JP4545074B2 - Semiconductor manufacturing method - Google Patents

Description

  The present invention relates to a semiconductor manufacturing method and a semiconductor element used for an optical device such as a semiconductor laser or a light emitting diode.

  In recent years, N-based mixed crystal semiconductor materials containing N as a group V element have attracted attention as new semiconductor materials. For example, Patent Document 1 shows an example of epitaxially growing an N-based mixed crystal semiconductor, which is a lattice-matched material, in order to form a group III-V mixed crystal semiconductor on a Si substrate. According to this technology, a misfit dislocation is generated in a group III-V mixed crystal semiconductor element on a Si substrate by using an N-type mixed crystal semiconductor which is a lattice-matched material as the group III-V mixed crystal semiconductor. It is possible to perform epitaxial growth without any problem, and the possibility of monolithic formation with Si electronic devices has been proposed.

  Patent Document 2 discloses N-type mixed crystal semiconductors such as InGaNAs, AlGaNAs, and GANAS that can be lattice-matched with GaAs, InP, and GaP when the substrate is made of GaAs, InP, or GaP. In other words, in the group III-V semiconductors lattice-matched to the GaAs substrate, there was no material having a band gap energy smaller than that of GaAs. However, for example, InGaNAs can be lattice-matched to the GaAs substrate, and Since the band gap energy is small, it has been found that a light emitting element having an emission wavelength longer than the emission wavelength of GaAs that could not be formed on a conventional GaAs substrate (such as a 1.5 μm band) can be formed.

In such an N-based group V mixed crystal semiconductor, group V atoms such as As are easily desorbed from the substrate surface even at low temperatures, so low temperature growth is desirable. However, NH ₃ or the like often used as a raw material for N is decomposed only at high temperatures. Therefore, it is not preferable as a raw material for an N-based V group mixed crystal semiconductor containing N and As at the same time. For this reason, in the above-described conventional technique, instead of using NH ₃ as an N raw material as it is, MBE which is high vacuum is generated by using active nitrogen element by high frequency plasma from nitrogen gas or nitrogen compound gas such as NH _3. An N-based group V mixed crystal semiconductor is formed by a low-pressure MOCVD method of about 0.1 Torr. In addition, a report of obtaining a GaNAs mixed crystal by a general low pressure MOCVD method of 60 Torr using DMHy ((CH ₃ ) ₂ NNH ₂ (dimethylhydrazine) which is an organic nitrogen compound as a raw material of N (author “N. There is also a non-patent document 1) by “Ohkouchi” and the like.

However, since N easily separates from the substrate surface during growth, it is difficult to obtain an N-based V group mixed crystal semiconductor having a large N composition. For this reason, conventionally, a film having an N composition required by a growth method focusing on increasing the concentration of N which is difficult to add is formed. In an example in which activated nitrogen gas is used as the N raw material, the growth pressure needs to be lowered in order not to deactivate the active nitrogen. Specifically, when the N-based group V mixed crystal semiconductor is, for example, GaNAs, the As must be grown under a very low partial pressure of As, which is another group V element. ) Increased, and a high-quality N-based V group mixed crystal semiconductor could not be obtained. For example, in Non-Patent Document 2 by the author “M. Sato”, in order to obtain 1% N composition, the conditions are as follows: reaction chamber: 25 Pa, N ₂ flow rate: 50 sccm, AsH ₃ flow rate: 10 sccm. That is, when N ₂ is activated in the high-frequency plasma, the reaction chamber becomes about 300 Pa, but this is adjusted to grow to 25 Pa. However, under this condition, the AsH ₃ partial pressure becomes a low partial pressure of about 0.9 Pa. In addition to this, since it is necessary to supply TEG (triethylgallium), which is a Group III raw material, and H ₂ as a carrier gas, the actual AsH ₃ partial pressure is lower. Further, in order to further increase the N composition, it is necessary to further reduce the pressure, increase the N raw material, and decrease the AsH ₃ flow rate, and the AsH ₃ partial pressure is further reduced. For this reason, in the conventional method, the As (V group) vacancy concentration is increased, and when the N concentration is increased, it becomes metal rich (group III rich), and a high quality N-based V group mixed crystal semiconductor is obtained. I could not.

