TW200400674A - Nitride semiconductor laser device and manufacturing method thereof - Google Patents

Abstract

This invention provides a nitride semiconductor laser element which is provided with high-output type resonator end surfaces and which has a resonator containing an active layer consisting of an In-containing nitride semiconductor between an n-type nitride semiconductor layer and a p-type semiconductor layer, in which an end surface film, consisting of a single crystal AlxGa1-xN (0 ≤ x ≤ 1) that is formed at low temperatures not damaging the active layer consisting of the In-containing nitride semiconductor, is formed on at least an outgoing end surface out of the opposing resonator end surfaces of the laser element.

Description

(i) (i) 200400674 (1) Description of the invention (The description of the invention shall state: the technical field to which the invention belongs, the prior art, the content, the embodiments, and the drawings are simply explained.) TECHNICAL FIELD The present invention relates to the Crystal 1) A nitride semiconductor laser device formed by an end film. BACKGROUND ART A semiconductor laser device using a GaAs-based semiconductor, which has been widely used in the past, has a window structure in which a protective film is formed on an end face of a resonator, so that the laser device can have a long life. In the nitride semiconductor laser device, because the energy gap of the resonator end face formed by the nitride semiconductor by RIE (reactive ion etching) or cleaving is small, the absorption of the emitted light occurs at the end face, and the absorption occurs at the end face Heat, in order to achieve high output lasers above 100 mW has the problem of life characteristics. Therefore, a method for forming a window structure on a nitride semiconductor laser element as a protective film to form an AlGalnN semiconductor film (Japanese Patent Application Laid-Open No. 7-249830) and a method for forming a protective film such as A1N (Japanese Patent Application Laid-Open No. 2002-26442) have been proposed. DISCLOSURE OF THE INVENTION (Problems to be Solved by the Invention) However, as shown above, a protective film formed by a vapor phase growth method to form a single crystal requires a growth temperature of 1000 ° C or higher. The required growth temperature will damage the active layer containing In. . Therefore, if the protective film is formed at a temperature that does not damage the active layer, the protective film becomes amorphous. When the amorphous protective film is used for the window structure of a semiconductor laser device, the light emitted by the crystal is not a single crystal and is scattered. The shape of the laser beam cannot be uniform. Moreover, the amorphous color will cause light absorption and There is a problem that the end face is deteriorated due to heat generation. Therefore, the present invention, in order to solve the above-mentioned problem, provides nitrogen having an end face film formed by a single crystal AlxGa ^ NW ^ 1) which does not impart activity to the 400200674 Invention Description Continued (2) layer damage and does not cause the above-mentioned problem. For semiconductor laser devices. (Solution) The nitride semiconductor laser device of the present invention includes a resonator between the n-type nitride semiconductor layer and the p-type semiconductor layer, and includes a resonator formed of a nitride semiconductor containing In. A nitride semiconductor laser element with an active layer of at least an exit end surface of a resonator end face opposite to the laser element, forms a single-crystal AlxGa formed at a low temperature that does not damage the active layer formed by the nitride semiconductor containing In. ^ NCO ^ 1) The end film formed. Here, the low temperature at which the active layer made of a nitride semiconductor containing In is not damaged is the formation temperature of the active layer made of a nitride semiconductor containing In. The active layer formed of a nitride semiconductor containing In is usually grown at a growth temperature of 900 ° C. As long as the growth temperature is below the growth temperature, it is not damaged by the decomposition of the active layer. Therefore, the growth temperature of the end film is below 900 ° C, preferably below 600 ° C, and more preferably below 500 ° C. In the nitride semiconductor laser device of the present invention, a resonator containing an active layer made of a nitride semiconductor containing In refers to a light-guiding region, and is generally composed of an active layer and a light-guiding layer. Therefore, at least the above-mentioned resonator end surface region may be formed on the end mask of the present invention. The aforementioned active layer is composed of a single or multiple quantum well structure containing at least one InGaN well layer or InAlGa well layer. The end film of the present invention is composed of a single crystal AlxGahNWg 1). The mixed crystal ratio