impurity may be added.

Further, a semiconductor active layer 17 made of, for example, InGaN having a thickness of 0.001 to 0.2 μm is formed on the semiconductor light guide layer 18. Semiconductor active layer 17
Is preferably thick enough to confine carriers in the stacking direction.
Is preferably 0.5 or less so that dislocation due to lattice mismatch with GaN is not introduced. Further, the semiconductor active layer 17 may have a multiple quantum well structure of, for example, InGaAlN and InGaN each having a thickness of 0.001 to 0.2 mm. It is desirable that the semiconductor active layer 17 not intentionally add impurities to promote recombination of holes and electrons and increase luminous efficiency.

Further, a p-type GaN semiconductor light guide layer 16 having a thickness of, for example, 0.01 to 0.3 μm is formed on the semiconductor active layer 17 and serves as a part of a core layer for guiding light. The p-type layer of this semiconductor light guide layer is, for example, Mg
Alternatively, Zn and Be are added impurities, for example, 5x10 ¹⁶ to 5x
10 ¹⁸ cm ^{-3 is} added. The semiconductor light guide layer 16 and the semiconductor light guide layer 18 have a larger band gap than the semiconductor active layer 17 and have a role of effectively confining electrons and holes in the semiconductor active layer 17.

Further, a p-type Al _x Ga ₁ -xN semiconductor carrier barrier layer 15 having a thickness of, for example, 0.1 to 1 μm is formed on the semiconductor light guide layer 16. The composition x of this Al is about 0.1 to 0.5. When x is increased, the refractive index is reduced and the band gap is increased, so that the semiconductor optical guide layer 16, the semiconductor active layer 17, and the semiconductor optical guide layer 18 have more light and electrons. Can be confined, but the crystallinity deteriorates and becomes porous, so that the resistance increases. Therefore, it is desirable that x is, for example, about 0.25. The p-type Al _x Ga ₁ -xN semiconductor carrier barrier layer 15 is formed by doping, for example, Mg, Zn, or Be from 1 × 10 ¹⁷ to 2 × 10 ¹⁸ cm ⁻³ . Further, the GaN semiconductor light guide layer 16
May be added to form Al _x Ga _{1-x y} In _y N.
May be set to 0 <y <0.5, typically about 0.05. By adding In in this way,
The lifetime of carriers in the semiconductor carrier barrier layer 15 can be lengthened, and the threshold current density can be further reduced.

Further, on the upper portion of the semiconductor carrier barrier layer 15 and the upper portion of the high resistance region 21, for example, Mg or Z
A p-type GaN semiconductor contact layer 14 having a thickness of 0.01 to 0.5 μm to which n and Be are added is formed. P of this part
The mold layer is doped with, for example, 1 × 10 ¹⁸ to 5 × 10 ¹⁸ cm ⁻³ using, for example, Mg, Zn, or Be as an additional impurity.

The high-resistance region 21 includes the semiconductor carrier barrier layer 15 outside the semiconductor active layer 17 and the semiconductor light guide layer 1.
6, a region in which the semiconductor active layer 17, the semiconductor light guide layer 18, and the semiconductor carrier barrier layer 19 are disordered and mixed. In the high resistance region 21, the semiconductor active layer 17, the semiconductor optical guide layer 16, and the semiconductor guide layer 18 are mixed with the semiconductor carrier barrier layers 15 and 19 having a lower dielectric constant. Therefore, the high-resistance region 21 has a lower dielectric constant than the semiconductor active layer 17, the semiconductor light guide layer 16, and the semiconductor light guide layer 18. Therefore, light can be more efficiently confined in the semiconductor active layer 17, the semiconductor light guide layer 16, and the semiconductor light guide layer 18 than in the high resistance region 21.

Further, since the semiconductor light guide layer 16 and the semiconductor light guide layer 18 are mixed with the semiconductor carrier barrier layer 15 and the semiconductor carrier barrier layer 19 each having a wider band gap, the high resistance region 21 The band gap is wider than the light guide layer 16 and the semiconductor light guide layer 18. Therefore, electrons and holes can be more efficiently injected into the semiconductor active layer 17, the semiconductor light guide layer 16, and the semiconductor light guide layer 18 sandwiched between the high resistance regions 21.

On the upper part of the semiconductor contact layer 14, a p-type electrode 8 made of, for example, Ni, Ti or Au to which Mg or Zn is added is formed. The p-type electrode 8 is an ohmic electrode for the semiconductor contact layer 14.

Further, on the n-type semiconductor layer 20 on which the semiconductor light emitting element 1 such as a semiconductor laser is formed, the semiconductor layer 2 is separated from the semiconductor carrier barrier layer 19 by 0.3 to 5 μm.
An electrode 9 serving as an n-type ohmic electrode for 0 is formed.

Further, the electrode 8 is a p-type electrode of the semiconductor light-emitting device 1, and the electrode 9 is an n-type electrode of the semiconductor light-emitting device 1. By applying a positive bias between these electrodes, the semiconductor light-emitting device 1 is sequentially turned on. In the semiconductor active layer 17
Then, recombination of electron holes is caused to emit light.

Next, the temperature sensor 2 of the semiconductor light emitting device of this embodiment will be described in detail using specific materials. This embodiment is characterized in that the n-type semiconductor layer 20 on which the n-type electrode 9 used in the semiconductor light emitting device 1 is formed.
There is a point on which electrodes 10, 11, 12 and a conductive film 13 are formed. Here, the conductive film 13 is an element whose resistance changes depending on the temperature.
It is formed of a semiconductor having a conductivity opposite to zero, for example, a p-type semiconductor made of GaN. This conductive film 1
When 3 is formed of a p-type semiconductor, for example, Mg, Zn, or Be is used as an additional impurity, and for example, 1 × 10 ¹⁶ to 5 × 10 ¹⁸
cm ^-3 has been added.

The electrodes 9, 10, 11, and 12 serve as electrodes of the conductive film 13 and have a thickness of, for example, 0.01 to 3 mm.
It is formed of a metal such as t, W, SiC, Ti, Au, Cr, Ni, Al and Ta, a laminated film thereof, an alloy thereof, or an oxide film thereof. These are, for example, a conductive film 13 formed in a linear shape.
The electrodes 9 and 12 are formed at both ends, respectively, to serve as first and second current terminals.

Here, the fact that the conductive film 13 is in a non-resistance contact with the semiconductor film 20, for example, a contact forming a Schottky barrier, indicates that the parasitic resistance of the semiconductor film 20 is reduced by the resistance of the conductive film 13. Is desirable.

Further, on the side of the conductive film 13 near the electrode 9, the conductive film 13 branches and the electrode 10, and on the side of the conductive film 13 near the electrode 12, the conductive film 13 branches. Thus, an electrode 11 is formed. These electrodes 10 and 11 serve as first and second voltage terminals. The electrodes 9, 10, 11, and 12 enable resistance measurement by the four-terminal method, and the resistance of the conductive film 13 can be measured regardless of the contact resistance of the electrodes.

Next, the manufacturing process of the semiconductor light emitting device of this embodiment will be described. First, as shown in FIG. 3, for example, alumina or a C-plane sapphire substrate, MgO, spinel, Si
A growth substrate 7 made of C is prepared. This growth substrate 7
In order to maintain the mechanical strength, it is desirable that the thickness be 50 μm or more.

Next, for example, metal organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), or vapor phase epitaxy
For example, GaN or AlN grown at a low temperature of 500 to 600 ° C using GaN or AlN as a buffer layer by the (VPE) method.
Then, while adding silicon, the thickness of 0.3 to 10 μm n
Type GaN semiconductor layer 20 is deposited on the entire surface. Before forming the n-type GaN semiconductor layer 20, the substrate may be patterned with, for example, SiO ₂ to reduce the dislocation density.

Next, for example, at 900 to 1100 ° C., while adding silicon, an n-type Al _x Ga _{1-x having} a thickness of 0.1 to 1 μm is added.
An N semiconductor carrier barrier layer 19 is deposited on the entire surface. here,
The semiconductor carrier barrier layer 19 is doped with In to add Al _x Ga _{1-x y}
In the case of In _y N, the growth temperature may be lowered to prevent re-evaporation of In, for example, the growth may be performed at 600 to 1000 ° C., typically 800 ° C.

Next, for example, at 800 to 1100 ° C., with a thickness of 0.
An n-type GaN semiconductor light guide layer 18 of 01 to 0.3 μm is entirely deposited. Next, for example, at a temperature of 600 to 1000 ° C and a thickness of 0.00
A semiconductor active layer 17 of, for example, InGaN of 1 to 0.2 μm is deposited on the entire surface. This semiconductor active layer 17 is made of, for example, InGaAlN and In each having a thickness of 0.001 to 0.2 μm.
It may have a multiple quantum well structure with GaN, for example, by changing the Al composition temporally and periodically during lamination.

