JPH01243514A - Formation of semiconductor crystal layer - Google Patents
Formation of semiconductor crystal layerInfo
- Publication number
- JPH01243514A JPH01243514A JP6963988A JP6963988A JPH01243514A JP H01243514 A JPH01243514 A JP H01243514A JP 6963988 A JP6963988 A JP 6963988A JP 6963988 A JP6963988 A JP 6963988A JP H01243514 A JPH01243514 A JP H01243514A
- Authority
- JP
- Japan
- Prior art keywords
- crystal layer
- substrate
- semiconductor crystal
- light
- gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000013078 crystal Substances 0.000 title claims abstract description 40
- 239000004065 semiconductor Substances 0.000 title claims abstract description 22
- 230000015572 biosynthetic process Effects 0.000 title description 5
- 239000000758 substrate Substances 0.000 claims abstract description 26
- 238000000034 method Methods 0.000 claims description 8
- 238000001947 vapour-phase growth Methods 0.000 claims description 4
- 230000001678 irradiating effect Effects 0.000 abstract description 12
- 229910001218 Gallium arsenide Inorganic materials 0.000 abstract description 10
- 239000000463 material Substances 0.000 abstract description 4
- 239000012535 impurity Substances 0.000 abstract description 3
- 238000006557 surface reaction Methods 0.000 abstract description 3
- 238000000354 decomposition reaction Methods 0.000 abstract description 2
- 238000009792 diffusion process Methods 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 28
- 239000002994 raw material Substances 0.000 description 14
- 239000012071 phase Substances 0.000 description 6
- RBFQJDQYXXHULB-UHFFFAOYSA-N arsane Chemical compound [AsH3] RBFQJDQYXXHULB-UHFFFAOYSA-N 0.000 description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 239000012159 carrier gas Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 239000003085 diluting agent Substances 0.000 description 2
- 238000010574 gas phase reaction Methods 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 238000002488 metal-organic chemical vapour deposition Methods 0.000 description 2
- 150000002902 organometallic compounds Chemical class 0.000 description 2
- 238000010926 purge Methods 0.000 description 2
- HTDIUWINAKAPER-UHFFFAOYSA-N trimethylarsine Chemical compound C[As](C)C HTDIUWINAKAPER-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- YZCKVEUIGOORGS-OUBTZVSYSA-N Deuterium Chemical compound [2H] YZCKVEUIGOORGS-OUBTZVSYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000000862 absorption spectrum Methods 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 229910052805 deuterium Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 150000004678 hydrides Chemical class 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- VSQYNPJPULBZKU-UHFFFAOYSA-N mercury xenon Chemical compound [Xe].[Hg] VSQYNPJPULBZKU-UHFFFAOYSA-N 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 125000002524 organometallic group Chemical group 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- RGGPNXQUMRMPRA-UHFFFAOYSA-N triethylgallium Chemical compound CC[Ga](CC)CC RGGPNXQUMRMPRA-UHFFFAOYSA-N 0.000 description 1
- XCZXGTMEAKBVPV-UHFFFAOYSA-N trimethylgallium Chemical compound C[Ga](C)C XCZXGTMEAKBVPV-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔発明の目的〕
（産業上の利用分野）
本発明は、気相成長法による半導体結晶層の形成方法に
関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method for forming a semiconductor crystal layer by vapor phase growth.
（従来の技術）
近年、半導体素子の高性能化、高機能化にともない、原
子層精度で結晶層を積層した精密で複雑な構造の作り込
みが必要とされている。従来のＭＯＣＶＤ法等の気相成
長法においては、基板を置いた容器内に原料ガスを導入
し、基板を高温に加熱して原料ガスを熱分解することに
よって半導体結晶層を成長させていた。しかしながら、
基板温度が高いと、構成元素の拡散により界面の急峻性
が劣化し、作υ込んだ構造を維持できなくなる。(Prior Art) In recent years, as semiconductor devices have become higher in performance and functionality, it has become necessary to create precise and complex structures in which crystal layers are laminated with atomic layer accuracy. In conventional vapor phase growth methods such as MOCVD, a semiconductor crystal layer is grown by introducing a raw material gas into a container in which a substrate is placed, heating the substrate to a high temperature, and thermally decomposing the raw material gas. however,
When the substrate temperature is high, the steepness of the interface deteriorates due to diffusion of constituent elements, making it impossible to maintain the created structure.