is determined by the relationship with the function of the end film. That is, since the energy gap of the exit end face of the continuation layer is explained by the invention in 2004200674 (3), it is narrowed by etching or cleaving when the exit end face is formed. The energy gap determines the mixed crystal ratio. In consideration of the crystallinity of the end film, the A1 mixed crystal ratio is preferably 0.3 or less, and preferably 0.1 or less. With regard to the nitride semiconductor laser device of the present invention, the film thickness of the front end film is preferably 50 A or more, but in order to ensure the uniformity of the end film, it is preferably 2000 A or less. In the present invention, in order to form the single crystal AlxGauNCOS 1) at the low temperature described above, the AMMONO method is applied. The method of forming the XS 1) single crystal layer in a supercritical state of ammonia on a specific seed surface (on the resonator surface of the laser device of the present invention). The above-mentioned single crystal end film can be formed on the surface by using the AMMONO method. 900 ° C or less, preferably 600 ° C or less, and more preferably 500 ° C or less. The AMMONO method is usually affected by the composition of the high-pressure reactor, and the aforementioned end film contains at least one selected from the group consisting of Ni, Cr, Co, Ti, Fe, Al, Si, and Mη. In addition, the aforesaid end face film, as a feature of the AMMONO method, contains at least one Group 1 (IUPAC. 1989) element Li, K, Na, or Cs as a mineralizer. Because the aforementioned end face film does not absorb the light emitted from the aforementioned nitride semiconductor laser device, it does not absorb heat from the output end face. A nitride semiconductor laser device above 100 mW can suppress the generation of COD. The nitride semiconductor laser device is formed on a GaN substrate, a sapphire substrate, a spinel, a ZnO substrate, a SiC substrate, or other hetero substrates such as a sapphire substrate. The ELO substrate is grown on the surface by the lateral growth of GaN. A substrate formed of a substrate of a nitride semiconductor having unevenness is selected. Here, the so-called EL0 (Epitaxial-Lateral-Overgrowth) substrate is a substrate that uses GaN to grow laterally to reduce the difference. -In the supercritical ammonia, a GaN substrate is preferred in the present invention where AlxGai ^ N (0S 丨) is grown as an end film. When a nitride semiconductor laser with a heterogeneous substrate different from the end film is used, the semiconductor of the end film which is dissolved and recrystallized in supercritical ammonia during the formation of the end film is mixed with the semiconductor to avoid impurities. The GaN substrate is a GaN substrate or the like grown in supercritical ammonia. A semiconductor laser element grown on a substrate different from a nitride semiconductor is difficult to cleave at the step of the device. This is because the heterogeneous substrate due to the growth of GaN is not cleaved. However, since the GaN substrate has cleavability, it is possible to form the GaN substrate with a cleaved end surface which is better than a mirror surface when opening a resonator. And because it is a homogeneous epitaxial growth, it can control the warpage of the laser device after the growth. With this, the occurrence of cracks will disappear. The growth surface of the GaN substrate that forms a laser element is usually c-plane. The substrate is obtained by the vapor phase growth method. According to the AMMONO method, GaN bulk single crystals are grown in the supercritical ammonia in the C-axis direction by a thickness of 2 · 5 ，, and can be cut to obtain GaN single crystals with an A-plane or an M-plane as the main plane i or more inches. Substrate. The octahedron or M-plane is non-polar, so it does not polarize the active layer. And the defect density is about 104 / cm2 or less. In addition, the polarity conversion of the GaN substrate with the (〇〇 (M) plane as the main plane) can make the (0001) plane of the c-plane the main plane. If the nitride semiconductor laser element is formed on the c-plane of the GaN substrate, the aforementioned The end film is formed on the M or A surface and can be used as a non-polar end film. If the nitride semiconductor laser device is formed on the A surface of a GaN substrate grown in supercritical ammonia, the laser device will not be given. The active layer is polarized, and the exit surface of the resonator is formed! The surface is formed on the M surface, which is beneficial for cleaving. If the foregoing nitride semiconductor laser element is formed by the invention of Super Pro-10-200400674 I It is explained that the M surface of the GaN substrate grown in ammonia on the continuation page will not give the active layer polarization effect of the laser element, and an end film can be formed on the A surface which is non-polar to the emitting surface of the resonator.