Next, for example, at 900 to 1100 ° C., while adding Mg, Zn, or Be, the p-type GaN semiconductor light guide layer 1 is formed.
6 is deposited on the entire surface. Then, for example, at 900 to 1100 ° C,
A p-type Al _x Ga ₁ -xN semiconductor carrier barrier layer 15 is deposited over the entire surface while adding Mg, Zn, and Be. Here, the semiconductor carrier barrier layer 15 is doped with In to add Al _x Ga _{1-x y} In _y N
In that case, the growth temperature is lowered to prevent re-evaporation of In, for example, between 600 and 1000 ° C.
Typically, growth may be performed at 800 ° C.

Next, as shown in FIG. 4 (cross-sectional view) and FIG. 5 (top view), stripes are formed on both sides of an active region having a width of 1 to 100 μm by using, for example, lithography and selective diffusion or ion implantation. Zn is selectively added in the form, and thermal diffusion is performed at, for example, 300 to 1000 ° C. Thereby, the high resistance region 21 is formed. In this step, interdiffusion of atoms occurs, and the semiconductor carrier barrier layer 15, the semiconductor optical guide layer 16, the semiconductor active layer 17, the semiconductor optical guide layer 18, and the semiconductor carrier barrier layer 19 outside the semiconductor active layer 17 are disordered and mixed. Crystallize. As an alternative to diffusing Zn, for example, ion implantation of protons or argon may
1 may be formed. The depth of the high-resistance region 21 only needs to include the regions of the semiconductor light guide layer 16, the semiconductor active layer 17, and the semiconductor light guide layer 18, and it is not necessary to increase the resistance to the semiconductor carrier barrier layer 19.

Next, a p-type GaN semiconductor contact layer 14 is deposited over the entire surface at, for example, 800 to 1100 ° C. while adding Mg, Zn, or Be. Next, as shown in FIG. 6 (cross-sectional view) and FIG. 7 (top view), a portion other than the semiconductor light emitting element 1, that is, a high-resistance region 21 of an active region having a width of 1 to 100 μm is formed, for example, from 1 to 100 μm. Semiconductor layer 2 leaving 100 μm width
Lithography and etching are performed until the number reaches zero.

Next, as shown in FIG. 8 (cross-sectional view) and FIG. 9 (top view), for example, Pt, W, SiC, Ti, Au, A metal such as Cr, Ni, or Al is deposited on the semiconductor layer 20 by sputtering or evaporation,
Patterning is performed by lithography and etching. As an alternative to this manufacturing method, for example, a sacrificial film such as a resist is deposited on the entire surface in advance, lithography is performed, and a step reaching the semiconductor layer 20 is formed in the sacrificial film, and then the conductive thin film 13 is formed to a thickness of 0.01 to 3 μm. Of Pt, W, SiC, T
A so-called lift-off method of patterning the conductive thin film 13 by depositing a metal such as i, Au, Cr, Ni, Ta, or Al by sputtering or vapor deposition and removing the sacrificial film by etching may be used. After forming this metal film, for example, an oxide was formed at the metal grain boundaries of W, Ni, Cu, Cr, Ta, and Ti by performing treatment in an oxidizing atmosphere such as oxygen plasma or O ₂ gas. A compound film may be formed.

Next, a sacrificial film such as a resist is deposited on the entire surface in advance, and lithography is performed to form a step reaching the semiconductor contact layer 14 on the semiconductor contact layer 14, and then a sacrificial film having a thickness of 0.01 to 3 μm is formed. , Mg and Zn added
A p-type electrode 8 is formed by depositing a metal of Ni, Ti or Au by sputtering or vapor deposition and removing the sacrificial film by etching.

Next, a sacrificial film such as a resist is deposited on the entire surface in advance, and lithography is performed to form a step reaching the semiconductor layer 20 on the semiconductor layer 20.
An n-type electrode 9 is formed by depositing a metal of Ni, Ti or Au to which Si or Ge is added by sputtering or vapor deposition, and removing the sacrificial film by etching.

Finally, a sacrificial film such as a resist is deposited on the entire surface in advance, and lithography is performed to form a step reaching the semiconductor layer 20 on the semiconductor layer 20.
The electrodes 10, 11, and 12 of the temperature sensor are formed by depositing a metal of Ni, Ti or Au with a thickness of μm by sputtering or vapor deposition, and removing the sacrificial film by etching. Here, the parallel resistance between the electrodes 10, 11, 12 and the semiconductor film 20 may be larger than the sum of the resistance of the conductive thin film 13 and the resistance of the electrode 9 and the semiconductor film 20.

In order to form the electrodes 10, 11, and 12, the process of forming the electrode 8 and the formation of the electrode 1 by using a metal film are performed.
It may be performed simultaneously with the formation of 0, 11, and 12, and since a pn junction or a Schottky junction is formed between the electrodes 10, 11, and 12 and the semiconductor film 20, the resistance becomes high and the semiconductor film 20 is formed. This is desirable because the effect of parasitic resistance is reduced.

Further, the growth substrate 7 made of an insulator is polished from the back surface by polishing or etching, for example, to be thinned to a thickness of 50 to 100 μm. Further, diamond, silicon carbide, or diamond deposited or bonded on a heat sink 5 made of copper or aluminum, or ceramics such as alumina having high thermal conductivity.
The back surface of the growth substrate 7 is brought into contact with the submount 3 made of alumina, aluminum nitride film, mica, or silicon rubber, and the semiconductor light emitting device of the first embodiment shown in FIG. 1 (cross-sectional view) and FIG. It is formed.

Next, a control example for preventing thermal destruction of the semiconductor light emitting device 1 in this embodiment will be described. FIG. 10 is a control circuit for preventing the thermal destruction of the semiconductor light emitting device 1. The output of the current source 24 is connected to one electrode terminal 8 of the semiconductor light emitting element 1 composed of a diode or the like, and the other electrode terminal 9 is grounded and driven at a constant current. A control input node 23 is connected to the current source 24, and the output current changes according to the voltage or current of the control input node 23. Further, the control input node 23 is an output of the comparator 22. A resistor 13 made of a conductive thin film serving as a temperature sensor is connected to one of the current input terminals 1.
2 is connected to a second current source 25. The high voltage terminal 11 is connected to the negative control input of the comparator 22, and the low voltage terminal 10 is connected to the positive control input of the comparator 22. As the comparator 22, a comparator that changes linearly with the input may be used, or a comparator having a characteristic that the output voltage greatly changes with a certain voltage as a threshold may be used.

In the circuit configuration shown in FIG. 10, when the temperature of the semiconductor light emitting element 1 rises, the resistor 1 made of a conductive thin film
When 3 is formed of a metal thin film, its resistance increases. Therefore, the potential difference between the input terminal 11 and the terminal 10 of the comparator 22 increases. Therefore, the output 23 has a more negative voltage when the temperature is high, and suppresses the current output of the current source 24. By doing so, it is possible to apply a negative feedback to the semiconductor light emitting device 1, and it is possible to prevent the semiconductor light emitting device 1 from being broken or deteriorated when the temperature rises.

In FIG. 10, a semiconductor thin film can be used as the resistor 13 made of a conductive thin film. In this case, when the temperature increases, the resistance decreases because the carrier concentration increases. In this case, the comparator 2 in FIG.
If the positive input terminal 10 and the negative input terminal 11 are exchanged with each other, negative feedback can be applied in the same manner as described above.

The present embodiment has the following features. 1) Compared to the case where the semiconductor light emitting element and the temperature sensor are separately formed, the number of terminals can be reduced to five by using the terminals in common rather than the sum of two and four, and The probability of reliability problems due to bonding can be reduced, and misalignment and pad area can be reduced. 2) A planar resistance element can be used as the temperature sensor, and a four-terminal measurement pattern can be easily formed. Therefore, when measuring the resistance of the temperature sensor 2, the influence of the series parasitic resistance of the contact portion of the temperature sensor 2 can be removed, and the temperature can be measured more accurately. Further, when a metal thin film is used as the resistance element, it is possible to obtain a characteristic in which the resistance changes linearly with respect to the absolute temperature and the linearity of the resistance change is good. Therefore, when negative feedback is applied, linear operation can be performed more stably, and stable temperature management can be performed. 3) The temperature dependency of the threshold current I _th of the laser is, for example, that the temperature is T, and A and B are constants, and that from I _th to Bexp (AT), for example, SM Sze, "Physics of Semi
^{conductor Devices ", (2 nd edition} ) John Wiley and
Sons Inc. p732 (1981). Also, the laser light output Po is obtained by solving the injection currents I and C by solving the electron-hole recombination and the generation-annihilation differential equation for photons.
_Is dependent on Po to C (II _th ) as a constant. Therefore,
By precisely measuring the temperature as in this example,
By estimating I _th and thereby controlling II _{th to} be constant, the laser light output Po can also be constant. As a result, it is possible to omit the light receiving element for calibrating the laser light output, which is conventionally required, and it is possible to realize a laser light emitting element unit which can be more easily integrated and has a constant output. 4) In the manufacturing process of this embodiment, the formation of the electrode 9 of the temperature sensor 2 is shared with the formation of the electrode 9 of the semiconductor light emitting element 1. For this reason, the number of steps can be reduced as compared with the case where the temperature sensor 2 and the semiconductor light emitting element 1 are separately formed, and the manufacturing cost can be further reduced.

