JP3260001B2 - Semiconductor element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device using a semiconductor layer containing carbon as a constituent element.

[0002]

2. Description of the Related Art Group IV semiconductors containing carbon as one of the constituent elements, especially silicon carbide (SiC), have a wide bandgap of 2.2 to 3.2 eV and are applicable to visible LEDs, high voltage and high speed switching elements. Expected. Particularly in the field of visible LED, a pn junction type LED capable of emitting blue light is being developed for practical use.

Since the band structure of SiC is an indirect transition type, light emission must be accompanied by absorption and emission of phonons. For this reason, the inter-band emission transition probability is very low, and a conventional method of using a transition between a donor (D) and an acceptor (A) has been adopted for use as an LED. However, such an element is characterized in that the wavelength of emitted light varies depending on the difference in the distance between the lattice positions occupied by D and A. That is, the LED has a drawback that the color tone is deteriorated because light emission is spread over a wide wavelength range. Also, DA pair emission has a problem that the emission peak wavelength varies depending on the magnitude of the current flowing through the LED, and the color changes depending on the magnitude of the current. This leads to deterioration of the display characteristics of the full-color LED display element, which is a serious problem.

Further, since SiC has a wide bandgap, the level of impurities determining the conductivity type is deep. For example, N in SiC is
It is close to 100meV. Therefore, when N is doped as a donor impurity, the carrier activation rate is low with respect to the impurity concentration, and only about 10% is activated. Therefore, in order to grow an n-layer crystal with a high carrier concentration, the concentration of the impurity to be doped needs to be at least one digit higher than the carrier concentration. Further, the activation energy of Al as an acceptor impurity is as high as 200 meV in SiC, so that the activation rate is only about 1%. Therefore, in order to grow a crystal having a high carrier concentration in the p-layer, the concentration of the impurity to be doped needs to be higher than the carrier concentration by two digits or more. For this reason,
If an attempt is made to obtain an n-layer or p-layer crystal having a high carrier concentration, extra defects are generated, and these defects cause the electrical and optical properties to be extremely deteriorated. As a doping method for compensating for such a drawback, there is an attempt to form a shallow level using a complex center in order to obtain a p-layer, but there has been a problem that selection of a dopant is not easy.

[0005] Conventionally, Journal of the Electrochemical Society, 111, pp805 (1964)
As described above, p-type layers and n-type layers were obtained by growth from a solvent containing Cr as a main component. However, it is considered that a large amount of Cr exceeding the doping level is incorporated in the crystal, and the crystallinity is reduced. For this reason, although the carrier concentration is high, the resistivity is not low, and the method is put to practical use.

[0006]

As described above, in a conventional semiconductor device in which carbon is one of the constituent elements,
There was a problem that a good n-type or p-type semiconductor layer with low resistance could not be obtained, resulting in deterioration of the device due to heat generation and reduction in external quantum efficiency. Particularly, in the conventional SiC light emitting device, there is a problem that the color tone changes due to deterioration of the color tone due to the spread of the emission peak wavelength and the emission wavelength changes depending on the magnitude of the current. In addition, since a low-resistance p-type layer or n-type layer cannot be formed, the light emitting region of the silicon carbide LED is limited to the vicinity of the electrode, and there is a problem in that light is cut off by the electrode and light extraction efficiency is deteriorated. .

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a semiconductor element in which carbon having one of n-type and p-type layers with high carrier concentration and low resistance is one of the constituent elements. I do.

[0008]

In order to achieve the above object, a semiconductor device according to a first aspect of the present invention includes a semiconductor layer of a first conductivity type having carbon as one of constituent elements, and a semiconductor layer of the first conductivity type. The second formed on the layer and having carbon as one of the constituent elements
A semiconductor layer of a conductivity type, wherein the first conductivity type and the second
At least one of the conductive semiconductor layers is doped with a group VIa element.

A semiconductor device according to a second aspect of the present invention comprises an n-type semiconductor layer doped with a group VIa element and having carbon as one of the constituent elements, and a metal layer formed on the surface of the n-type semiconductor layer. It is characterized by the following.