The present invention is to provide a method for manufacturing a nitride semiconductor laser device. A resonator is provided between the n-type nitride semiconductor layer and the p-type semiconductor layer, and contains a nitride of an active layer formed of a nitride semiconductor containing In. A method for manufacturing a semiconductor laser element, comprising: a first step of etching or cleaving the aforementioned laser element to form an opposite end face of the resonator; at least the exit end face of the opposite end face of the laser element The second step of forming an end face film formed of an end face made of AlxGa ^ N ^ S 1) single crystal formed at a low temperature that does not impart damage to the aforementioned active layer.

In the aforementioned second step, a single crystal X $ 1) can be formed at a low temperature without causing damage to the active layer by forming a front-emitting end film in supercritical ammonia. The aforementioned second step (2) is characterized in that it comprises forming at least the p-type contact layer on the resonator with a mask having a solubility in supercritical ammonia equal to or lower than that of the end film, and then forming the end film. The formation of the mask can prevent the resonator of the laser element from dissolving from the upper surface of the p-type contact layer and the corner of the end surface when the end film of the nitride semiconductor laser element is formed in super-soluble supercritical ammonia. The mask is preferably selected from the group consisting of silicon oxide, silicon nitride, aluminum nitride, manganese, and tungsten. Since these masking materials are more stable than GaN in supercritical ammonia, the contact surface of the area covered by the masking materials can inhibit dissolution. The mask can be easily removed when the ridges are formed in a later step. In the manufacturing method of a front-emitting nitride semiconductor laser device, the aforementioned end face -11-200400674 (6) Description of the Invention Continued Film, the film formation temperature in supercritical ammonia is 100 ° C to 900 ° C. The nitride semiconductor laser device has an active layer as a quantum well structure containing InGaN, and the layer growth on the active layer at a temperature higher than 900 ° C may cause the active layer to be decomposed. According to the present invention, the end face film can be grown at a temperature of 900 ° C or less, preferably 600 ° C or less. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of an end face of a nitride semiconductor laser device according to the present invention.

Illustration. 2A to 2D are cross-sectional views showing manufacturing steps when an end film is formed without a mask on both end surfaces. 3A to 3E are cross-sectional views showing the manufacturing steps of an end face film of a nitride semiconductor laser device according to an embodiment of the present invention. Fig. 4 is a cross-sectional view of a crystal circle according to an embodiment of the present invention when a protective film is formed on a substrate.

5A to 5E are explanatory diagrams of steps when a cleaved nitride semiconductor laser device is applied to the present invention. Best Mode for Carrying Out the Invention Embodiments of the present invention will be described below. FIG. 1 is an end sectional view of a nitride semiconductor laser device according to the present invention. An n-type nitride semiconductor layer 2 and a p-type nitride semiconductor layer 4 are laminated on a sapphire substrate, and a nitride containing In is formed therebetween. Active layer 3 with a single or multiple quantum well structure. In this way, a laser device with good luminous efficiency can be obtained from the near-violet to the green wavelength range of visible light (370 nm to 550 nm). η-type nitride semiconductor layer 2 is composed of η-contact layer-12- (7) (7) 200400674 Description of the invention continued on page 21, crack prevention ~ layer 22, n-type cladding layer 23 and n-type light guide layer 24 . In the case where the guinea pig prevention layer 22 uses a GaN substrate, the warpage of the wafer can be suppressed, and the p-type nitride semiconductor layer 4 can be omitted. The cap layer 4m, the p-type light guide layer π, and the P-coated layer 43 can be omitted. The P contact layer 44 is formed. Here, the above-mentioned sapphire substrate 丨 may also be formed with an ELO layer as a differential defect reduction layer or via an AlGaN layer for the purpose of reducing pits. In the above-mentioned embodiment, the resonator of the semiconductor laser device is composed of the above-mentioned active layer 3 and the p-type layer and the n-type light guide layer 24, 42 or the cap layer 41. The exit end of the resonator end face: = an end face film P made of single crystal AlxGai_xN⑽⑸) is used to form the saki mask on the light reflection side of the resonator end face (Fig. 2), which can suppress deterioration of the end face due to reflected light. Hereinafter, three typical manufacturing methods of the nitride semiconductor laser device according to this embodiment will be described. FIGS. 2A to 2D show the steps of placing an end face film on both end faces of a resonator without forming a mask, and FIGS. 3A to 3E show the steps of forming an end face film on an exit end face with a peripheral mask on both end faces of the resonator. ~ 5E is the output end surface of the display resonator, and the shape of the output end surface is formed by cleaving after the electrode is opened. Next, a peripheral mask is formed on the end face, and an M-face end face film is formed on the exit end face, followed by a step of forming a laser element by cleaving or the like. In the first method shown in FIG. 2, first, a low-temperature-growth buffer layer u formed on the sapphire substrate i is prepared, and an n-type nitride semiconductor layer 2 and an active layer are formed on the buffer layer ^. -Type nitride semiconductor layer-13- 200400674 (8) Description of the invention Continuation page 4 Wafers grown in sequence (Figure 2A). Here, growing the n-type nitride-silicon semiconductor layer 2 through the ELO layer on the low-temperature buffer layer 11 can reduce defects. Next, the above-mentioned wafer was exposed to the resonator end face and the η-contact layer 21 by wet etching (Fig. 2B). Thereafter, the end film 5 was formed by applying the AMMONO method to the wafer on which the end surface of the resonator was exposed.

In the high-pressure reactor, the raw material for the end film and the mineralizer as the reaction promoter are set together with the wafer, and ammonia is put into the supercritical state by performing specific temperature management.