(Embodiment 2) FIG. 11 is a sectional view of a semiconductor light emitting device according to Embodiment 2 of the present invention, and FIG. 12 is a top view thereof. FIG. 11 is a sectional view taken along the line AA ′ of FIG.

In the first embodiment, the temperature sensor 2 is
However, in Example 2, the temperature sensor 2 was formed on the semiconductor layer 20 on the semiconductor layer 20.
This is an example in which the semiconductor light emitting device 1 is formed thereon.

That is, a p-type electrode 8 made of, for example, Ni, Ti or Au added with Mg or Zn is formed on the semiconductor contact layer 14. The p-type electrode 8 is an ohmic electrode for the semiconductor contact layer 14. The semiconductor contact layer 14, the semiconductor carrier barrier layer 15, the semiconductor light guide layer 16, the semiconductor active layer 17, the semiconductor light guide layer 18, and the semiconductor carrier barrier layer 19 form a pn junction and constitute a semiconductor light emitting device 1.

Further, an n-type electrode 9 having a conductivity type opposite to that of the p-type electrode 8 is formed at a distance of 0.3 μm from the semiconductor layer 19. The electrode 8 serves as a p-type electrode of the semiconductor light emitting device 1 and the electrode 9 serves as an n-type electrode of the semiconductor light emitting device 1. By applying a positive bias between them, the semiconductor laser light emitting device is biased in the forward direction. It can emit light.

Further, in this embodiment, the electrode 8 'and the conductive film 13 are formed on the p-type semiconductor contact layer 14 on which the p-type electrode 8 is formed. This makes it possible to more accurately measure the temperature of the semiconductor light emitting device. Here, the conductive film 13 is an element whose resistance changes with temperature, and has a thickness of, for example, 0.01 to 1 μm.
Of metal such as W, Ti, Au, Cr, Ni, Al and Ta.

The electrodes 8 and 8 ′ are formed on the conductive film 1.
3 electrodes, for example, Pt, having a thickness of 0.01 to 3 μm,
Metals such as W, SiC, Ti, Au, Cr, Ni, Al, Ta, or their laminated films or alloys, or even their oxide films are formed. For example, electrodes 8 and electrodes 8 'are formed at both ends of the conductive film 13 formed in a linear shape, respectively, and serve as first and second current / voltage terminals. Here, the fact that the conductive film 13 is in a non-resistance contact with the semiconductor contact layer 14, for example, a contact forming a Schottky barrier, separates the parasitic resistance of the semiconductor contact layer 14 from the resistance of the conductive film 13. It can be desirable.

The resistance of the conductor film 13 can be measured by the electrode 8 and the electrode 8 ′, and the temperature sensor 2 is formed by the electrode 8, the electrode 8 ′ and the conductive film 13.

The manufacturing steps of the present embodiment are the same as those of the first embodiment up to the steps corresponding to FIGS. After that, for example, a sacrificial film such as a resist is deposited on the entire surface in advance, and a step reaching the semiconductor layer 20 is formed on the semiconductor layer 20 by lithography to form a step reaching the semiconductor layer 20, and then a thickness of 0.01 to 3 μm is formed.
An electrode 9 of an n-type layer is formed by depositing a metal of Ni, Ti or Au to which Si or Ge is added by sputtering or vapor deposition and removing the sacrificial film by etching.

Next, for example, a sacrificial film such as a resist is deposited on the entire surface in advance, and lithography is performed to form a step reaching the semiconductor contact layer 14 on the semiconductor contact layer 14. A p-type electrode 8 is formed by depositing a μm metal of Ni, Ti or Au to which Mg or Zn has been added by sputtering or vapor deposition and etching away the sacrificial film.

After this step, in order to improve the resistance contact between the metal electrode 8 and the p-type semiconductor contact layer 14 or between the metal electrode 9 and the n-type semiconductor contact layer 20, a temperature of 300 to 1000.degree. Annealing may be inserted.

Further, for example, a sacrificial film such as a resist is deposited on the entire surface in advance, and a step reaching the semiconductor contact layer 14 is formed on the semiconductor contact layer 14 by lithography to form a step having a thickness of 0.01 to 3 μm. , Ni, Ti
Or by depositing Au metal by sputtering or vapor deposition, etching and removing the sacrificial film,
The electrode 8 'of the temperature sensor is formed. The step of forming the electrode 8 ′ may be performed, for example, in the step of forming a metal film for forming the electrode 9. A pn junction or a Schottky junction between the electrode 8 ′ and the semiconductor contact layer 14 may be formed. Since it is formed, the effect of the parasitic resistance through the semiconductor contact layer 14 is reduced, which is desirable.

Here, particularly, the resistance of the electrode 8 ′ to the p-type semiconductor contact layer 14 is larger than the sum of the resistance of the conductive thin film 13 and the resistance of the electrode 8 and the p-type semiconductor contact layer 14. When measuring the resistance of the conductive thin film 13, the influence of the parasitic resistance through the semiconductor contact layer 14 can be reduced.

Further, for example, the conductive thin film 13 becomes
A metal such as Pt, W, SiC, Ti, Au, Cr, Ni, Al, Ta or the like having a thickness of 0.01 to 3 μm is deposited on the semiconductor contact layer 14 by sputtering or vapor deposition, and patterned by lithography and etching. Do. As an alternative to this manufacturing method, for example, a sacrificial film such as a resist is deposited on the entire surface in advance,
After forming a step reaching the semiconductor film 20 by performing lithography, the conductive thin film 13 having a thickness of 0.01 to 3 μm is formed.
A so-called lift-off method of forming a conductive thin film 13 by depositing a metal such as Pt, W, SiC, Ti, Au, Cr, Ni, Al, Ta by sputtering or vapor deposition and etching away the sacrificial film. May be used.

After this metal film is formed, it is treated in an oxidizing atmosphere such as oxygen plasma or O ₂ gas to form an oxide on the metal grain boundaries of W, Ni, Cu, Cr, Ti and Ta. May be formed.

Further, for example, the growth substrate 7 is
The back surface may be polished by polishing or etching to reduce the thickness to 50 to 100 μm. Further, for example, diamond, silicon carbide, alumina, an aluminum nitride film, mica, or silicon rubber is deposited or bonded on a heat sink 5 made of ceramic such as copper or aluminum or alumina having a high thermal conductivity. By bringing the back surface of the growth substrate 7 into contact with the submount 3, the semiconductor light emitting device of the second embodiment is formed.

FIG. 13 is a control circuit diagram for preventing thermal destruction of the semiconductor light emitting device according to the second embodiment. One of the source and drain electrodes of the transistor Q1 is connected to the p-type electrode terminal 8 of the semiconductor light emitting element 1 composed of a diode or the like.
Here, the p-type electrode terminal 8 is also one of the electrodes of the temperature sensor 2. The other electrode 8 'of the temperature sensor 2 is connected to one of the source and drain electrodes of the transistor Q2. A region surrounded by a broken line corresponds to an integrated circuit of the semiconductor light emitting device 1 and the temperature sensor 2.

Further, the other source and drain electrodes of the transistor Q1 and the transistor Q2 are connected to each other and to the output of the current source 24. Also, a control input node 23 is connected to the current source 24,
The output current changes depending on the voltage or current of the control input node 23.

Further, for example, a bias voltage source 32 is connected to the control input of the transistor Q1, that is, the gate electrode. The bias voltage source 32 is set to be conductive so that an appropriate current for the laser to emit light flows between the drain and the source of Q1.

Further, the output of the first amplifier 29 is connected to the control input node 23, and the input of the first amplifier 29 is connected to a frequency filter, for example, a low-pass filter 27.
Output is connected. Here, as the first amplifier 29, an amplifier that changes linearly with the input may be used, or an amplifier having a characteristic that the output voltage greatly changes with a certain voltage as a threshold may be used. The cut-off frequency of the low-pass filter 27 is set to a frequency sufficiently lower than the frequency f of the signal source 28. For example, as the frequency f,
From 1M to 100Hz, cutoff frequency is 1/2 of f
It is desirable to do the following.

Further, the input of the low-pass filter 27 is connected to the output of the multiplier or mixer 30, and the first input of the multiplier or mixer 30 is connected to the second amplifier 3.
1 output. The input of the second amplifier 31 is connected to the electrode 8 ′, and the voltage of the electrode 8 ′ is amplified by the second amplifier 31. Here, it is assumed that the input impedance of the second amplifier 31 is sufficiently larger than the resistance between the electrode 8 ′ and the electrode 9. Voltage of electrode 8 'is V
_1, and the voltage of the second input of the mixer and V _2, the voltage of the output of the mixer and V _3.