Further, even in a report by a general low pressure MOCVD method of 60 Torr using DMHy ((CH ₃ ) ₂ NNH ₂ (dimethylhydrazine) which is an organic nitrogen compound as a raw material of N, the composition of N is about 0.5% or less. That is, even in this method, the DMHy flow rate is increased, the GaNAs layer is formed under the condition of a small AsH ₃ flow rate, and the growth is performed under the condition of a low AsH ₃ partial pressure. For this reason, when trying to increase the N composition, it becomes metal rich due to loss of As, and there is a problem that a mixed crystal having a large N composition cannot be obtained even if the N raw material flow rate is increased.
Japanese Patent Laid-Open No. 06-334168 Japanese Patent Laid-Open No. 06-037355 “MOVPE Growth of GaAs1-xNxAlloys”, 12th Symposium on Alloy Semiconductor Physics and Electronics p337 ~ 340 “Plasma-assisted MOCVD grouth of GaAsallows”, 13th Symposium on Alloy Semiconductor Physics and Electronics P101 ～ 102

  SUMMARY OF THE INVENTION An object of the present invention is to provide a semiconductor manufacturing method and a semiconductor device capable of forming a high N-group III-V mixed crystal semiconductor having a high N composition without increasing the group V vacancy concentration. It is said.

In order to achieve the above object, according to the first aspect of the present invention, at least one group III-V mixed crystal semiconductor layer comprising a plurality of group V elements simultaneously containing N and As is formed on a predetermined semiconductor substrate under reduced pressure conditions. In the method for producing a semiconductor formed at a temperature of 550 ° C. or higher , the N composition of the organic nitrogen compound as a raw material of N in the group V element of the group III-V mixed crystal semiconductor layer is 0.5% or more. And using AsH3 as the As raw material, the partial pressure of the As raw material in the reactor is 2 Pa or more.

As described above, according to the invention of claim 1 Symbol placement, can produce a large N III-V group mixed crystal epitaxial wafer having the composition of high quality without increasing the vacancy concentration V group, further these By using a high-quality N-system V group mixed crystal semiconductor, a high-performance light-emitting device and light-receiving device having a new structure can be manufactured. Therefore, for example, it is possible to form a light-emitting element having excellent temperature characteristics and a high output as compared with an InGaAsP-based element that is a general material system in a long wavelength band. This makes it possible to apply to low-cost communication lasers that do not use an APC (auto power control) circuit or an electronic cooler, eye-safe lasers for distance measurement, eye-safe lasers for spatial transmission, and the like. Further, if it is formed on a Si substrate, it becomes possible to make the Si electronic element and the Si substrate lattice matching compound semiconductor element monolithic.

  Hereinafter, the best mode for carrying out the present invention will be described. FIG. 1 is a diagram showing a configuration example of an MOCVD apparatus for manufacturing a semiconductor according to the present invention. The MOCVD apparatus in FIG. 1 is a horizontal furnace apparatus having a general configuration, and FIG. 1 shows a reaction chamber portion. Of course, the MOCVD apparatus may be a vertical furnace.

  Referring to FIG. 1, this apparatus includes a water-cooled quartz reaction tube 12 whose inside functions as a reaction furnace, a gas supply port 11 for supplying a source gas and a carrier gas into the quartz reaction tube 12, and a semiconductor of the present invention. A carbon susceptor 14 that holds the substrate 25 on which the substrate is grown, a high-frequency heating coil 13 that heats the carbon susceptor 14 (substrate 25), a thermocouple 15 that measures the temperature of the carbon susceptor 14 (substrate 25), And an exhaust device 16 for exhausting the inside of the quartz reaction tube 12 (inside the reaction furnace).

  The semiconductor of the present invention can be manufactured by MOCVD (metal organic chemical vapor deposition) using such an MOCVD apparatus.