The aforementioned wafer is a wafer in which an n-type nitride semiconductor layer 2, an active layer 3, and a p-type nitride semiconductor layer 4 are sequentially grown on a sapphire substrate 1, and replaced by 'removing a heterogeneous substrate such as a sapphire substrate. Wafer 'substrate 1 is a wafer in which n-type nitride semiconductor layer 2, active layer 3, and p-type nitride semiconductor layer 4 are sequentially grown, and only the reflected light side of the resonator end face is not dissolved or even dissolved by supercritical ammonia The material that is not mixed into the end face film can be, for example, a wafer that masks 6 with Ag, etc., and the wafer that completely covers the exit end face of the resonator end face with Ag, etc., and only covers the wafer with the aforementioned substrate ( Figure 4). The solubility of GaN in the aforementioned supercritical ammonia is high. If a mask is not formed on the surface of the p-type nitride semiconductor layer 4, the nitride semiconductor element will be dissolved from the corners of the outermost surface and the emission end surface. Therefore, the p-type contact layer on the outermost surface of the p-type nitride semiconductor layer 4 is masked. The masking material is selected from the group consisting of stone oxide, silicon nitride, aluminum nitride, manganese, and tungsten. These masking materials are more stable than GaN in supercritical ammonia and can suppress the dissolution of GaN. Forming a mask on the p-type contact layer in this way means that the dissolution of the corner portion of the p-type contact layer and the exit end face can be suppressed. It is also preferable that the step after the formation of the end face film is easy to remove. The cover -14-200400674 (9) Description of the invention Continued The film thickness of the cover is 1 μm or more. After the wafer shown above was reacted in a high-pressure reactor, the wafer was formed on the exposed surface of the nitride semiconductor layer with an end film made of single crystal AlxGahNiOS 1) (Fig. 2C). Next, the end face film on the p-type nitride semiconductor layer 4 is taken out, the protective film is formed on the exit end face, a reflective film is formed on the opposite side, and a laser device is cut out by the groove portion. Here, the protective film and the reflective film may be made of the same material, and formed of Si02, Ti02, or a plurality of films having a protective effect and a reflective effect. In the second method shown in FIG. 3, first, an n-type nitride semiconductor layer 2 on the C surface of the GaN substrate 1 is prepared, that is, an n-contact layer 21, a crack prevention layer 22, an n-type cladding layer 23, and an n. A photoconductive layer 24, followed by an active layer 3, and a p-type nitride semiconductor layer 4, that is, a top growth layer 41, a p-type photoconductive layer 42, a p-type cladding layer 43, and a p-contact layer 44 are sequentially grown (FIG. 3A) . Here, since the GaN substrate is used, it is not necessary to grow the n-type nitride semiconductor layer 2 via the ELO layer on the low-temperature buffer layer 11 as in the first method, and the defects of the suspended layer can be reduced. Next, the above-mentioned wafer is exposed by the wet etching to the resonator end surface and the η-contact layer 21, and a mask 7 is formed in addition to the exit surface of the resonator end surface (Fig. 3B). Thereafter, the end film 5 is formed by applying the AMMONO method to the wafer on which the end surface of the resonator is exposed (FIG. 3C). Next, after the end-face film is formed, the mask 7 is removed, and a ridge shape is formed in a general element process (Fig. 3D). The ridge-like stripe that conducts the light guide wave is formed in the direction of the resonator. The width of the ridge is 1.0 to 20 μΐη, and the depth of the ridge is to reach the p-type cladding layer or p-type light guide layer. Thereafter, as a ridge, a filling layer 70 made of a Zr02 film is formed. Ground contact with ridge-shaped p-type contact layer 44 > 15- 200400674 (ίο)

A p-type ohmic electrode 80 is formed. The number of the ridges is not limited to a singular number, and a plurality of ridge-shaped laser elements may be formed. Next, on the surface of the n-type contact layer 21, an n-electrode 90 and a p-electrode are formed in parallel. Next, a ρ- 塾 electrode 11 0 and an n-pad electrode 2 20 are formed. In addition, by alternately patterning Si02 and Ti02 to form, for example, covering the entirety of the ρ electrode and the η electrode, the Si02 / Ti〇2 insulating film functions as a reflective reflection film 100 for the laser. Finally, it is divided into individual nitride semiconductor laser devices by dicing. A semiconductor laser device can be manufactured as described above (Fig. 3E, Fig. 1). It is also possible to shoot a protective film on the end face film in order to resonate efficiently. This protective film has a refractive index difference from AlGaN of the end film. Specifically Nb, Ni, Cr, Ti, Cu, Fe, Zr, Hf, W, Rh, Ru, Mg, A1, Sc, Y, Mo, Ta, Co, Pd, Ag, Au, Pt, Ga, and then These are oxides, nitrides, compounds, etc. 5A to 5E show the steps of obtaining the laser element by cleaving using the A surface of the GaN substrate 1 as the substrate and the M surface as the exit end surface as a third method. to