Further, a second input of the multiplier or mixer 30 is connected to a signal source 28 having a voltage Vo, for example, of a frequency f through a capacitor 26, and furthermore, a control input of the transistor Q2, that is, a gate. Connected to input. A high-pass filter may be connected instead of the capacitor 26. Here, this signal source 28
So that the current flows between the drain and source of Q2,
It is desirable that the setting is made to be always in a conductive state. The current source 24 may be replaced with a voltage source if the impedance between the drain and the source of Q1 and Q2 is sufficiently large.

[0085] The semiconductor light emitting device of Example 2, the current I ₁ flowing from the electrode 8 to the semiconductor light emitting element 1, the sum of the current I ₂ flowing from the electrode 8 'to the semiconductor light emitting element 1 is determined by the current source 24 constant Therefore, the light emission intensity of the semiconductor light emitting device 1 becomes constant regardless of the voltage of the electrode 8 '.

In the semiconductor light emitting device of this embodiment, the transistor Q2, the signal source 28, the first amplifier 29, the multiplier or mixer 30, the low-pass filter 27, and the second amplifier 31 This is a device for measuring the impedance between the 'and the electrode 9 and applying the measured impedance to the node 23. In this semiconductor light emitting device, even if the output voltage of the component of the frequency f of the electrode 8 'is weak, the low-pass filter 27
Thus, the component of the frequency f can be separated and extracted from other frequency components. Therefore, the impedance between the electrode 8 'and the electrode 9, particularly the resistance component, can be measured with high sensitivity regardless of the DC voltage offset of the electrode 8' and the voltage offset of the amplifier 31.

FIG. 14 is an example of a signal waveform of the circuit shown in FIG. The symbols at the left end in FIG. 14 correspond to the symbols in FIG. It is assumed that the output V ₀ of the signal source 28 periodically changes between ₀ V and V _DD at a duty of 50%. Here, signal source 2
Although the rectangular waveform is shown as the output waveform 8, other shapes such as a sine wave and a triangular wave may be used. In response to the output of the signal source 28, the impedance between the drain of the transistor Q2 and the source is changed, the current I ₁ and the current I ₂ and the frequency f
, For example, the component of ΔI is superimposed. Here, the transistor Q1 and the transistor Q2 are connected to one current source 24.
Because it is supplied with current from the sum of the currents I ₁ and the current I ₂ is constant becomes a current supplied by the current source. Therefore,
Since the current flowing through the semiconductor light emitting element 1 is also constant, the light emission is constant without changing at the frequency f 2, which is desirable as a light emitting source.

[0088] Then, with the change of the current I _2, the voltage of the electrode 8 'is also changed in frequency f. At this time, the semiconductor light emitting element 1
Assuming that the sum of the resistance of the conductive film 13 and the resistance of the conductive film 13 is R, FIG.
As shown in, the V _1, the DC component of the maximum voltage V _a
The component of the frequency f of the amplitude of R ΔI is superimposed. here,
It is desirable that the resistance of the semiconductor light emitting element 1 is sufficiently lower than the resistance of the conductor film 13. In this case, the resistance of the conductor film 13 can be measured by measuring R.

Further, the voltage V ₂ at the second input of the multiplier or mixer 30 is adjusted to the frequency f so that the DC component becomes zero.
In this case, an AC having an amplitude ΔV having the same phase as the first input of the multiplier or mixer 30 is applied. The output V ₃ of the multiplier or mixer 30 includes -V _a ΔV / 2 and V _a ΔV / 2 -R ΔI
An amplitude of ΔV / 2 is obtained. Thus, the DC component of the output V ₃ of the multiplier or mixer 30 is -RΔI ΔV / 4. That is, the voltage V _{2 at} the second input of the multiplier or mixer 30
Of the voltage component of the multiplier or mixer 3 at the frequency f
A first input component whose phase is proportional to the uniform AC component of 0 is obtained as the DC component of V _3.

On the other hand, a component other than the frequency f amplified by the first amplifier 31, for example, a DC component, is converted into a component of the frequency f and is filtered by the low-pass filter 27. Therefore, for example, even if there is a DC offset component in the second amplifier 31, a component proportional to the resistance R of the electrode 8 'can be obtained very accurately as the output of the first amplifier 29. Here, by adjusting the amplification degree of the first amplifier 29 to positive or negative, negative feedback can be applied as in the first embodiment.

The semiconductor light emitting device of the second embodiment has the following features in addition to the features of the semiconductor light emitting device of the first embodiment. In the manufacturing process of the semiconductor light emitting device according to the second embodiment, the process of forming the conductive film 13 is after the process of forming the electrodes 8, 8 ', and 9. Therefore, the conductive film 13 can be formed without going through the annealing process for obtaining the low-resistance ohmic electrodes of the electrodes 8, 8 'and 9. Therefore, the number of heat steps required for the conductive film 13 can be reduced, and a more stable conductive film 13 can be formed.

In the semiconductor device of the second embodiment, the number of terminals of the integrated circuit of the temperature sensor 2 and the semiconductor light emitting device 1 can be reduced to three. Therefore, the number of wirings can be further reduced, wiring costs and occurrence of defects due to wirings can be reduced, and the pad area can be reduced.

(Embodiment 3) FIG. 15 is a cross-sectional view of a semiconductor light emitting device according to Embodiment 3 of the present invention, and FIG. 16 is a top view thereof. FIG. 15 is a sectional view taken along the line AA ′ of FIG.

The semiconductor light emitting device of the third embodiment is an example in which a p-type semiconductor, for example, a p-type GaN layer 14 processed into a linear shape is used as the conductor film 13 of the semiconductor light emitting device of the second embodiment.

That is, as shown in the figure, the linear p-type GaN layer 14 separated by the left-most mesa forms the conductive film 13.
And is formed on the high-resistance region 21. Further, p-type electrodes 8 and 8 ′ are formed at both ends of the conductive film 13. The electrode 8 'has a resistance to the p-type GaN layer 14.
It is a p-type electrode.

Since a semiconductor layer is used as the conductive film 13, the carrier density and the mobility change depending on the temperature, so that the temperature can be obtained from the specific resistance. The semiconductor light emitting device of the third embodiment has the following features in addition to the features of the semiconductor light emitting device of the second embodiment.

Since the conductive film 13 made of the p-type GaN layer is formed on the high-resistance region 21, the other p-type GaN layer 14
Can be electrically separated from the Also, the conductive film 1
Since the layer 3 is formed of a p-type GaN layer, it is not necessary to newly form a material other than the semiconductor light emitting element 1 as the conductive film 13, so that there is little problem of contamination and the number of steps is reduced. be able to.

(Embodiment 4) FIG. 17 is a sectional view of a semiconductor light emitting device according to Embodiment 4 of the present invention, and FIG. 18 is a top view thereof. FIG. 17 is a sectional view taken along the line AA ′ of FIG.

The semiconductor light emitting device of the fourth embodiment has the semiconductor layer 2
The n-type semiconductor layer of No. 0 is mesa processed and used as the conductive film 13 to form a temperature sensor. That is, as shown in the drawing, an electrode 9 ′ is formed on the n-type semiconductor layer 20 separately from the electrode 9, in addition to the electrode 9 being formed on the n-type semiconductor layer 20. At this time, the electrode 9 '
It is desirable to be an ohmic electrode for the n-type semiconductor layer 20.

Here, since the specific resistance of the semiconductor layer 20 changes with temperature, the semiconductor layer 20 in proportion to this specific resistance is changed.
By measuring the resistance of the electrode 9 ', the temperature can be measured.

FIG. 19 is a circuit diagram for measuring the temperature of the semiconductor light emitting device of Embodiment 4 and applying feedback. This circuit is basically the same as the circuit of FIG. 13, except that a conductive film 13 (resistance region) for measuring a temperature is formed on the n-type electrodes 9 and 9 ′ of the semiconductor light emitting device 1. . for that reason,
The direction of flowing the current from the constant current source 24 is reversed, and a voltage source 40 is connected to positively bias the pn junction of the semiconductor light emitting device 1. The circuit operation related to the measurement is basically the same as that of the second embodiment, and thus the description is omitted.

The semiconductor light emitting device of the fourth embodiment has the following features in addition to the features of the semiconductor light emitting device of the second embodiment. Since the conductive film 13 is formed of an n-type GaN layer, there is no need to newly form a material other than the semiconductor light emitting device 1 as the conductive film 13, thereby reducing the problem of contamination and reducing the number of steps. can do. Further, the semiconductor light emitting device 1
A plurality of electrodes for the n-type semiconductor are formed on both sides of the substrate, dispersing the current flowing through the electrodes, minimizing the influence of the resistance and contact resistance of the n-type semiconductor, and further suppressing the heat generated by the parasitic resistance components. be able to.