That is, in the first embodiment of the present invention, when forming at least one group III-V mixed crystal semiconductor layer composed of a plurality of group V elements simultaneously containing N and As on a predetermined semiconductor substrate, The group V mixed crystal semiconductor layer is made of an organic nitrogen compound as an N raw material, AsH ₃ is used as an As raw material, the AsH ₃ partial pressure in the reactor is 2 Pa or higher, and the substrate temperature during growth is 550 ° C. or higher. As described above, crystals are grown by metal organic chemical vapor deposition (MOCVD).

In the second embodiment of the present invention, when forming at least one group III-V mixed crystal semiconductor layer made of a plurality of group V elements containing N and As simultaneously on a predetermined semiconductor substrate, The group V mixed crystal semiconductor layer is made of an organic nitrogen compound as an N raw material, AsH ₃ is used as an As raw material, the AsH ₃ partial pressure in the reactor is 10 Pa or higher, and the substrate temperature during growth is 600 ° C. or higher. As described above, crystals are grown by metal organic chemical vapor deposition (MOCVD).

In the first and second embodiments, NH ₃ is often used as a nitrogen source for nitrogen-based III-V semiconductors by MOCVD. However, NH ₃ has low decomposition efficiency. Since N and other group V elements (As, etc.) are easily separated from the surface at a high temperature, it is desirable to perform nitrogen-based group V mixed crystal semiconductor growth such as an InGaNAs layer at a low temperature. From this point of view, NH ₃ is not suitable. . As a raw material of N, an organic nitrogen compound raw material that is easily decomposed at a low temperature is desirable. Therefore, in the present invention, an organic nitrogen compound raw material such as DMHy ((CH ₃ ) ₂ NNH ₂ : dimethylhydrazine) or TBA ((CH ₃ ) ₃ CNH ₂ : tertiarybutylamine) is used. Here, DMHy and TBA have a high vapor pressure, and the flow rate of the carrier gas (H ₂ ) for bubbling can be reduced. For this reason, the supply amount variation due to the temperature variation of the cylinder is reduced, and it is desirable because there is an advantage that a high quality N-based V group mixed crystal semiconductor can be obtained with good uniformity.

In the present invention, for example, an InGaNAs layer can be formed with a high quality as a III-V group mixed crystal semiconductor layer on a GaAs substrate as a semiconductor substrate. That is, when In is added to GaAs, the lattice constant increases and the band gap energy decreases. On the other hand, when N is added, the lattice constant is reduced, and the band gap energy is similarly reduced. That is, when N is added to In _x Ga _1-x As, the band gap energy becomes smaller than In _x Ga _1-x As, and there is a condition that the lattice constant coincides with GaAs. As described above, since the InGaNAs layer can be lattice-matched to the GaAs substrate, a light-emitting element having a longer wavelength than the light emission wavelength of about 870 nm (room temperature) corresponding to the band gap energy of GaAs is used as an InGaAs having a larger lattice constant than GaAs. Compared to the conventional case where the is used for the light emitting layer, it can be easily formed with high quality. In addition, it is possible to form longer-wavelength elements, such as 1.3 μm band and 1.5 μm band, as compared with the conventional case.

  Further, in the present invention, when forming at least one group III-V mixed crystal semiconductor layer made of a plurality of group V elements including N on a predetermined semiconductor substrate, an impurity for controlling the conductivity type and the carrier concentration. As described above, Se is used for the n-type, and Group II elements such as Zn and Mg are used for the p-type.

  Moreover, as described above, a high-quality, high-performance semiconductor laser or light-emitting diode can be obtained by using a group III-V mixed crystal semiconductor formed by the above manufacturing method in at least the light-emitting layer.

  Examples of the present invention will be described below.