このため、基板温度を下げることが不可決となっている
。For this reason, it has become unreliable to lower the substrate temperature.
従来の形成方法のままで基板温度を下げると、原料ガス
が十分に分解されず、成長速度が著しく小さくなった。When the substrate temperature was lowered using the conventional formation method, the source gas was not sufficiently decomposed and the growth rate was significantly reduced.
さらに、未分解の原料ガスが不純物として結晶層中に取
シ込まれ、あるいは、表面反応種の表面拡散が十分でな
いために結晶性が悪化し、電気的、光学的に十分な特性
の半導体結晶層が得られないという問題があった。Furthermore, undecomposed raw material gases may be introduced into the crystal layer as impurities, or surface reactive species may not diffuse sufficiently on the surface, resulting in deterioration of crystallinity, resulting in a semiconductor crystal with sufficient electrical and optical properties. There was a problem that layers could not be obtained.
この問題を解決するために、気相の原料ガスが吸収する
波長の光を照射しながら半導体結晶層の形成を行った。In order to solve this problem, a semiconductor crystal layer was formed while irradiating light with a wavelength that is absorbed by the gaseous source gas.
しかし、結晶層の成長速度は著しく増大したものの、形
成した結晶層の品質の向上は不十分であった。However, although the growth rate of the crystal layer was significantly increased, the quality of the formed crystal layer was not sufficiently improved.
（発明が解決しようとする課題）
以上のように、従来の半導体結晶層の形成方法において
は、精密な構造を作り込むために基板温度を下げると、
良質な半導体結晶層が得られなかった。本発明は、この
問題を解決し、低温で良質の半導体結晶を成長すること
を可能にした半導体結晶層の形成方法を提供することを
目的とする。(Problem to be Solved by the Invention) As described above, in the conventional method of forming a semiconductor crystal layer, when the substrate temperature is lowered in order to create a precise structure,
A good quality semiconductor crystal layer could not be obtained. An object of the present invention is to provide a method for forming a semiconductor crystal layer that solves this problem and makes it possible to grow high-quality semiconductor crystals at low temperatures.
（課題を解決するだめの手段）
本発明は、原料ガスを導入し、気相成長法により半導体
結晶層を成長させる際に、基板に吸着した原料ガスの吸
収する波長の光を照射することを特徴とする。(Means for Solving the Problems) The present invention provides a method of irradiating light with a wavelength that is absorbed by the source gas adsorbed on the substrate when introducing a source gas and growing a semiconductor crystal layer by vapor phase growth. Features.
（作 用）
基板表面に吸着した原料ガスの吸収スペクトルは、気相
のものと大きく異なる。気相ではなく、表面に吸着した
原料ガスの吸収する波長の光を照射することによシ、表
面に未分解で到達した原料ガスの分解を促すと共に、表
面反応を励起することによシ、結晶中への不純物の取り
込みを抑え、高品質の半導体結晶を得ることができる。(Function) The absorption spectrum of the source gas adsorbed on the substrate surface is significantly different from that of the gas phase. By irradiating light with a wavelength that is absorbed by the raw material gas adsorbed on the surface rather than in the gas phase, it promotes the decomposition of the raw material gas that has reached the surface undecomposed, and also stimulates surface reactions. It is possible to suppress the incorporation of impurities into the crystal and obtain a high quality semiconductor crystal.
また、気相での吸収が比較的小さい場合には、気相を通
過する際にあまシ減衰せずに基板に照射することができ
、効率よく表面反応を励起することができる。さらに、
気相の原料ガスの吸収する波長の光を併せて照射するこ
とで、気相反応と表面での反応を独立に励起、制御する
ことができ、高品質の半導体結晶層を形成することがで
きる。Further, when the absorption in the gas phase is relatively small, the substrate can be irradiated without being attenuated while passing through the gas phase, and surface reactions can be efficiently excited. moreover,
By irradiating the material with light at a wavelength that is absorbed by the gas-phase raw material gas, it is possible to independently excite and control the gas-phase reaction and the reaction on the surface, making it possible to form a high-quality semiconductor crystal layer. .