According to a third aspect of the present invention, there is provided a semiconductor device comprising: a first conductivity type semiconductor layer containing carbon as one of constituent elements;
A second conductive type semiconductor layer formed on the conductive type semiconductor layer and having carbon as one of the constituent elements, wherein the first conductive type semiconductor layer comprises a group V element or a group III element and a group VIa element. Are added together.

According to a fourth aspect of the present invention, there is provided a semiconductor device comprising a semiconductor layer in which a group V element or a group III element and a group VIa element are added together and carbon is one of the constituent elements, and a metal layer formed on the semiconductor layer. And characterized in that:

In the third or fourth invention, when both a group VIa element and a group III element are added to the semiconductor layer,
The semiconductor layer shows good p-type conductivity. Further, in the third or fourth invention, when both a group VIa element and a group V element are added to the semiconductor layer, the semiconductor layer exhibits good n-type conductivity.

In the present invention, Cr as a group VIa element,
Mo, W, and the like. In addition, B as a group III element,
Al, Ga, In and the like can be mentioned. In addition, N, P, As, and the like can be given as Group V elements.

In the first or third aspect, a layer such as an i-type conductive semiconductor layer or an insulating layer may be interposed between the first conductive type and the second conductive type semiconductor layers. Second or third
According to the invention, a semiconductor element having good Schottky characteristics and ohmic characteristics can be provided.

The doping amount of the VIa element in the present invention is desirably 5 × 10 ¹⁹ / cm ³ or less in consideration of the fact that the VIa element enters other than the lattice points to prevent dislocation and polycrystallization.

[0016]

The present inventors have conducted research on the growth of group IV semiconductor crystals containing carbon such as SiC and diamond, and found that Cr,
When a group VIa element such as Mo or W is added, 10 ²⁰ / cm ³
It was found that even at a carrier concentration of, the light absorption in the crystal did not increase so much, the color tone of the emitted light did not deteriorate, and there was no wavelength shift due to the magnitude of the current. Heretofore, Si has not been suitable as an added impurity since a group VIa element can be formed only at a deep level even when added. However, from the research of the present inventor, it has been found that in a semiconductor such as SiC and diamond in which carbon is one of the constituent substances, these impurities form a shallow level. Also, it has been found that SiC and diamond films are easily affected by the atmosphere at the time of preparation. Therefore, in the group IV semiconductor layer in which carbon is one of the constituent elements, the group VIa element is an atmospheric component (nitrogen,
It can be presumed that a complex center with oxygen or carbon is formed and a shallow level is formed.

[0017] From the above, in the LED, a high inter-band light transition probability is exhibited and a high luminous efficiency can be obtained. Further, since the activation rate as the donor is remarkably high, a high carrier concentration can be realized with a low impurity concentration.

Further, it has been found that in the liquid phase method, a strong p-type layer can be obtained when a group VIa element such as Cr, Mo or W is added to the p-layer during the growth of the Si solvent. Furthermore, it was also found that a strong n-type layer can be obtained when a group VIa element such as Cr, Mo, W or the like is added to the n layer during the growth of the Si solvent. According to the research by the present inventors, in semiconductors containing carbon as one of the constituent materials, such as SiC and diamond, when a group VIa element and a group III element or a group VIa element and a group V element are added simultaneously, VI
Group a elements were found to produce shallow levels. Also,
From the results of the impurity analysis, the group VIa element is very locally incorporated, and it is unlikely that the impurities distributed in this way improve the electrical characteristics. This is probably due to the fact that it does so or acts as a catalyst during growth.

[0019]

Embodiments of the present invention will be described below. FIG.
In (a) to (d), the first embodiment of the present invention, S
A method for forming an iC: Cr light emitting diode will be described. As a growth method, a liquid phase growth method (LPE) was used. In this embodiment, n-type is used as the first conductivity type and p-type is used as the second conductivity type.
Was doped at 1 × 10 ¹⁹ / cm ³ .

First, the n-type 6HSiC substrate 11 cut out with the (0001) plane as the main surface is doped with Cr, which is a Group VIa element, by the LPE method. An n-type SiC layer 12, which is a group IV semiconductor having carbon as one of the constituent elements, which is very slightly doped with Al, is grown to a thickness of 10 μm. Then, IV containing carbon doped with Al as a constituent element
A p-type SiC layer 13, which is a group semiconductor, is grown to a thickness of about 10 μm (FIG. 1A).