In Example 1, the above-described InGaNAs were grown on a GaAs substrate using the MOCVD apparatus shown in FIG. That is, TMG (trimethyl gallium) or TEG (triethyl gallium), TMI (trimethyl indium) or TEI (triethyl indium) is used as the group III material, AsH ₃ (arsine) is used as the As material, and N DMHy (dimethylhydrazine) or MMHy (monomethylhydrazine) or TBA (tertiarybutylamine), which is an organic nitrogen compound, is used as a raw material, and these raw material gases are water-cooled from the gas supply port 11 simultaneously with the carrier gas H _2. Into the quartz reaction tube 12 of the formula. At this time, the reaction chamber was evacuated to 1.3 × 10 ⁴ Pa by the exhaust device 16. Further, the carbon susceptor 14 was heated by the high frequency heating coil 13 to heat the GaAs substrate as the growth substrate 15. Thus, the source gas was pyrolyzed, and a predetermined element of the pyrolyzed source gas was grown on the GaAs substrate by a substrate surface reaction. In Example 1, TMG: 4.0 × 10 ⁻⁶ mol / min to 4.0 × 10 ⁻⁵ mol / min, TMI: 4.4 × 10 ⁻⁷ mol / min to 4.4 × 10 ⁻⁶ mol / min, AsH ₃ : 6.0 × 10 ⁻³ mol / min (0.4 sccm) to 2.2 × 10 ⁻³ mol / min (46.4 sccm), DMHy: 5.0 × 10 ⁻⁴ Mol / min to 3.0 × 10 ⁻² mol / min, H ₂ as a carrier gas is added, and the raw material gas and the carrier gas are combined to supply a total of 6 (l / min). Further, the AsH ₃ partial pressure was set to 0.9 to 102 Pa, and the growth temperature was set to 450 to 700 ° C.

Actually, TMG: 2.0 × 10 ⁻⁵ mol / min, TMI: 2.2 × 10 ⁻⁶ mol / min, AsH ₃ : 3.3 × 10 ⁻⁴ mol / min (7 sccm), DMHy: 6.4 At × 10 ^-3 mol / min, the AsH ₃ partial pressure was 15.4 Pa. In this case, the AsH ₃ partial pressure is higher than the conventional one, but the DMHy supply amount is further increased by about one digit than the AsH ₃ supply amount. The growth temperature was 630 ° C. The growth rate was 1.7 μm / h. FIG. 2 shows the SIMS analysis result of the InGaNAs layer manufactured under such conditions. The N concentration was determined to be about 6.5 × 10 ²⁰ atoms / cm ³ . This corresponds to an N composition of about 3%. From the lattice constant of the InGaNAs layer obtained by the X-ray diffraction method using Cu—Kα ray based on this value, the In composition was determined to be about 6%. From this result, it was found that an In _0.06 Ga _0.94 N _0.03 As _0.97 layer was formed. This InGaNAs layer had a smaller lattice constant than the GaAs substrate. Further, PL (photoluminescence) measurement was performed at room temperature using an Ar laser (488 nm) as an excitation light source and a Ge-photodiode as a light receiver. As a result, the center wavelength was about 1.2 μm.

Also, FIG. 3 shows the room temperature of the InGaNAs layer when the InGaNAs layer (In composition: 6%) is prepared by changing the conditions in the range where the AsH ₃ partial pressure is 4.8 Pa or more (by changing the N composition). PL characteristics are shown. FIG. 3 shows that the center wavelength shifts to the longer wavelength side as the N composition increases. The center wavelength was about 1.15 μm at a film thickness of 2.1% N composition lattice matched to the GaAs substrate.

Further, in the experiment by the inventors of the present application, under the same gas supply rate, the N composition increased as the growth temperature decreased. When the N raw material supply amount and the growth temperature were the same, the N composition increased as the AsH ₃ partial pressure decreased. In order to obtain the same N composition under a constant AsH ₃ partial pressure, it is necessary to increase the supply amount of DMHy, which is a raw material of N, as the temperature grows higher.