（実施例）
以下、本発明の実施例としてＧａＡｓ結晶層を形成した
例を図面を参照して説明する。(Example) Hereinafter, an example in which a GaAs crystal layer is formed as an example of the present invention will be described with reference to the drawings.
第１図は本発明を実施した結晶層の成長装置である。FIG. 1 shows a crystal layer growth apparatus in which the present invention is implemented.
″成長容器１には基板２がサセプタ３上にａ置されて収
容されている。サセプタ３がヒータ４によシ加熱されて
、基板２は所定温度に設定されている。成長容器１には
ガス導入口５より■族原料である有機金属化合物及びＶ
族原料である水素化物がキャリアガス、希釈ガスと共に
導入される。また、成長容器ｌ内の基板２には、２台の
エキシマレーザ６．７から出射されたレーザ光８．９が
、誘電体多層反射ミラー１０．１１．及び、合成石英製
あるいはＭ ｇ ｋ’ ２製の光導入窓１２．１３を介
して照射される。ガス導入口１４．１５からは、光導入
窓１２．１３への膜付着を抑制するために光に対して透
明なパージガスが導入されるようになっている。ガス導
入口５，１４．１５から成長容器ｌに導入されたガスを
排気する排気系１６の排気速度を調整することにより、
成長容器ｌ内の圧力は所定値に設定されている。``A substrate 2 is housed in the growth container 1, placed a on a susceptor 3.The susceptor 3 is heated by a heater 4, and the substrate 2 is set at a predetermined temperature. From the gas inlet 5, the organometallic compound, which is a group III raw material, and V
A hydride, which is a group raw material, is introduced together with a carrier gas and a diluent gas. Further, the laser beams 8.9 emitted from the two excimer lasers 6.7 are applied to the substrate 2 in the growth chamber l, and the dielectric multilayer reflection mirrors 10.11. The light is then irradiated through a light introduction window 12.13 made of synthetic quartz or M g k' 2. A purge gas transparent to light is introduced from the gas inlet 14.15 in order to suppress film adhesion to the light introduction window 12.13. By adjusting the exhaust speed of the exhaust system 16 that exhausts the gas introduced into the growth container l from the gas inlet 5, 14.15,
The pressure inside the growth container 1 is set to a predetermined value.
次に、この様な成長装置を用いて行ったＧａＡｓ結晶層
のＭＯＣＶＤエピタキシャル成長について具体的に説明
する。基板にはＣｒＯドープ半絶縁性Ｇ ａ Ａ Ｓウ
ェハをもちいた。■族原料としてトリメチルガリウム（
ＴＭＧ）を、Ｖ族原料としてアルシンを、■族原料のキ
ャリアガス、希釈ガス、パージガスとして水素を用いた
。ＴＭＧ、アルシンの供給量はＱ、 ５ ＳＣＣｍ 、
５ Ｑ ＳＣＣｍ 、全水素の流量は５００ ｓｃ
Ｃｍで、圧力ｆ １０ Ｔｏｒｒと設定した。従来の方
法でＧａＡｓ結晶層を形成する場合には、基板温度を７
００℃程度に設定するが、本実施例においては、基板温
度を４００℃に設定゛した。結晶層の成長中、エキシマ
レーザ６からは、ＴＭＧ、アルシンによって気相で強く
吸収される人ｒｐレーザ光を、エキシマレーザ７からは
、気相のＴＭＧ、アルシンではそれほど吸収されず、基
板に吸着したＴＭＧによって強く吸収されるＦ２レーザ
光を、成長容器中の基板上に照射した。Next, MOCVD epitaxial growth of a GaAs crystal layer using such a growth apparatus will be specifically explained. A CrO-doped semi-insulating GaAs wafer was used as the substrate. ■ Trimethyl gallium (
TMG), arsine was used as the group V raw material, and hydrogen was used as the carrier gas, diluent gas, and purge gas for the group (I) raw material. The supply amount of TMG and arsine is Q, 5 SCCm,
5 Q SCCm, total hydrogen flow rate is 500 sc
Cm and the pressure was set at f 10 Torr. When forming a GaAs crystal layer using the conventional method, the substrate temperature is
In this example, the substrate temperature was set at 400°C. During the growth of the crystal layer, the excimer laser 6 emits RP laser light, which is strongly absorbed in the gas phase by TMG and arsine, and the excimer laser 7 emits RP laser light, which is not absorbed as much by the gas phase TMG and arsine, but is adsorbed to the substrate. The substrate in the growth container was irradiated with F2 laser light, which is strongly absorbed by the TMG.