Next, the n-type SiC layer 12 grown on the back surface,
The p-type SiC layer 13 is polished and removed, and a high-concentration n-type SiC layer 14, which is a group IV semiconductor containing Cr-doped carbon as one of the constituent elements, is grown to 2 μm (FIG. 1b).

Further, the high-concentration n-type SiC layer 14 attached to the surface is polished and removed to expose the p-type layer (FIG. 1c).
Thereafter, a Ti / Al electrode 15 is sequentially deposited on the p-type SiC layer 13 from below, and Ni16 is deposited on the n-layer side,
After forming the electrode pattern, heat treatment is performed at 1000 ° C. for 2 minutes to obtain an ohmic contact (FIG. 1D). The Cr-doped n-type SiC layer 12 / p-type SiC layer 13 has a configuration according to the first invention, and the Cr-doped n-type SiC layer 14 / Ni16 has a configuration according to the second invention.

FIG. 2 shows the present embodiment and the Cr in this embodiment.
5 shows an emission spectrum of an LED of a comparative example in which N was added as a donor without adding Nb. The solid line shows the result of the present embodiment, and the broken line shows the result of the comparative example.

In the comparative example, there is light emission near 470 nm and light emission having a wide width on the longer wavelength side. For this reason, visually blue light emission is obtained. However, in this embodiment, the LE
In D, light emission near 460 nm was strong, and a strong light emission peak 21 was obtained on the shorter wavelength side, showing blue light emission that was visually better than the comparative example. In addition, when the color of light was observed by changing the intensity of the current, in the comparative example, the entire broken line was shifted back and forth by the intensity of the current, and the color also changed greatly. Even when it was changed, the emission peak 21 did not shift back and forth, and almost no change in overall color was observed. In the case of this example, the light emission intensity could be controlled by the intensity of the current.

FIG. 3 shows an LED according to the present embodiment and a comparative example.
The relationship between wavelength and transmittance in the epitaxial growth layer of LED is shown. The solid line represents this embodiment, and the broken line represents a comparative example. In this example, Cr was doped, and in the comparative example, N was doped so that both had a carrier concentration of 10 ¹⁹ / cm ³ .

The LED according to the comparative example has a high impurity concentration and the concentration of N as an impurity is as high as 1 × 10 ²⁰ , but the LED according to the present embodiment has a concentration of Cr as an impurity as low as 1 × 10 ^{19, which} is one digit lower.
Cr shows an activation rate of almost 100%.

Further, in the comparative example, the color of the film was greenish and light absorption was large particularly in the blue region and the red region. On the other hand, the one according to the present example showed almost twice the transmittance as compared with the comparative example as can be seen from the graph. This also indicates that the luminous efficiency is significantly improved.

FIG. 4 shows voltage / current characteristics of the present invention and a comparative example. The solid line represents this embodiment, and the broken line represents a comparative example. In the comparative example, since the contact resistance between the n-type substrate and the electrode was high, the diode had a high rising voltage, and the current increasing characteristics were poor even at a rising voltage or higher. This resistance causes heat generation in the diode, and cannot be used with a very high current in practical use. In addition, the one according to the comparative example has a high resistance and causes a large power loss,
This is a factor that lowers the external quantum efficiency. On the other hand, the device according to the present example shows ideal diode characteristics, indicating that a low-resistance electrode was realized. The resistance according to the present example was lower by one digit than that of the comparative example. Further, regarding the electrode for the n-type according to the second invention,
By using a doped layer, the ohmic properties can be improved, and an ohmic electrode can be formed without requiring heat treatment.

Next, an n-type SiC layer doped with Cr was grown by the LPE method, and the relationship between the charged amount and the carrier concentration was measured. FIG. 5 shows the relationship between the charged amount and the carrier concentration when an n-type SiC layer was grown using Cr as a donor in the present example and when N was doped using Si ₃ N ₄ as a dopant as a comparative example. It is shown. The solid line represents this embodiment, and the broken line represents a comparative example.