It was also found that an InGaN _y As _ly layer having a large N composition (y) that does not become metal rich (group III rich) can be obtained as the AsH ₃ partial pressure is increased even at a relatively high temperature growth of 600 ° C. or higher. FIG. 4 shows the condition dependency of the N composition of the mixed crystal (In _0.13 Ga _0.87 N _y As _1-y ) that can be formed. For example, when grown at 600 ° C. and the AsH ₃ partial pressure is 2 Pa, the N composition was about 1% at maximum, but at 10 Pa, a 4.6% InGaNAs layer was obtained. Further, even when the AsH ₃ partial pressure is as low as 2 Pa or less, it is possible to increase the N composition because the As escape is suppressed and the N desorption is also suppressed by performing low temperature growth at about 450 to 550 ° C., for example. It was. However, at such a low growth temperature, the PL intensity was very weak. It was effective to set the growth temperature to 550 ° C. or higher. Therefore, the substrate temperature during growth is desirably 550 ° C. or higher. Furthermore, the PL intensity became almost constant at 600 ° C. or higher. Further, the same growth temperature, the same composition, according to the PL properties of the film obtained in experiments with different AsH ₃ partial pressure, the higher AsH ₃ partial pressure PL intensity tended to be higher quality. FIG. 5 shows the relationship between the PL temperature and the growth temperature of the In _0.06 Ga _0.94 N _0.02 As _0.98 layer and the AsH ₃ partial pressure. Although low temperature growth is effective for increasing the N composition, it has been found that it is better not to make the temperature too low because the PL intensity decreases.

As described above, according to the results of experiments by the inventors of the present application, when the AsH ₃ partial pressure is lower than 2 Pa, an InGaN _y As _1-y layer having an N composition of 2% or more showing good PL characteristics cannot be obtained. . If the AsH ₃ partial pressure is low, As escape is promoted and the metal is likely to be rich, and it can be considered that it cannot be formed unless the temperature is 550 ° C. or lower. In other words, when the N raw material flow rate is increased and the AsH ₃ flow rate is reduced to grow at a low temperature, an InGaN _y As _1-y layer having a high N composition tends to be obtained. However, if the AsH ₃ partial pressure is reduced too much, a good crystal is obtained. I found out I couldn't get it. By setting the AsH ₃ partial pressure to 2 Pa or higher and the growth temperature to 550 ° C. or higher, a mixed crystal having an N composition of 2% or higher with high PL strength and good crystallinity was obtained. With an N composition of 2%, InGaAs with an In composition of about 6% can be lattice-matched to the GaAs substrate. This N composition of 2% is an N composition sufficient to form a solid-state laser excitation semiconductor laser with a wavelength of about 980 nm. Further, when the AsH ₃ partial pressure is 10 Pa or higher, a mixed crystal having an N composition of 4% or higher can be formed even at a relatively high temperature growth of 600 ° C. or higher, and high-quality InGaN _y As _{1-y having a} high PL strength. It was found that a layer was obtained. When the N composition is 4.6%, InGaAs having an In composition of about 13% can be lattice-matched to the GaAs substrate, and a semiconductor laser having a wavelength longer than 1.3 μm used mainly for communication can be formed.

In _0.08 Ga _0.92 in which an N composition of 4.6% was obtained by an X-ray diffraction method (θ-2θ measurement) using Cu—Kα rays (wavelengths: Kα1 = 0.15405 nm, Kα2 = 0.15444 nm). The result of analyzing the NAs layer is shown in FIG. Here, the thickness of the InGaNAs layer was 0.5 μm. FIG. 6 shows that the In _0.08 Ga _0.92 NAs layer has a smaller lattice constant than GaAs. Further, according to Nomarski observation, no cross-hatch pattern due to lattice relaxation was observed on the surface, and it was a mirror surface like the GaAs layer on the GaAs substrate.

As described above, an organic nitrogen compound material that is easily decomposed at a low temperature is used as a raw material for N, and an organic material using a conventional organic nitrogen compound material is grown by performing growth at a high AsH ₃ partial pressure (at least 2 Pa or more). An N-based V group mixed crystal semiconductor in which the ratio (composition) of N in the group V element, which was the limit by the metal vapor deposition method, was 0.5% or more could be easily formed. In addition, since the growth was carried out at a high growth temperature (at least 550 ° C. or higher), a high-quality N-based group V mixed crystal semiconductor with high PL emission efficiency could be formed. Furthermore, when the AsH ₃ partial pressure was 10 Pa or more and the growth temperature was 600 ° C. or more, InGaNAs having an N composition of 4% or more could be formed with high quality.