A nitride semiconductor laser is formed on this GaN substrate 1 in the same manner as in the second method. The same parts are assigned the same reference numerals and descriptions are omitted. Next, the r-type contact layer 21 is exposed by etching (FIG. 5A). Thereafter, a ridge shape is formed (Fig. 5B), and a p-type ohmic electrode 80 is formed in contact with the p-type contact layer 44 at the uppermost portion of the ridge shape. Next, an n-electrode 90 is formed on the surface of the n-type contact layer 21. Next, the? -Pad electrode 110 and the? -Pad electrode 120 are formed (Fig. 5C). Next, the exit end face is formed by cleaving. As a result, the wafer is rod-shaped. Thereafter, the end face film 5 is formed in supercritical ammonia (FIG. 5D). This is split to make a laser element (Figure 5E). The so-called AMMONO method system using supercritical ammonia and the gallium nitride system compound-16-200400674 (11) I. Description of the invention The method for growing a nitride semiconductor showing a negative solubility curve in a supercritical state of ammonia-, There are detailed records in Polish applications (P-347918 and P-350375) and PCT applications (PCT / IB02 / 04185), and practitioners can easily implement the present invention by referring to the following description and examples.

For the explanation of the method, the above-mentioned negative solubility curve means that in the reaction system, the solubility of the nitride semiconductor in the high temperature region is low, the solubility of the nitride semiconductor in the low temperature region is high, and the high temperature region is formed in the high pressure reactor. With the low temperature region, the temperature is appropriately managed, the nitride dissolves on the other side of the low temperature region, and the nitride recrystallizes in the high temperature region. By allowing the low temperature region to convect the high temperature region, the nitrogen in the high temperature region will be condensed. The compound maintains a specific concentration, and the growth of the nitride is selectively performed on the seed crystal.

Therefore, the above-mentioned wafers are arranged in a high-temperature region within the reaction system of the high-pressure reactor, and the feed is arranged in a low-temperature region. In this way, the feed in the low temperature region is first dissolved to form a supersaturated state. Secondly, convection occurs in the reaction system, and the dissolved feed flows to the high temperature region. Due to the low solubility in this high temperature region, the dissolved feed will recrystallize on the seeded wafer. By this recrystallization, the present invention forms an end face film. In addition, since this method does not grow the nitride semiconductor at a temperature of 900 ° C or higher, such as the vapor phase growth of a nitride semiconductor, it is preferably 900 ° C or lower, preferably 600 ° C or lower, and more preferably 500 ° C or lower. It is more suitable for low-temperature growth of nitride semiconductors as a feature, and does not cause the In-containing active layer of a wafer disposed in a high-temperature region to be decomposed by heat.

The above feed varies according to the composition of the end face film, but the end face film is formed of GaN -17- 200400674 (12) Description of the Invention When the continuation sheet is formed, GaN single crystal or polycrystal is generally used, or GaN precursor or Ga metal is used. Once GaN single crystal or polycrystal is formed, it can be recrystallized. GaN can be formed by a vapor phase growth method such as HVPE method or MOCVD method, or formed by an AMMONO method, a melting method, or a high-pressure method. In the case of A1N, as in GaN, A1N single crystal or polycrystal is used, or A1N precursor or A1 metal is used. Once A1N single crystal or polycrystal is formed, it can be recrystallized.

In the case of AlGaN, since it is a eutectic of A1N and GaN, the two materials are appropriately mixed and used, and metal and single crystal or polycrystalline (for example, A1 metal and GaN single or polycrystalline) are used. By using two or more mineralizers, a specific composition can be obtained. The above mineralizers can be alkali metals (Li, Na, K, Cs), or alkali metal complexes (metal test amines, metal test imines). Here, the molar ratio of the aforementioned metal test to ammonia is 1: 200 to 1: 2, and Li is preferably used. Since Li is a mineralizer with low solubility, it can suppress the dissolution of the exposed end face, and it is suitable for forming a thin end face film of 50 A or more and 1 μm or less. The high-pressure reactor is mainly composed of an alloy made of Ni, Cr, and Co, but contains other Ti, Fe, Al, Si, Mn, and the like. Here, the thickness of the end face film 5 made of single crystal AlxGai_xN is preferably 50 A or more. Since this film thickness is thinner than 50A, the effect of flattening the etched end face becomes small. Moreover, as an upper limit of a film thickness, what is necessary is just the film thickness which a practitioner can implement. Furthermore, in the present invention, the end-face film is grown on the strip-shaped side and end surfaces and on the surface of the n-type contact layer 21, but at least the film on the surface of the n-type contact layer 21 so as not to stripe the active layer The buried ground stops growing below -18 μm to -18- (13) (13) 200400674 I states that the continuation sheet should preferably reduce the A1 mixed crystal because the end film 5+ »4 is effectively flattened. However, if the effects of the present invention and A and S are the same, only a small amount of crystals will be mixed. A / Kunjing can also be zero, μ, * face month 旲 5 is AlxGaNxN, 0 ^ χ ^ 0.3 is more suitable χ $ 〇 · 15 is more suitable. After the etching, the strip-shaped side surface and the end surface can be grown to form a smooth surface close to the mirror surface on the side surface and the end surface. That is to say, the shape j has a relatively uneven surface on the side surface and the end surface of the strip, but the unevenness is eliminated by the growing-end mask to form a flat surface. In addition, the end film may be a single film, and 5F may be a multilayer film composed of a plurality of layers with different compositions of A1. Examples of the present invention are shown below. The present invention is not limited to the following examples. Example 1 9 2 (/)) 〇 7Γ 7 二 、