(Embodiment 5) FIG. 20 is a sectional view of a semiconductor light emitting device according to Embodiment 5 of the present invention, and FIG. 21 is a top view thereof.
FIG. 20 is a sectional view taken along the line AA ′ of FIG.

In the semiconductor light emitting device of the fifth embodiment, the temperature sensor 2 is formed not by a conductive thin film but by a pn junction. The temperature sensor 2 of the semiconductor light emitting device is composed of the semiconductor light emitting device 1
Semiconductor contact layer 14, semiconductor carrier barrier layer 1
5, the semiconductor light guide layer 16, the semiconductor active layer 17, the semiconductor light guide layer 18, and the semiconductor carrier barrier layer 19 are formed of the same film, and form a pn junction.

Further, as shown in FIG.
An ohmic electrode 9 for the n-type layer 20 is formed between the temperature sensor 2 and the layer 19 at a distance of 0.3 μm from the layer 19. The electrode 8 is a p-type electrode of the semiconductor light-emitting device 1, and the electrode 9 is an n-type electrode of the semiconductor light-emitting device 1. By applying a positive bias between them, the semiconductor light-emitting device 1 is biased in the forward direction. It can emit light.

Further, this semiconductor light emitting device is arranged such that the layers 14, 15, 16, 17,
The temperature sensor 2 is formed by laminating layers 18 and 19 and forming a p-type electrode 8 ″ on the top of the layers. Where this
It is desirable that a voltage equal to or lower than a voltage that gives a threshold current of the laser and a reverse bias equal to or lower than 0 V are applied to the pn junction.

When the reverse leak current I _leak between the electrode 8 ″ and the electrode 9 is determined by the recombination generation current and the diffusion current, the temperature is T, the Boltzmann coefficient is k, and n is between 1 and 2. V is the voltage applied to the junction and the junction, and is proportional to exp (V / nkT). Therefore, the temperature sensor 2 can measure the temperature T by measuring I _leak .

Here, the high-resistance region 21 is formed in the disordered mixed crystal region in the semiconductor light emitting element 1 to confine the current, but the mixed crystal region 21 is not formed in the temperature sensor 2 based on the pn junction.

In the present embodiment, unlike the first embodiment, a pn junction having good characteristics is formed in a region where the temperature sensor 2 is formed. Therefore, the high resistance layer 21 may not be formed in the temperature sensor 2 portion. desirable. However, if a pn junction having good characteristics can be formed, the high resistance region 21 composed of a mixed crystal region may be formed.

Here, the electrode 8 ″ serves as an electrode of the p-type semiconductor contact layer 14, and has a thickness of, for example, 0.01 to 3 μm.
It is formed of a metal such as Pt, W, SiC, Ti, Au, Cr, Ni, Al, or a laminated film or alloy thereof.

Next, a method for manufacturing the semiconductor light emitting device according to the fifth embodiment will be described with reference to FIGS. 22, 23, 24, 25, and 26. First, as shown in FIG. 22 (cross-sectional view), a laminated structure of the films 7 to 15 is formed as in the first embodiment.

Further, for example, by using lithography and selective diffusion or ion implantation, 1 to 100 μm
Zn is selectively added in stripes to both sides of the semiconductor active layer 17 having a width, and thermally diffused at, for example, 600 to 1000 ° C.
The layer outside the semiconductor active layer 17 is disordered and mixed to form a high-resistance region 21. As an alternative to diffusing Zn, for example, the high resistance region 21 may be formed by ion implantation of protons or argon. This high resistance region 21
The formation depth of the semiconductor light guide layer 16, the semiconductor active layer 17, and the active region of the semiconductor light guide layer 18 may be included in the formation depth.
It is not necessary to diffuse Zn.

Next, FIG. 23 (cross-sectional view) and FIG. 24 (top view)
For example, at 800 to 1100 ° C, Mg or Z
A p-type GaN layer 14 is deposited over the entire surface while adding n and Be. Next, for example, a portion other than the semiconductor light emitting element 1, that is, a high resistance region 21 on both sides of an active region having a width of 1 to 100 μm is left with a width of 1 to 100 μm, and
Lithography and etching are performed until the semiconductor film 20 is reached, so that the portion corresponding to the temperature sensor 2 also remains.

Next, FIG. 25 (cross-sectional view) and FIG. 26 (top view)
As shown in (1), after a sacrificial film such as a resist is entirely deposited in advance and lithography is performed, for example, a step reaching the semiconductor film 20 is formed in the sacrificial film,
Ni or Ti or Si or Ge doped with thickness of 0.01 to 3 μm
An n-type electrode 9 is formed by depositing Au metal by sputtering or vapor deposition and etching away the sacrificial film.

Next, a sacrificial film such as a resist is deposited on the entire surface in advance, and lithography is performed to form a semiconductor contact layer 1.
After a step reaching the semiconductor contact layer 14 is formed on the sacrificial film on the upper part of 4, a metal of Ni, Ti or Au added with Mg or Zn having a thickness of 0.01 to 3 μm is deposited by sputtering or evaporation, By removing the sacrificial film by etching, an electrode 8 and an electrode 8 'to be p-type electrodes are formed.

After this step, the metal electrode 8 and the p-type semiconductor contact layer 14, the metal electrode 8 'and the p-type semiconductor contact layer 14, or the metal electrode 9 and the n-type semiconductor layer 20 are formed.
300 to 10 for good ohmic contact with
You may insert annealing of 00 degreeC.

Next, the growth substrate 7 is polished from the back surface by polishing or etching, for example, to 50 to 100 μm.
To a thickness of Next, diamond or silicon carbide, alumina, aluminum nitride film, mica, or silicon rubber deposited or bonded on a heat sink 5 made of ceramics such as copper or aluminum or alumina having high thermal conductivity. The back surface of the growth substrate 7 is brought into contact with the mount 3 to form the semiconductor light emitting device of this embodiment.

The present embodiment has the following features in addition to the features of the first embodiment. Since one terminal of the semiconductor light emitting element 1 and one terminal of the temperature sensor 1 can be shared, the number of terminals can be reduced by one, so that the probability of reliability problems due to bonding is reduced, misalignment and pad area are reduced. Can be.

Further, since the pn junction layer structure of the semiconductor laser 1 is used as it is for the temperature sensor 2, the process for forming the temperature sensor 2 is not required again.
The temperature sensor 2 composed of a pn junction can be formed. Therefore, there is no increase in the number of steps as compared with the conventional steps.

The temperature dependence of the resistivity of the metal thin film is as follows:
While it changes almost in proportion to temperature, the recombination generation current and diffusion current of the pn junction change exponentially with temperature T in proportion to exp (V / nkT). Therefore, the sensitivity of the sensor to a higher temperature can be increased, and the controllability of the temperature at a higher temperature can be increased.

In the structure of this embodiment, the temperature sensor 2 and the semiconductor laser 1 can be formed with the same structure.
Therefore, if two parallel semiconductor laser structures are formed in advance, and one of the two structures having a better emission output characteristic is used as a semiconductor laser element and the other is used as a temperature sensor element, a semiconductor laser having a good characteristic and a temperature sensor can be obtained. Sensors can be obtained with high yield.

In the present structure, a method of biasing the pn junction in the forward direction can also be used. For example, when the forward current I flows up to the high level carrier injection condition,
I is proportional to the intrinsic semiconductor carrier density of the semiconductor forming the pn junction. Therefore, when the current is constant under the high level carrier injection condition, the forward voltage V
Varies as a linear function of temperature. Therefore, several mV / ° C
A sensor having the above sensitivity and good linearity with respect to temperature can be formed.

As the measuring circuit of the present embodiment, the electrodes 9 and 10 in FIG. 10 are read as the electrode 9, the electrodes 12 and 11 in FIG. 10 are read as the electrode 8 ″, and the conductive film 13 is used in the present embodiment. It can be replaced with the pn junction in the example.

The current I is modulated by the component of the frequency f,
By measuring the component of the frequency f 2 of the forward voltage formed at the pn junction, the effect of the DC offset component of the measurement circuit can be reduced, and more accurate measurement can be performed.

(Embodiment 6) FIGS. 27, 29 and 30 are sectional views of a semiconductor light emitting device according to Embodiment 6 of the present invention, and FIG. 28 is a top view thereof. FIG. 27 is a sectional view taken along the line AA ′ of FIG. 28,
FIG. 29 is a sectional view taken along the line BB ′ of FIG. 28, and FIG.
5 shows a cross-sectional view taken along the line CC ′ of FIG.

This embodiment is characterized in that a plurality of diodes serving as the temperature sensor 2 are formed. FIG.
As shown at 28, the region on the left is the semiconductor contact layer 14, the semiconductor carrier barrier layer 15, the semiconductor light guide layer 1
6. The semiconductor light emitting device 1 is constituted by a pn junction including a semiconductor active layer 17, a semiconductor light guide layer 18, and a semiconductor carrier barrier layer 19. This structure is similar to each of the embodiments described above.