  Note that the InGaNAs layer may not be perfectly lattice-matched to the GaAs substrate, and may have a thickness within the critical thickness even if it has a strain. In this embodiment, the case of InGaNAs as the N-based group V mixed crystal semiconductor has been described. However, the manufacturing method can be applied to other mixed crystals such as GaNAs, AlNAs, InAlNAs, AlGaNAs, InAlGaNAs, and InGaNAsP.

In Example 2, a light emitting element having an InGaNAs layer as a light emitting layer was manufactured. 7 is a cross-sectional view of the light emitting device of Example 2. FIG. Referring to FIG. 7, the light emitting device includes an n-type Al _0.4 Ga _0.6 As clad layer 42, an InGaNAs active layer 43, a p-type Al _0.4 Ga _0.6 As clad layer 44, and a p-type GaAs contact on an n-type GaAs substrate 41. The layers 45 are sequentially formed by MOCVD, a p-side electrode 46 is formed on the p-type GaAs contact layer 45, and an n-side electrode 47 is formed on the back surface of the n-type GaAs substrate 41. This device structure is a broad stripe type.

Here, the growth conditions of the InGaNAs active layer are controlled to the composition lattice-matched with GaAs using the conditions shown in the first embodiment. Note that the InGaNAs layer may not be perfectly lattice-matched to the GaAs substrate, and may have a thickness within the critical thickness even if it has a strain. The AsH ₃ partial pressure was 25 Pa, which was higher than the conventional one. As a result, an InGaNAs active layer having a high luminous efficiency with a lower group V vacancy concentration than the conventional one was obtained.

Further, the InGaNAs layer has a smaller band gap energy than GaAs, and the confinement of carriers in the active layer is good. As a result, a light-emitting element having excellent temperature characteristics and high output as compared with an InGaAsP element which is a general material system in a long wavelength band can be formed. In this embodiment, Al _0.4 Ga _0.6 As is used as the cladding layer, but AlGaAs of other compositions may be used. In this embodiment, the layer structure is described as a simple DH (double hetero) structure, but the present invention can be applied to other structures such as a quantum well structure. In addition, the device structure can be various structures other than the broad stripe type. Although the active layer has been described as being InGaNAs, any material can be used as long as it is a mixed crystal containing Al and P as long as it is a mixed crystal containing N and As simultaneously.

  In addition, according to this embodiment, a light-emitting element having excellent temperature characteristics and a high output can be formed as compared with an InGaAsP-based element that is a general material system in a long wavelength band. Therefore, the present invention can be applied to low-cost communication lasers that do not use an APC (auto power control) circuit or an electronic cooler, an eye-safe laser for distance measurement, an eye-safe laser for spatial transmission, and the like.

  In Example 2, an example of a light emitting element having a double hetero structure in which an InGaNAs layer is used as a light emitting layer is shown. However, a homojunction or single heterojunction light emitting element in which an InGaNAs layer is used as a light emitting layer can also be configured. FIG. 8 is a cross-sectional view of the light emitting device of Example 3. Referring to FIG. 8, this light-emitting element is a homojunction light-emitting element, and an n-type InGaNAs layer 72, a p-type InGaNAs layer 73, and a p-type GaAs contact layer 74 are sequentially formed on an n-type GaAs substrate 71 by MOCVD. The p-side electrode 75 is formed on the p-type GaAs contact layer 74, and the n-side electrode 76 is formed on the back surface of the n-type GaAs substrate 71.

Here, the growth conditions of the InGaNAs layer are basically the conditions shown in Example 1 and controlled to a composition that lattice matches with GaAs. Further, the AsH ₃ partial pressure was 50 Pa, which was higher than before. As a result, an InGaNAs active layer having a high luminous efficiency with a lower group V vacancy concentration than the conventional one was obtained.