C-plane king plane sapphire substrate 1 is placed in the mocvD reactor, the temperature is 51 n ° r, is & i 0 C uses lice as the carrier gas, ammonia and tmG (trimethylgallium) as raw materials翕, Bu ^ is rm, grow a low-temperature growth buffer layer made of GaN on the supervised gemstone substrate with a film thickness of 200a. "After growing the buffer layer, (υ is doped with Si as the n-type contact layer 3x i 〇i8 / cm3 of GaN with 4, ⑺ as the turtle & p Wanzheng layer will be doped with 渗. 15 μ1 以, (3) as the n-type coating layer will be doped with α ι and ㈣ 25 Α, and an η-type GaN reed with 1 X 1019 / cm3 doped with 5i 丄, W layers, and a layer with a total thickness of 1.2 μΐη superlattice, (4) as a η-type light guide layer As much as possible, make the GaN layer 0.2 μm -19. 200400674 (14) I Description of the invention (5) Barrier layer 100 made of Si doped with inQ G5Ga () 95 ν as the active layer and non-penetrated Quantum well layer with a total film thickness of 38 Å formed by the Ino.iGa (). 9N wellbore layer of 40 A interactive lamination, and the barrier film / well layer / barrier wall layer / well house layer / barrier wall layer (6) As a P-type capping layer, Mg is doped with 1 X 10-20 / cm3 p-type Al. 3GaQ 7N with 300 A '(7) as the P-type light guide layer without doped GaN with 0.2 μm, (8) as the p-type coating layer with un-doped A1G 16GaG 84N with 25 A, and The doped GaN25 A interlayer is a superlattice layer with a total film thickness of 0.6 μΐη. (9) As a P-type contact layer, Mg is doped with lx 102G / cm3 of ρ-type GaN at 150 A and laminated in order. The wafer was annealed in a nitrogen atmosphere in a MOCVD apparatus at 700 ° C to lower the resistance of the p-type nitride semiconductor layer. After annealing, the wafer was taken out of the reaction container 'on the surface of the uppermost P-type contact layer. A strip-shaped protective film (mask) made of SiO2 is formed, and the strip is formed by RIE to expose the end face of the resonator and the surface of the n-type contact layer. The Si02 protective film to be formed on the surface of the p-type contact layer (Mask) is removed with the last name. Next, the wafer is placed in a reaction vessel (high-pressure reactor) in which the system is supercritical ammonia. GaN, which is to be used as feed, 0.5 g, ammonia, 4.7 g, and U 0.036 g as a mineralizer is enclosed in a high-pressure reactor (36 cm3). The temperature in the high-pressure reactor is below 500 ° C ' Orientation temperature region and low temperature region. The wafer is arranged in the high temperature region of 550 ° C, and the GaN and Ga metal are arranged in the low temperature region of 450 ° C. It is placed in the state of the south pressure reactor for 3 days. -20- 200400674 (15) Description of the invention Continuation page With the above, _ Supercritical Kang Sergeant R at low temperature, R phase, lice τ Zhejiang end face film made of early-crystalline GaN with a thickness of 100A It grows on the strip-shaped end surface and side surface, the surface of the exposed n-type contact layer, and the surface of the P-type contact layer. Next, after forming an end film made of single-crystal GaN, single-crystal GaN formed on the p-type contact layer on the uppermost layer is removed by etching, and a stripe-shaped SiC having a width of 1.5 μm is formed on the p-type contact layer ^ The mask is formed into a ridge shape by etching the p-type coating layer on the way. In this etching, the thickness of the P-type cladding layer on the rain side of the ridges after touching was 0.1 μm. A ridge having a width of 1.5 μΐη was formed as described above. Second, a sputtering method is used to form a Zr02 film with a thickness of 0.5 ^ from the top of the SiO 2 mask, such that the Zr02 film is coated on the stripe. After the heat treatment, a filling layer 70 made of a ZrO2 film is formed on the surface of the P-type coating layer on the upper surface of the strip, the side of the ridge, and the rain side of the ridge. The fine ZrO2 film stabilizes the horizontal mode of laser vibration. Next, an electrode 80 made of Ni / Au is formed on the p-type contact layer in ohmic contact, and an n electrode 90 made of Ti / Al is formed on the n-type contact layer. Second, the wafer was heat-treated at 600 ° C. Thereafter, pad electrodes made of Ni (1000 A) _Ti (1000 A) -Au (8000 A) were formed on the ρ and η electrodes, respectively. Then, after forming a reflective film formed of SiO 2 and Ti 〇 2, finally, it is cut from the wafer and divided into individual semiconductor laser devices. : Install a heat sink on the nitride semiconductor laser element obtained above to perform laser vibration. The COD level can be expected to be increased. The limit is 2.0 kA / cm2, 100 mW, and preferably 200 mW. The output power and the continuous vibration time of 405 nm are improved. -21-200400674 (16) I Description of the Invention Continued Example 2 _ Manufactured