As shown in FIG. 27 and FIG. 28, the semiconductor carrier barrier layer 19 is
An ohmic electrode 9 for the n-type semiconductor layer 20 is formed at a distance of m. The electrode 8 is a p-type electrode of the semiconductor light-emitting element 1 and the electrode 9 is an n-type electrode of the semiconductor light-emitting element 1. By applying a positive bias between these electrodes, the semiconductor light-emitting element is forward biased to emit light. Can be done.

Also, as shown in FIGS. 27, 28, 29, and 30, the electrode 9 applied 0.3 to 5 μm to the right region.
The temperature sensor 2 having the same laminated structure as the semiconductor contact layer 14, the semiconductor carrier barrier layer 15, the semiconductor light guide layer 16, the semiconductor active layer 17, the semiconductor light guide layer 18, and the semiconductor carrier barrier layer 19 at a distance of m One is formed. In the figure, an example in which two temperature sensors 2 are formed is shown, but three or more temperature sensors may be formed. This temperature sensor 2
Are formed on the same semiconductor layer 20 as the semiconductor laser 1 and have the same laminated structure. Further, a p-type electrode 8 ″ and a p-type electrode 8 ″ ′ are formed thereon.

It is desirable that a voltage equal to or lower than the voltage for providing the threshold current of the laser or a reverse bias equal to or lower than 0 V is applied to the pn junction of the temperature sensor 2. When the current I _junc between the electrode 8 ″ and the electrode 9 is determined by the recombination generation current and the diffusion current, the temperature is T, the Boltzmann coefficient is k, n
Is a number between 1 and 2, and V is the voltage applied to the junction, and is proportional to exp (V / nkT). Therefore, the temperature T can be measured by measuring I _junc . Since the plurality of temperature sensors 2 are formed in the same shape, a plurality of pn junctions having uniform characteristics can be obtained, and the shape effect, the recombination lifetime of minority carriers, and the temperature dependence of the band gap can be obtained. The temperature can be accurately measured regardless of the temperature.

Hereinafter, this will be described. Here, a forward voltage V _F1 is applied between the electrode 8 ″ and the electrode 9, and the current flowing at that time is defined as I _F1 . On the other hand, the forward voltage V _F2 and electrode 8 '''between the electrodes 9 is引加, the current flowing at that time and I _F2. Considering the case where it is determined by the recombination generation current and diffusion current, in a diode with the same junction area with uniform characteristics,
The following equation holds.

I _F1 = A ₁ * exp (V _F1 / nkT) I _F2 = A ₁ * exp (V _F2 / nkT) Equation (1) In equation (1), A ₁ is equal to V _F1 and V _F2 . This coefficient does not depend on temperature T, minority carrier lifetime, and pn junction area. In addition, the constant n in equation (1) is 1 under the condition of the diffusion current.
The constant is 2 under the recombination current and high injection conditions, and does not depend on the temperature T, minority carrier lifetime, or pn junction area.

[0132] from equation (1), and can delete the A _1, the temperature T is determined by the following formula. T = q / nk * (V _F1 −V _F2 ) / {ln (I _F1 / I _F2 )} Equation (2) Equation (2) does not include terms that depend on the shape effect or minority carrier lifetime. Therefore, the temperature can be determined without being affected by the shape effect as compared with the second embodiment. Further, the temperature T 1 can be obtained not by the absolute values of I _F1 and I _F2 but by their ratio.

The manufacturing steps of this embodiment are the same as those of the fifth embodiment and will not be described. Here, a manufacturing process diagram corresponding to FIG. 24 of the fifth embodiment is shown in FIG. As shown in FIG. 31, the high-resistance region 21 indicates a disordered region formed by, for example, diffusing Zn or injecting protons, and the semiconductor carrier barrier layer 15 indicates a surface of an active region which is not disordered. ing. In addition, a dotted line indicates a boundary of a mesa region reaching the semiconductor layer 20 to be formed later.

Forming a pattern so that the shapes of the plurality of regions 15 of the temperature sensor 2 in the right region are equal;
Also, it is important to form a pattern so that the boundary of the mesa region reaching the semiconductor layer 20 to be formed later has the same shape by a plurality of pn junctions included in the temperature sensor 2.

It is desirable that the position of the electrode 8 ″ with respect to the electrode 9 and the position of the electrode 8 ″ ′ with respect to the electrode 9 be symmetrical. FIG. 32 is a control circuit diagram for preventing thermal destruction of the semiconductor light emitting device of this embodiment.

In FIG. 32, the portion surrounded by the dotted line is the semiconductor light emitting element portion shown in FIG. 27 and the like. Semiconductor light emitting device 1
The output of the current source 24 is connected to the p-type electrode terminal 8. A control input node 23 is connected to the current source 24, and the output current changes according to the voltage or current of the control input node 23.

Reference numerals 37 and 38 denote the temperature sensor 2, and one ends of the temperature sensor diodes 37 and 38 are commonly connected to the electrode 9 and are grounded. The electrode 8 ″ of the temperature sensor diode 37 is connected to an independent current source of a so-called current mirror constant current source circuit, and the electrode 8 ′ ″ of the temperature sensor diode 38 is connected to the subordinate current of the current mirror constant current source circuit. Connected to the source.

Q3, Q4, Q4 'are transistors having uniform characteristics, and a current equal to the current flowing from the drain electrode of Q3 flows from the drain electrodes of Q4 and Q4'. Like Q4 ', multiple transistors with the same characteristics as Q3 may be connected in parallel with Q4, or Q4
In the configuration without 4 ', the channel width of Q4 is changed and Q4 and Q3
May be changed.

In the following description, for the sake of simplicity, an operation in a case where two transistors Q4 and Q4 'are connected in parallel as shown in FIG. 32 will be described. Here, it is assumed that the input impedance of the comparator 22 is sufficiently larger than the resistances of the resistor 34 and the temperature sensor diode 38. In this condition, the current I _F1 flowing through the temperature sensor diodes 37 has a two-fold current I _F2 flowing through the temperature sensor diodes 38.

Therefore, assuming that the voltage of the electrode 8 ″ is V _F1 and the voltage of the electrode 8 ″ ′ is V _F2 , from the equation (2), the temperature T becomes
T = q / nk * (V _F1 −V _F2 ) / {ln2}. Therefore, as shown in FIG. 32, by connecting the positive input 36 of the differential amplifier 22 to the electrode 8 ″ and the negative input 35 to the electrode 8 ″ ′, the output proportional to the temperature T can be changed to the output of the differential amplifier 22. Can be obtained as

Further, as shown in FIG.
For example, an input of a circuit 33 serving as a voltage limiter is connected to the output of the second circuit. The output of this voltage limiter is
It is connected to a control input of a current source 24 for driving the semiconductor light emitting device 1. With such a configuration, the current flowing through the semiconductor light emitting device 1 can be limited at a certain temperature or higher, and a protection circuit against thermal destruction and deterioration of the semiconductor light emitting device can be realized.

Further, by forming a circuit exponentially dependent on the input voltage as the voltage limiting circuit 33 and configuring the current source 24 so as to apply an offset current proportional to the value of the control input 23, the temperature T can be reduced. When the semiconductor light emitting element 1 performs the laser operation even if it changes, it is possible to realize a circuit that keeps the light emission intensity almost constant.

In this embodiment, the first embodiment and the second embodiment are used.
In addition to the features described above, there are the following features. First, by using two terminals in common, the number of terminals can be reduced to four, so that the probability of reliability problems due to bonding can be reduced, and misalignment and pad area can be reduced.

Further, by adopting a structure in which a plurality of temperature sensors are integrated and formed in the same shape, a plurality of pn junctions having uniform characteristics can be obtained, and the shape effect and the recombination lifetime of minority carriers can be obtained. The temperature can be accurately measured irrespective of the temperature dependency of the band gap, and the absolute accuracy of the power supply for driving the temperature sensor.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. In the semiconductor light emitting device according to the present invention, the thickness of the growth substrate 7 of the semiconductor light emitting device 1 is large, and the thermal resistance from the front surface to the back surface of the growth substrate 7 is larger than the thermal resistance from the semiconductor light emitting device 1 to the growth substrate 7. In that case, it exerts its effect.

In each of the above embodiments, the growth substrate 7
The insulator having a lower thermal conductivity than the semiconductor layer 20 has been described as an example. However, the growth substrate 7 does not necessarily need to be an insulator, and may be, for example, SiC.
If the quotient obtained by dividing the thermal conductivity of the semiconductor substrate 20 by the film thickness of the growth substrate 7 is smaller than the quotient obtained by dividing the thermal conductivity of the semiconductor layer 20 by the distance of the interface from the semiconductor active layer 17 to the growth substrate 7, the effect is exhibited. I do.