In addition, it was possible to use Se for n-type and Zn for p-type for controlling the conductivity type and carrier concentration. That is, in FIG. 8, Se or the like can be used for the n-type impurity of the n-type InGaNAs layer 72, and Zn or the like can be used for the p-type impurity of the p-type InGaNAs layer 73. Here, H ₂ Se (hydrogen selenide) could be used as the Se raw material, and DMZn (dimethyl zinc) or DEZn (diethyl zinc) could be used as the Zn raw material. In this case, the doping efficiency was high.

  That is, in the double heterostructure light emitting device shown in Example 1 and Example 2, when this is a double heterostructure laser, the InGaNAs active layer is usually undoped, and the impurity control is Although not required (however, even in a double hetero structure, in the case of an LED (light emitting diode), the active layer is often doped with impurities, in which case impurity control is required), but the homojunction structure shown in Example 3 In this light emitting element (LED), it is necessary to control n-type and p-type impurities (control of conductivity type and carrier concentration). In this Example 3, Se or the like is used as the n-type impurity, and p Zn or the like could be used as the type impurity.

The InGaNAs layer has a smaller band gap energy than GaAs, and the light emitted from the InGaNAs layer is transparent to the GaAs contact layer. For this reason, the light-emitting elements of Example 2 and Example 3 are particularly advantageous in a surface-emitting light-emitting element. Of course, Sn, C, Si, Mg, etc. can be used as impurities in addition to Se and Zn. However, group IV elements such as Si and C are amphoteric impurities and may enter and compensate for group III and group V sites. However, Se and Zn are group VI and group II elements, respectively. In addition, since the above situation does not occur, it is preferable to use Se and Zn as impurities. Further, a pn junction may be formed by diffusion of impurities such as Zn. Moreover, although the active layer is InGaNAs, even if it is a mixed crystal containing Al or P, it may be a mixed crystal containing N and As at the same time.

It is a figure which shows the structural example of the MOCVD apparatus for manufacturing the semiconductor which concerns on this invention. It is a figure which shows the SIMS analysis result of an InGaNAs layer. It is a figure which shows the room temperature PL characteristic of an InGaNAs layer. Is a diagram showing a condition dependence of N composition of the film formation can be mixed _{(In 0.13 Ga 0.87 N y As} 1-y). In _0.06 Ga _0.94 N _0.02 As _0.98 layers growth temperature is a diagram showing the relationship of PL intensity for AsH ₃ partial pressure. In _0.08 Ga _0.92 NAs layer in which 4.6% of N composition was obtained by X-ray diffraction method (θ-2θ measurement) using Cu—Kα rays (wavelength: Kα1 = 0.15405 nm, Kα2 = 0.15444 nm) It is a figure which shows the result of having analyzed. 6 is a cross-sectional view of a light-emitting element according to Example 2. FIG. 6 is a cross-sectional view of a light-emitting element according to Example 3. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Gas supply port 12 Quartz reaction tube 13 High frequency heating coil 14 Carbon susceptor 15 Thermocouple 16 Exhaust device 41 n-type GaAs substrate 42 n-type Al _0.4 Ga _0.6 As cladding layer 43 InGaNAs active layer 44 p-type Al _0.4 Ga _0.6 As cladding Layer 45 p-type GaAs contact layer 46 p-side electrode 47 n-side electrode 71 n-type GaAs substrate 72 n-type InGaNAs layer 73 p-type InGaNAs layer 74 p-type GaAs contact layer 75 p-side electrode 76 n-side electrode

Claims (1)

In a semiconductor manufacturing method, at least one group III-V mixed crystal semiconductor layer composed of a plurality of group V elements simultaneously containing N and As is formed on a predetermined semiconductor substrate under reduced pressure conditions and a temperature of 550 ° C. or higher . , Supplying an organic nitrogen compound as a raw material of N so that an N composition in the group V element of the III-V mixed crystal semiconductor layer is 0.5% or more, and using AsH3 as a raw material of As, A method for producing a semiconductor, characterized in that a partial pressure of an As raw material in a reaction furnace is 2 Pa or more.

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