In the comparative example, the carrier concentration rises to about 10 ²⁰ / cm ^{3 by} adding only 0.3 wt% of Si ₃ N ₄ . Therefore, when Si ₃ N ₄ is used as an additive, in order to form an epi layer having a low carrier concentration, the amount of the additive is reduced and weighing is difficult, so that control is performed at 10 ¹⁸ / cm ³ to 10 ¹⁷ / cm ^3. Was very difficult. On the other hand, when Cr is used, S
Although the rate of incorporation into the iC layer is low, the rate of activation as a donor is high, so that control of the carrier concentration can be relatively easily performed.

FIG. 6 is a sectional view of an LED according to a second embodiment of the present invention. In this embodiment, n-type is used as the first conductivity type and p-type is used as the second conductivity type, and the n-type SiC layer is doped with Cr as a VIa group element as a donor.

1 × 10 ¹⁹ / cm on p-type SiC substrate 61
^A 3Cr-doped n-type SiC layer 62 and a Cr-doped high-concentration n-type SiC layer 63 are sequentially grown. 64 is a Ni electrode, 65 is a Ti / Al electrode, and an ohmic contact is made by heat treatment. p-type SiC substrate 61 / Cr
The doped n-type SiC layer 62 has the structure according to the first invention,
The type SiC layer 63 / Ni electrode 64 has a configuration according to the second invention. In this embodiment, the same effects as those of the first embodiment can be obtained.

FIG. 7 shows a third embodiment of the present invention, in which a Cr-doped n-type diamond film 72 is grown on a p-type diamond substrate 71 by a hot filament CVD method. Cr is doped by heating a solid placed upstream of the source gas. Ohmic contacts are made by heat treatment using platinum paste 73 as the n-side electrode and silver paste 74 as the p-side electrode. It was confirmed that the introduction of Cr as a donor into the n-type diamond film 72 as the light-emitting layer facilitated the formation of the n-type diamond layer, which was conventionally difficult, and increased the luminous efficiency. In addition, this embodiment also has the same effect as the first embodiment.

FIG. 8 shows a fourth embodiment of the present invention.
This is a MOS transistor made using In the figure, reference numeral 81 denotes a p-type SiC substrate containing Ga. Reference numeral 82 denotes an n-type SiC layer formed by ion-implanting As and Cr into the substrate 81. In such a structure,
An O ₂ film 83 is laminated using a known CVD method. Reference numeral 84 denotes an Al film which will be a gate electrode in the present transistor. 8
Reference numeral 5 denotes a Cr film which forms an ohmic electrode for the n-type SiC. When the characteristics of the p-channel transistor having such a structure were examined, the electric resistance at the source electrode and the drain electrode was suppressed to be low, and the switching speed and the power consumption were remarkably improved as compared with those not doped with Cr. As described above, the present invention can be used as an ohmic electrode forming layer of various semiconductor devices other than the LED.

It should be noted that the present invention relates to a group VIa element such as Cr, Mo, W, a group III element such as N, P, As or a group V element B, Al, An efficient LED can be manufactured by using any combination of Ga and In. Also, when only an element of group VIa such as Cr is doped into an IV semiconductor layer containing carbon as one of the constituent elements, a purple LED can be produced with an emission peak on the short wavelength side as the center. When the p-type layer is used as the light-emitting layer, the p-type layer is doped with an impurity such as Al as an acceptor layer and, at the same time, is doped with Cr or the like.
The effects of the present invention can be sufficiently exerted by doping the group VIa element. In this case, it is necessary to dope a Group VIa element so as not to exceed the concentration of the acceptor. For example, Al is used as an acceptor at 2 × 10 ¹⁹ / cm 2.
³ , p-type SiC doped with about 5 × 10 ¹⁸ / cm ³ of Cr as a group VIa element provides a good light emitting layer. The metal used for the ohmic electrode according to the present invention includes Cr, Ni, Ta, Mo, and the like.

Next, FIGS. 9 and 10 show a fifth embodiment of the present invention.
A description will be given of a SiC light emitting diode which is an embodiment of the present invention. FIG. 9 is a cross-sectional view of the SiC light emitting diode of this embodiment.
As a growth method, a liquid phase growth method (LPE) having a temperature difference as shown in FIG. 10 was used. In the figure, 101 is a graphite crucible, 102 is a heat shield, 103 is a Si solvent, 10
4 is a graphite support, 105 is a holder, and 106 is a water-cooled chamber.