In each of the above embodiments, a semiconductor laser element is shown as the semiconductor light emitting element 1. However, for example, an LED element may be used instead of a laser element, and the structure of the present embodiment can measure the temperature more accurately. Is clear. In this case, as the LED, for example, a structure in which the Al _x Ga _{1- xy} In _y N of the semiconductor carrier barrier layers 19 and 15 and the GaN layer of the semiconductor light guide layers 18 and 16 are omitted may be used.

In each of the embodiments, the GaN-based semiconductor light emitting device 1 has been described.
It is clear that a similar problem occurs in a semiconductor laser formed on a substrate having a lower thermal conductivity than ZnSe or ZnS, and it is similarly effective if GaN is replaced with a ZnSe-based material.

Further, the temperature sensor using the diffusion current and the recombination current of the pn junction has been described. For example, when the base and the collector are short-circuited by a bipolar transistor and the collector current is kept constant, the voltage between the base and the emitter is reduced. In the measurement method, the same principle can be used as a temperature sensor.

Also, two transistors having the same characteristics are operated with different collector currents, and the voltage between the base and the emitter of the two transistors is measured. The voltage variation between them may be reduced.

Further, the current mirror circuit may be formed by other realization methods, for example, Q3, Q4, Q4 '' may be formed by an n-type MISFET. Further, a current flowing through a Schottky junction diode may be used as the temperature sensor.

Although the example in which the p-type semiconductor is formed on the n-type semiconductor has been described, the n-type semiconductor may be formed on the p-type semiconductor. Although the temperature sensor 2 using the pn junction is shown, this position should be formed at a position where light emitted from the semiconductor light emitting element 1 is difficult to enter to prevent an increase in leak current due to light incident on the pn junction. desirable. Therefore, for example, when the semiconductor light emitting element 1 is a laser element, it is preferable to form a temperature sensor as shown in FIG. 31 along the width direction in which the high-resistance region 21 is formed and light is confined. desirable.

As the method of forming the insulating film, an oxide film formed by thermal oxidation, an oxide film implanted with oxygen at a low acceleration energy of about 30 keV, or a method of depositing an insulating film may be used. Or a method of depositing a silicon nitride film, or a combination thereof.

The method of forming the element isolation film and the insulating film itself is as follows.
Other methods for converting a metal film into an insulating film, such as a method of injecting oxygen ions into a deposited metal film or a semiconductor film, or a method of oxidizing or nitriding the deposited semiconductor film may be used.

In addition, if the temperature sensor is formed at a position where the thermal resistance from the semiconductor light emitting element 1 is lower than the interface between the submount 3 and the growth substrate 7 immediately below the semiconductor light emitting element 1, the present embodiment is used. The effect of the example appears. FIG. 33 is, for example, a cross section corresponding to the first embodiment of FIG. 1 and shows the distance between the respective structures.

In FIG. 33, x is a distance along the semiconductor film 20 and the growth substrate 7 from the emission center of the semiconductor light emitting element 1 to the center of the conductive film 13 serving as a temperature sensor. Further, y is the width of the semiconductor light emitting element 1 in the direction in which x is measured, d ₁ is the thickness of the semiconductor film 20 at the portion where the conductive film 13 is formed, and d ₂ is the thickness of the growth substrate 7. It is a film thickness.

In this case, the thermal conductivity of the semiconductor film 20 is set to H
_20. Assuming that the thermal conductivity of the growth substrate 7 is H ₇ , by satisfying the following condition, the thermal resistance from the semiconductor light emitting element 1 is higher than the interface between the submount 3 directly below the semiconductor light emitting element 1 and the growth substrate 7. Can be reduced, and the effects of the invention described below occur.

H ₂₀ * d ₁ / x> H ₇ * y / d ₂ Equation (3) That is, x should be x <H ₂₀ * d ₁ * d ₂ / (H ₇ * y). For example, a sapphire substrate (H
₇ = 60 Wm ^-1 K ^-1 ), and GaN (H ₂₀ = 1
30Wm ^-1 K ^-1 ), 0.3 μm or more for d _{1 and} 50 for d ₂
μm or more, semiconductor laser etching stripe width y
Assuming that the thickness is 20 μm, the above condition can be satisfied when x is 1.6 μm or less.

FIG. 34 is a cross section corresponding to the semiconductor light emitting device of FIG. 11, showing the distance between the structures. In FIG. 34, x denotes the semiconductor film 2 from the emission center of the semiconductor light emitting element 1 to the center of the conductive film 13 serving as a temperature sensor.
0 Distance along the stacking direction. Z is the semiconductor film 2 from the emission center of the semiconductor light emitting element 1 to the growth substrate 7.
The distance along the zero stacking direction, d _2, is the film thickness of the growth substrate 7.

In this case, the thermal conductivity of the semiconductor film 20 is H
_20. Assuming that the thermal conductivity of the growth substrate 7 is H ₇ , by satisfying the following conditions, the thermal resistance from the semiconductor light emitting element 1 is higher than the interface between the submount 3 immediately below the semiconductor light emitting element 1 and the growth substrate 7. Can be reduced, and the effects of the invention described below occur.

1 / (H ₂₀ / x) <1 / (H ₂₀ / z) + 1 / (H ₇ / d ₂ ) Equation (4) That is, for x, x <z + d ₂ * H ₂₀ / You may be familiar with the H _7. Usually, the semiconductor film 20 formed on the growth substrate 7
In order to improve the crystallinity of the semiconductor film 20 and to prevent impurity diffusion from the growth substrate 7,
It is formed thick. Therefore, the condition of z> x can be easily realized. When z> x, the distance from the semiconductor light emitting element 1 to the conductive film 13 is higher than the interface between the submount 3 and the growth substrate 7 immediately below the semiconductor light emitting element 1 irrespective of the thermal conductivity of the growth substrate 7. Thermal resistance can be reduced. Therefore, even when a material having better thermal conductivity than the semiconductor layer 20, such as SiC, is used for the growth substrate 7, the temperature can be measured more accurately than in the conventional example.

Further, when the temperature sensing region is the semiconductor layer 20 immediately below the semiconductor light emitting device, the temperature of the semiconductor layer 20 is lower than the interface between the submount 3 and the growth substrate 7 immediately below the semiconductor light emitting device 1. The thermal resistance of the temperature sensing region can be reduced, and the effects of the invention described below occur.

FIG. 35 is a cross section corresponding to the semiconductor light emitting device of FIG. 20, showing the distance between the structures. FIG.
In FIG. 5, x is a distance along the semiconductor film 20 and the growth substrate 7 from the emission center of the semiconductor light emitting element 1 to the center of the pn junction serving as a temperature sensor. Also, y is the semiconductor light emitting element 1
Is the width in the direction in which x is measured, and y ₂ is the temperature sensor 2
Is the width of the pn junction in the direction in which x is measured. the s et, d ₁ is the thickness of the semiconductor film 20 in a portion forming the conductive film 13, d ₂ is the thickness of the growth substrate 7. Further, z ₂ is calculated from the pn junction serving as the temperature sensor 2 to the growth substrate 7.
Up to the distance along the stacking direction of the semiconductor films 20.

In this case, the thermal conductivity of the semiconductor film 20 is H
_20. Assuming that the thermal conductivity of the growth substrate 7 is H ₇ , by satisfying the following conditions, the thermal resistance from the semiconductor light emitting element 1 is higher than the interface between the submount 3 immediately below the semiconductor light emitting element 1 and the growth substrate 7. Can be reduced, and the effects of the invention described below occur.

1 / (H ₇ * y / d ₂ )> 1 / (H ₂₀ * d ₁ / x) + 1 / (H ₂₀ * y ₂ / z ₂ ) Formula (5) In a semiconductor light emitting device formed by vapor phase growth or liquid phase growth on an insulator substrate, even if the thermal resistance of the insulator is larger than the thermal resistance of the thin film semiconductor light emitting layer, the temperature of the region other than the heat sink changes. However, the temperature can be measured more accurately. Therefore, when estimating the temperature of the thin film semiconductor light emitting layer from the output of the temperature sensor, the error is reduced.

Further, in the semiconductor light emitting device according to the present invention, since the temperature sensor is formed on the semiconductor light emitting device, no misalignment occurs between the temperature sensor and the semiconductor light emitting device when they are formed on the heat sink. . For this reason,
The distance from the thin-film semiconductor light-emitting layer to the temperature sensor does not vary from element to element, and the change in distance due to expansion due to temperature change is small. Therefore, the fluctuation of the thermal resistance between the thin-film semiconductor light emitting layer and the temperature sensor is small. For this reason, the temperature difference between the temperature sensor and the thin-film semiconductor light-emitting layer is less likely to fluctuate, and the difference between the temperature of the temperature sensor and the temperature of the thin-film semiconductor light-emitting layer can be easily kept constant.