in Example 1, only at the exit end face of one side of the strip, the end face film made of single crystal GaN will grow with a film thickness of 1 μm, Other points are the same as those of the nitride semiconductor laser device of the embodiment. A heat sink is installed on each of the laser elements obtained as described above, and laser oscillation is performed as in Example 1. The output power and oscillation wavelength with a limit of 2.0 kA / cm2 and 〇〇〇MW can be expected. Continuous vibration of long life at 405 nm. Example 3 In Example 1, after forming a buffer layer on a sapphire substrate, a film thickness of 100 pmGaN was formed by the HVPE method. Thereafter, in the same manner as in Example 1, an n-type nitride semiconductor layer, an active layer, and a p-type nitride semiconductor layer were formed, and the monolithic GaN substrate was removed by removing the solid substrate. The other points were formed in the same manner as in Example 1 to form the end face of the resonator. Thereafter, a single-crystal GaN was formed in supercritical ammonia to a thickness of 100 A to form an end face film. The nitride semiconductor laser device produced can be expected to have the same effect as that of the embodiment i. Example 4 In Example 1, a buffer layer was formed on a sapphire substrate, and then a GaN film having a thickness of 100 μm was formed through the ELO layer by the HVPE method. Thereafter, an n-type nitride semiconductor layer, an active layer, and a p-type nitride semiconductor layer were formed in the same manner as in Example: sapphire substrate was removed to form a nitride semiconductor laser device on a single GaN substrate. Since the aforementioned single GaN substrate is cleaved, the formation surface of the end film can be obtained by cleaving. Thereafter, a single crystal GaN as an end film was formed on the exit end surface in supercritical ammonia with a film thickness of 1 μΐη, and other points were made in the same manner as in Example -22-200400674 Invention Description Continued (17) Example of a nitride semiconductor laser element. The fabricated nitride semiconductor laser device can be expected to have the same effect as that of the first embodiment. Example 5 In Example 1 ', Ag plating was performed on a sapphire substrate. Otherwise, a nitride semiconductor laser device was fabricated in the same manner as in the embodiment. Example 6 A protective film made of Si02 in the form of a lattice pattern was formed on the surface of Example 1 'on the uppermost P-type contact layer, and the resonator end face and the surface of the n-type contact layer were exposed by RIE. Secondly, the aforementioned SiO 2 mask formed on the surface of the p-type contact layer has a state of a film thickness of 0.5 μΐη, and the wafer is arranged in a reactor (high-pressure reactor) with a supercritical gas in the system. Other points are the same as those of the example, and a nitride semiconductor laser device is manufactured. A heat sink is installed on each of the laser elements obtained as described above, and the laser vibration is performed in the same manner as in the embodiment i. It is expected that the output power and the oscillation wavelength of the wheel will be limited to 200 kA / cm2 and 100. Continuous vibration of long life at 405 nm. Example 7 In Example 1, a single-crystal GaN substrate with a substrate thickness of 100 μΏ was used. Further, the end surface forming the end surface of the resonator is cleaved and exposed, and a mask made of SiO2 is formed, and then the end film is grown. Otherwise, a nitride semiconductor laser device was fabricated in the same manner as in the embodiment. Each of the laser elements obtained as described above is equipped with a heat sink to perform laser vibration, which is the same as in Example 1. It is expected that the output power at a limit of 200 kA / cm2, 100 mW, and the vibration wavelength are 405. The longevity of nm continuously vibrates. > 23- 200400674 (18) Industrial application possibility As explained above, the nitride semiconductor of the present invention is between the n-type nitride semiconductor layer and the p-type semiconductor layer, and contains a nitride semiconductor containing In. The formed active layer body laser element forms a single-crystal AlxGai_xN (0 $ film) formed at a low temperature on the resonance radiation end face opposite to the aforementioned laser element, which does not give damage to the aforementioned semi-layer containing nitride containing In. Enlarge the energy gap of the exit end face. Therefore, heteroabsorption can improve the COD level. In this way, according to the present invention, a nitrided object with an output life of 100 mW or more is provided. The end face of the nitride semiconductor at least out of the life of the conductor 1) The end face formed by the light on the end face can provide a high reliability semiconductor laser element -24-