First, in a high-purity graphite crucible 101, polycrystalline Si and 0.003 wt.
% Silicon nitride and 2 wt.
Raise the temperature to 650 ° C. As shown in the graph, crucible 101
Is adjusted so that the temperature becomes higher and the temperature becomes lower as it goes up and down. An n-type 6HSiC crystal substrate 91 cut into the (0001) plane is placed at the center of the crucible 101 and the substrate surface is etched. Then, the substrate is placed near the bottom of the crucible and n-type S
The iC layer 92 is grown to 10 μm.

Next, the crucible 101 was replaced with a polycrystalline Si,
1 wt.% Cr of the amount of Si as a group VIa element and 2 wt.% Al as an acceptor impurity are added, and the temperature is raised to 1650 ° C. As in the case of growing the n-type SiC layer 92, the p-type SiC layer 93 (carrier concentration: 1 × 1) is sequentially placed in a high-temperature region and a low-temperature region, and is doped with both Al and Cr as a p-type layer.
0 ¹⁹ cm ⁻³ ) is grown to about 10 μm. In this method, the p-type SiC layer is epitaxially formed on the front surface of the n-type SiC layer 92 and the back surface of the n-type 6HSiC crystal substrate 91.
The epitaxial layer grown on the back surface of the mold 6HSiC crystal substrate 91 is removed by polishing.

Next, on the p-type SiC layer 93, Ti, A
194 was sequentially deposited, and Ni95 was deposited on the n-type 6HSiC crystal substrate 91 side to form an electrode pattern.
Heat treatment was performed at 00 ° C. for 2 minutes to form an ohmic junction to form an electrode.

FIG. 11 shows a near-field pattern of a light-emitting diode when a p-type layer is formed by adding only Al without adding Cr as a comparative example of the present embodiment.
The solid line represents this embodiment, and the broken line represents a comparative example.

In the comparative example, since the resistance of the p-type layer was high, the diode emitted light only in the vicinity of the electrode, and the emitted light was hidden by the electrode, resulting in poor light emission intensity. On the other hand, in this example, the light emitting region was wide in the lateral direction far from the electrode, and thus the light emitting intensity was high.

In the comparative example, the p-type layer has a very high resistance, causing heat generation in the diode, and cannot be used with a very high current in practical use. In addition, the power loss is increased, which is a factor that lowers the efficiency. On the other hand, according to the present embodiment, the above-mentioned various characteristics were improved, and a diode having a low series resistance, which was difficult in the past, could be manufactured.

FIG. 12 is a sectional view of a Schottky diode according to a sixth embodiment of the present invention. Fig. 10
Was used. First, an n-type SiC layer 122 was epitaxially grown on an n-type 6HSiC crystal substrate 121. In this case, N is used as a donor, and Cr is used as a VIa group element.
Was simultaneously added to the silicon solvent. Carrier concentration is 1 ×
10 ¹⁷ / cm ³ .

Next, a Ni electrode 124 was deposited on the back surface of the n-type 6HSiC crystal substrate 121 and alloyed to form an ohmic electrode, and an Au electrode 123 was deposited on the n-type SiC layer 122 to form a Schottky electrode.

FIG. 13 shows the current-voltage characteristics of a Schottky diode in which only N was added without adding Cr and an n-type layer having the same carrier concentration was formed as a comparative example of this embodiment. The solid line represents this embodiment, and the broken line represents a comparative example.

In this embodiment, the breakdown characteristics in the reverse direction are superior to those of the comparative example. This is because, in this embodiment, the activation rate of N as a donor is increased by adding Cr, and no extraneous impurities are retained in the crystal, so that the n-type SiC layer 122 has few crystal defects. .

The Schottky diode using the Schottky junction shown in FIG. 12 is also used as an ultraviolet ray detector. However, according to the present embodiment, the N impurity can be reduced by almost one digit as compared with the prior art, and the sensitivity to ultraviolet rays is greatly increased. I can expect that.

FIG. 14 shows a seventh embodiment of the present invention (A
It is a sectional view of a double hetero type light emitting diode using (IN) _x (SiC) _y . The growth apparatus shown in FIG. 10 was used.