Further, since the semiconductor light emitting device according to the present invention is formed on the temperature sensor and the semiconductor light emitting device, it is easy to improve the degree of integration thereof. Further, in the semiconductor light emitting device according to the present invention, since the temperature sensor is formed of the same material as the semiconductor light emitting device, the thermal expansion coefficient of the temperature sensor is equal to that of the semiconductor light emitting device.
Therefore, the possibility that peeling or cracks are formed between the temperature sensor and the substrate is reduced.

In the semiconductor light emitting device according to the present invention, the temperature dependence of the thermal conductivity of the substrate of the temperature sensor is equal to the temperature dependence of the thermal conductivity of the substrate of the semiconductor light emitting device. The thermal resistance can be made more constant and smaller, the difference between the temperature of the temperature sensor and the temperature of the semiconductor thin film layer can be easily kept constant, and the response speed can be improved. Therefore, it is possible to form a protection circuit capable of responding to a sudden temperature rise sufficiently quickly.

In the semiconductor light emitting device according to the present invention, when the temperature sensor is formed on an insulating substrate having a high thermal resistance, the temperature sensor and the semiconductor light emitting device can be used even if the heat resistance of the heat sink is small. Is smaller, and the temperature can be more accurately measured by the temperature sensor.

In the semiconductor device according to the present invention, the difference between the temperature of the temperature sensor and the temperature of the thin-film semiconductor light emitting layer can be kept constant. Thus, thermal destruction and deterioration of the light emitting element can be prevented.

Further, in the semiconductor light emitting device according to the present invention, the number of submounts for connecting the heat sink and the light emitting device can be reduced from two required for the conventional light emitting device and one required for the sensor. The number of elements can be reduced and high integration can be achieved.

In the semiconductor light emitting device according to the present invention, since the accuracy of measuring the temperature is improved, the information of the temperature sensor is fed back to the injection current value of the light emitting device without correcting the light intensity by the light receiving device. Various effects such as stable light output can be expected.

[0173]

As described in detail above, the semiconductor light emitting device of the present invention keeps the temperature difference between the device for measuring temperature and the semiconductor light emitting device constant, and keeps the thermal stress between them small. In addition, there is an effect that it can be formed with a high degree of integration.

[Brief description of the drawings]

FIG. 1 is a sectional view of a semiconductor light emitting device according to a first embodiment of the present invention.

FIG. 2 is a top view of the semiconductor light emitting device according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating a manufacturing step of the semiconductor light emitting device according to the first embodiment of the present invention.

FIG. 4 is a sectional view in a manufacturing process of the semiconductor light emitting device according to the first embodiment of the present invention.

FIG. 5 is a top view in a manufacturing step of the semiconductor light-emitting device according to the first embodiment of the present invention.

FIG. 6 is a cross-sectional view illustrating a manufacturing step of the semiconductor light emitting device according to the first embodiment of the present invention.

FIG. 7 is a top view in the manufacturing process of the semiconductor light emitting device according to the first embodiment of the present invention.

FIG. 8 is a cross-sectional view illustrating a manufacturing step of the semiconductor light-emitting device according to the first embodiment of the present invention.

FIG. 9 is a top view in a manufacturing step of the semiconductor light-emitting device according to the first embodiment of the present invention.

FIG. 10 is a circuit diagram of the semiconductor light emitting device according to the first embodiment of the present invention.

FIG. 11 is a sectional view of a semiconductor light emitting device according to a second embodiment of the present invention.

FIG. 12 is a top view of a semiconductor light emitting device according to a second embodiment of the present invention.

FIG. 13 is a circuit diagram of a semiconductor light emitting device according to a second embodiment of the present invention.

FIG. 14 is a circuit timing chart of the semiconductor light emitting device according to the second embodiment of the present invention.

FIG. 15 is a sectional view of a semiconductor light emitting device according to a third embodiment of the present invention.

FIG. 16 is a top view of a semiconductor light emitting device according to a third embodiment of the present invention.

FIG. 17 is a sectional view of a semiconductor light emitting device according to a fourth embodiment of the present invention.

FIG. 18 is a top view of a semiconductor light emitting device according to a fourth embodiment of the present invention.

FIG. 19 is a circuit diagram of a semiconductor light emitting device according to a fourth embodiment of the present invention.

FIG. 20 is a sectional view of a semiconductor light emitting device according to a fifth embodiment of the present invention.

FIG. 21 is a top view of a semiconductor light emitting device according to a fifth embodiment of the present invention.

FIG. 22 is a sectional view in a manufacturing step of the semiconductor light-emitting device according to the fifth embodiment of the present invention.

FIG. 23 is a sectional view in a manufacturing step of the semiconductor light-emitting device according to the fifth embodiment of the present invention.

FIG. 24 is a top view in a manufacturing step of the semiconductor light-emitting device according to the fifth embodiment of the present invention.

FIG. 25 is a cross-sectional view illustrating a manufacturing step of the semiconductor light-emitting device according to the fifth embodiment of the present invention.

FIG. 26 is a top view illustrating a manufacturing step of the semiconductor light emitting device according to the fifth embodiment of the present invention.

FIG. 27 is a sectional view of a semiconductor light emitting device according to a sixth embodiment of the present invention.

FIG. 28 is a top view of a semiconductor light emitting device according to a sixth embodiment of the present invention.

FIG. 29 is a sectional view of a semiconductor light emitting device according to a sixth embodiment of the present invention.

FIG. 30 is a sectional view of a semiconductor light emitting device according to a sixth embodiment of the present invention.

FIG. 31 is a top view in a manufacturing step of the semiconductor light-emitting device according to the sixth embodiment of the present invention.

FIG. 32 is a circuit diagram of a semiconductor light emitting device according to a sixth embodiment of the present invention.

FIG. 33 is a sectional view of the semiconductor light emitting device according to the first embodiment of the present invention.

FIG. 34 is a sectional view of a semiconductor light emitting device according to a second embodiment of the present invention.

FIG. 35 is a sectional view of a semiconductor light emitting device according to a sixth embodiment of the present invention.

FIG. 36 is a cross-sectional view of a conventional semiconductor light emitting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Semiconductor light emitting element 2 ... Temperature sensor 3 ... Submount 4 ... Submount 5 ... Heat sink 6 ... Thin film semiconductor light emitting layer 7 ... Growth substrate 8 ... 1st conductivity type electrode 9 ... 2nd conductivity type electrode 10 ... 2nd conductivity Type electrode 11: Second conductivity type electrode 12: Second conductivity type electrode 13: Conductive thin film 14: First conductivity type semiconductor contact layer 15: First conductivity type semiconductor carrier barrier layer 16: First conductivity type semiconductor light guide layer Reference Signs List 17 semiconductor active layer 18 second conductivity type semiconductor light guide layer 19 second conductivity type semiconductor carrier barrier layer 20 second conductivity type semiconductor layer 21 high resistance region 22 differential amplifier 23 output 24 current source 25 ... Current source 26 ... Capacitor 27 ... Low-pass filter 28 ... Current source 29 ... Amplifier 30 ... Mixer 31 ... Amplifier 32 ... Bias voltage source 33 ... Voltage limiter 34 ... Resistance 35 ... Negative input Force 36 ... Positive input 37 ... Temperature sensor diode 38 ... Temperature sensor diode 40 ... Voltage source

Claims (8)

[Claims] 1. A semiconductor device comprising: a substrate; a semiconductor layer formed on the substrate; a semiconductor light emitting device formed on the semiconductor layer; and a temperature sensor formed on the semiconductor layer. Semiconductor light emitting device. 2. The semiconductor light emitting device according to claim 1, wherein said temperature sensor is an impedance element whose resistance changes with temperature. 3. The semiconductor light emitting device according to claim 1, wherein said substrate is an insulator. 4. The semiconductor light emitting device according to claim 3, wherein said insulator substrate has a lower thermal conductivity than said semiconductor layer. 5. The insulator substrate includes an aluminum oxide film,
The semiconductor light emitting device according to claim 3, wherein the semiconductor includes gallium nitrogen or ZnSe. 6. The semiconductor device according to claim 1, wherein said semiconductor contains gallium nitrogen or ZnSe, and said semiconductor layer is formed on said substrate via silicon carbide. The semiconductor light emitting device according to claim 3 or 4. 7. A quotient obtained by dividing the thermal conductivity of the silicon carbide by its film thickness is smaller than a quotient obtained by dividing the thermal conductivity of the semiconductor layer by a distance of an interface from the semiconductor light emitting portion to the silicon carbide. 7. The semiconductor light emitting device according to claim 6, wherein: 8. A first semiconductor layer of a first conductivity type formed on an insulator substrate, and a second semiconductor layer of a second conductivity type different from the first conductivity type formed on the first semiconductor layer. A semiconductor layer; a semiconductor light emitting device formed from the first semiconductor layer and the second semiconductor layer; a first electrode formed on the second semiconductor layer; A semiconductor light emitting device comprising second and third electrodes formed, wherein a resistance between the second electrode and the third electrode changes with temperature.