Claims (1)

200400674 Patent application scope 1. A nitride semiconductor laser device having a resonator between an n-type nitride semiconductor layer and a p-type semiconductor layer, which contains an active layer formed of a nitride semiconductor containing In The nitride semiconductor laser device is characterized in that it comprises an end film formed of at least the emission end face of the resonator end face opposite to the above-mentioned laser element, the single-crystal SXS 1) having a larger energy gap than the active layer. It is formed by imparting damage to the aforementioned In-containing nitride semiconductor active layer at a low temperature. 2. For the nitride semiconductor laser device according to item 1 of the patent application scope, wherein the thickness of the end face film is 50 or more and 1 or less. 3. The nitride semiconductor laser device according to item 1 of the application, wherein an end face film made of single crystal AlxGa ^ N ^^ X S 1) is formed in supercritical ammonia on the resonator end face. 4. For a nitride semiconductor laser device according to item 3 of the patent application, wherein at least the p-type contact layer of the aforementioned resonator is masked and a single crystal AlxGahN ^ S 1) is formed on the end face of the aforementioned resonator in supercritical ammonia. Into the end film. 5. The nitride semiconductor laser device as claimed in claim 3, wherein the aforementioned end film contains at least one Group I (IUPAC. 1989) element. 6. The nitride semiconductor laser device according to item 1 of the patent application scope, wherein the active layer is a quantum well structure containing at least one InGaN well house layer or InAlGaN well house layer. 7. The nitride semiconductor laser device according to any one of claims 1 to 6, wherein the aforementioned nitride semiconductor laser device is formed from a substrate selected from the group consisting of GaN 200400674 patent application, continuation sheet, sapphire substrate, and spinel , A ZnO substrate, a SiC substrate, an ELO growth substrate, and a group of substrates formed by growing a substrate of a nitride semiconductor with unevenness on the surface. 8. The nitride semiconductor laser device according to any one of claims 1 to 7, wherein the aforementioned nitride semiconductor laser device is formed on the C-plane, A-plane, or M-plane of a GaN substrate. 9. The nitride semiconductor laser device according to item 1 of the application, wherein the nitride semiconductor laser device is formed on the C surface of the GaN substrate, and the end film is grown on the M surface or the A surface. 10. For the nitride semiconductor laser device according to item 1 of the application, wherein the aforementioned nitride semiconductor laser device is formed on the A surface of the GaN substrate, the emitting surface of the resonator is the M surface, and the aforementioned end film is formed on the M surface. . 11. For example, the nitride semiconductor laser device according to item 1 of the application, wherein the aforementioned nitride semiconductor laser device is formed on the M surface of a GaN substrate grown in supercritical ammonia, and the resonator emission surface is the A surface. The aforementioned end film is formed on the A surface. 12. A method for manufacturing a nitride semiconductor laser device, comprising a resonator between an n-type nitride semiconductor layer and a p-type semiconductor layer, and containing a nitride of an active layer formed of a nitride semiconductor containing In The method for manufacturing a semiconductor laser element includes the following steps: (1) etching or cleaving the laser element to form an opposite end face of the resonator; and (2) step of opposing the laser element. At least the exit end face of the resonator end face forms an end face film formed of a single crystal 1) formed at a low temperature that does not damage the active layer. 200400674 Continued patent application continuation page 13. For the method for manufacturing a nitride semiconductor laser device according to item 12 of the patent application, wherein the aforementioned end mask is formed in supercritical ammonia in the aforementioned second step. 14. The method for manufacturing a nitride semiconductor laser device according to item 13 of the patent application, wherein in the aforementioned second step, at least the p-type contact layer of the resonator is formed with a solubility equal to or lower than that of the supercritical ammonia to the end film. After masking, the aforementioned end film is formed. 15. The method for manufacturing a nitride semiconductor laser device according to item 14 of the application, wherein the aforementioned mask is selected from the group consisting of silicon oxide, silicon nitride, aluminum nitride, Ion, and crane. 16. For the method of manufacturing a nitride semiconductor laser device according to item 12 of the application, wherein the aforementioned end film is formed in supercritical ammonia at a temperature of 900 ° C or lower, preferably 600 ° C or lower, Crystal formation.