First, an n-type (AlN) _0.6 (SiC) _0.4 layer 142 (carrier concentration: 1 × 10 ¹⁸ / cm ³ ) doped with N as a donor impurity and Cr as a group VIa element on an n-type 6HSiC crystal substrate 141. Is epitaxially grown, and then the (AlN) _0.5 (SiC) _0.5 active layer 143 is formed.
(Carrier concentration: 1 × 10 ¹⁶ / cm ³ ) was epitaxially grown. Next, as a p-type layer, p-type (A) doped with Al as an acceptor impurity and Cr as a group VIa element.
1N) _0.6 (SiC) _0.4 layer 144 (carrier concentration 1)
× 10 ¹⁸ / cm ³ ) was epitaxially grown.

Next, p-type (AlN) _0.6 (SiC) _0.4
Ti and Al 145 are sequentially deposited on the layer 144, Ni 146 is deposited on the n-type 6HSiC crystal substrate 141 side, and an electrode pattern is formed. .

As described above, by using the present invention, it is possible to increase the carrier concentration of the n-type layer and the p-type layer, which has been difficult in the past, and to realize a DH (double hetero) structure having high luminous efficiency. Now you can make it.

FIG. 15 is a sectional view of an ultraviolet CCD according to an eighth embodiment of the present invention. First, the p-type SiC crystal substrate 15
An n-type region 152 is formed on one surface. Next, a thermal oxide film is formed on crystal substrate 151. Then, the n-type region 1
A hole is selectively formed only in the portion 52 to form a platinum electrode 153 which is an ohmic electrode. Next, this platinum electrode 1
53 and N as a donor impurity and Cr as a group VIa element
To form an n-type SiC amorphous semiconductor layer 154 to which Si is added. Thereafter, a high-resistance n-type layer 155 compensated by Al is grown. Further, on this high-resistance n-type layer 154, a wide gap AlN and SiC mixed crystal amorphous layer 15 doped with N as a donor impurity and Cr as a Group VIa element is formed.
6 is formed. In the figure, 157 is a charge transfer gate, 158
Is an SiO insulating film.

Of the layers thus formed, n-type S doped with N as a donor impurity and Cr as a group VIa element was used.
iC amorphous semiconductor layer 154, AlN and SiC
The mixed crystal amorphous layer 156 was able to reduce the resistance.

Since the ultraviolet CCD of this embodiment has high sensitivity and is transparent to visible light, it is possible to capture an image at a wide wavelength with a laminated structure with the visible CCD. Next, as a method of realizing the low-resistance semiconductor layer of the present invention, a method of growing a SiC layer by MBE will be described. FIG.
Is a growth apparatus of the MBE method. In the figure, 161 is a chamber, 162 is a heater, and 163 is a Cr source.

First, the susceptor 164 has the SiC substrate 16
5 and a Cr layer 166 on the SiC substrate 165.
Is grown by several atomic layers. Then acetylene, disilane,
Flowing a gas of trimethylaluminum for doping,
A SiC layer 167 is grown. At this time, the Cr layer is a SiC layer 1 due to a surface migration (surface diffusion) phenomenon.
Move to the growth surface of 67. However, some Cr is SiC
The layer which is left in the crystal of the layer 167 and is doped with both the acceptor impurity Al and the group VIa element Cr is grown. The layer grown in this way can exhibit a p-type with a high carrier concentration.

The present invention is not limited to the embodiments described above. In the present invention, Cr, M
group VIa elements such as o and W, and group V elements N, P, As, and group III elements B,
Since any of Al, Ga, and In can be used in any combination, an efficient semiconductor element containing no extra impurities can be manufactured. In addition, various modifications can be made without departing from the spirit of the present invention.

[0057]

As described above, according to the present invention,
A p-type or n-type conductivity semiconductor layer having a high carrier concentration and a low resistance can be realized, which can contribute to the improvement of the performance of various semiconductor elements.
In particular, the color tone is significantly improved, and it is possible to realize a group IV semiconductor device that does not change color due to the magnitude of the current.
The display characteristics of the display element can be improved and the range of colors that can be displayed can be greatly expanded. Also, since ohmic contact between the n-type group IV semiconductor and the metal can be realized with extremely low resistance,
The characteristics of the group IV semiconductor device can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view illustrating a manufacturing process of a light emitting diode according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a relationship between a wavelength and a light emission intensity of the light emitting diode according to the first embodiment of the present invention and a light emitting diode of a comparative example.

FIG. 3 is a diagram illustrating a relationship between a wavelength and a transmittance of the light emitting diode according to the first embodiment of the present invention and a light emitting diode of a comparative example.

FIG. 4 is a diagram showing voltage-current characteristics of the light emitting diode according to the first embodiment of the present invention and a light emitting diode of a comparative example.

FIG. 5 is a diagram showing the relationship between the charged amount of additives and the carrier concentration of the light emitting diode according to the first embodiment of the present invention and the light emitting diode of the comparative example.

FIG. 6 is a sectional view of a light emitting diode according to a second embodiment of the present invention.

FIG. 7 is a sectional view of a light emitting diode according to a third embodiment of the present invention.

FIG. 8 is a sectional view of a MOS transistor according to a fourth embodiment of the present invention.

FIG. 9 is a sectional view of a light emitting diode according to a fifth embodiment of the present invention.

FIG. 10 is an explanatory view of a crystal growth apparatus used in the present invention.

FIG. 11 is a view showing a near-field pattern of a light emitting diode according to a fifth embodiment of the present invention and a light emitting diode of a comparative example.

FIG. 12 is a sectional view of a Schottky diode according to a sixth embodiment of the present invention.

FIG. 13 shows the voltage and voltage of the Schottky diode according to the sixth embodiment of the present invention and the Schottky diode of the comparative example.
The figure showing a current characteristic.

FIG. 14 shows a (AlN) _{x according} to a seventh embodiment of the present invention.
Sectional drawing of the double hetero type light emitting diode using (SiC) _y .

FIG. 15 is an ultraviolet CCD according to an eighth embodiment of the present invention.
FIG.

FIG. 16 shows an example of S by MBE according to an embodiment of the present invention.
Diagram showing a method of growing an iC layer

[Explanation of symbols]

 Reference Signs List 11 n-type SiC substrate 12 Cr, Al-added SiC epitaxial layer 13 p-type SiC layer 14 Cr-added n-type SiC layer 15 Ti / Al: electrode layer 16 Ni electrode layer 91 n-type SiC substrate 92 Cr, Al-added n-type SiC epitaxial Layer 93 p-type SiC epitaxial layer 94 Ti / Al: electrode layer 95 Ni electrode layer

────────────────────────────────────────────────── ─── Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 33/00 JICST file (JOIS)

Claims (8)

(57) [Claims] 1. A semiconductor layer of a first conductivity type having carbon as one of the constituent elements, a semiconductor layer of a second conductivity type formed on the semiconductor layer of the first conductivity type and having carbon as one of the constituent elements, And a group VIa element is added to at least one of the semiconductor layers of the first conductivity type and the second conductivity type. 2. A semiconductor device comprising: an n-type semiconductor layer to which a group VIa element is added and carbon is one of the constituent elements; and a metal layer formed on the surface of the n-type semiconductor layer. . 3. A semiconductor layer of a first conductivity type having carbon as a constituent element, a semiconductor layer of a second conductor type formed on the semiconductor layer of the first conductivity type and having carbon as a constituent element. Wherein the semiconductor layer of the first conductivity type is a group V element or
A semiconductor device, wherein a group III element and a group VIa element are added together. 4. A semiconductor device comprising: a semiconductor layer in which a group V element or a group III element and a group VIa element are added together and carbon is one of constituent elements; and a metal layer formed on the semiconductor layer. Semiconductor element. 5. AlN and Si doped with a group VIa element
Semiconductor, characterized by comprising a C mixed crystal amorphous layer
Body element . 6. The semiconductor to which the group VIa element is added
5. The method according to claim 1, wherein the layer is a SiC layer.
The semiconductor device according to any one of the above. 7. The semiconductor to which the group VIa element is added
The layer is composed of an epitaxial layer containing AlN and SiC.
5. The method according to claim 1, wherein the layer is a long layer.
Semiconductor element. 8. The semiconductor to which the group VIa element is added
The layer of claim 1, wherein the layer is a diamond layer.
Or the semiconductor device according to 2.