ＡｒＦレーザ光、Ｆ２レーザ光のレーザ出射口での強度
は、それぞれ、パルスあたり２ Ｑ ｍ ｊ ／ｅｘ
２．１ ｍ ｊ ／ａｎ ”で、繰り返しは８０ｐｐｍ
とした。The intensity at the laser exit of the ArF laser beam and the F2 laser beam is 2 Q m j /ex per pulse, respectively.
2.1 m j /an'' and the repetition rate is 80 ppm.
And so.
この様な方法により、ＡｒＦレーザ光とＦ２レーザ光を
照射して形成したＧａＡｓ結晶層と共に、ＡｒＦレーザ
光のみを照射して形成したＧａＡｓ結晶層、光を照射せ
ずに形成したＧａＡｓ結晶層を比較した。By such a method, a GaAs crystal layer formed by irradiating with ArF laser light and F2 laser light, a GaAs crystal layer formed by irradiating only ArF laser light, and a GaAs crystal layer formed without irradiation with light can be formed. compared.
光を照射しないで成長させた場合のＧ ａ Ａ ｓ結晶
層の成長速度は１０ ！ｙ ／ ｍ ｉｎ とたいへ
ん小さかったが、ＡｒＦレーザ光を照射することで成長
速度は２００＾／ ｍ ｉ ｎ と著しく増大した。The growth rate of the GaAs crystal layer when grown without irradiation with light is 10! Although the growth rate was very small at y/min, the growth rate was significantly increased to 200^/min by irradiation with ArF laser light.
ＡｒＦレーザ光とＦ！レーザ光を併せて照射しても成長
速度は２００Ａ／ｍｉｎ であり、Ｆ２ Ｌ／ −ｆ
光を照射しても成長速度の増大はみられなかった。ArF laser light and F! Even when irradiated with laser light, the growth rate is 200 A/min, and F2 L/-f
No increase in growth rate was observed even with light irradiation.
ここで、ＡｒＦレーザ光のみを照射して形成したＧ ａ
Ａ Ｓ結晶層と、Ａ ｒ Ｆ’ ｖ−ザ光とＦ’２Ｌ
／−−ｙ’光を照射して形成したＧａＡ３１晶層につい
てホール測定を行った。双方ともｐ型であったが、キャ
リア濃度はＡｒＦレーザ光のみを照射したものは１０
ｃｐｓ であったのに対し、Ａｒｌ；″レーザ光、
Ｆ！レーザ光共に照射したものは１０ ｔｔｍ で
あった。Ｆ！レーザ光を照射することにより、底面での
反応が励起され、未分解の■族有機金属原料から供給さ
れた結晶層中の炭素が減少したといえる。また、移動度
は、Ｆ２レーザ光を照射することにより増加することが
認められた。Here, Ga formed by irradiating only ArF laser light
A S crystal layer, A r F' v-the light and F'2L
Hall measurements were performed on the GaA31 crystal layer formed by irradiating /--y' light. Both were p-type, but the carrier concentration was 10 in the one irradiated with ArF laser light only.
cps, whereas Arl;''laser light,
F! The intensity of the laser beam irradiation was 10 ttm. F! It can be said that by irradiating the laser beam, the reaction at the bottom surface was excited, and the carbon in the crystal layer supplied from the undecomposed group Ⅰ organometallic raw material was reduced. Furthermore, it was found that the mobility increased by irradiation with F2 laser light.
上記実施例では光源としてエキシマレーザを用いたが、
用いる原料によシ、水銀ランプ、キセノン水銀ランプ、
重水素ランプ、あるいは希ガスの共鳴線等を用いること
もできる。これにフィルター等照射波長を限定する装置
を組み合わせてもよい。また、原料ガスは、ＴＭＧ、ア
ルシンをもちいたが、これに限るものではなく、トリエ
チルガリウム、トリメチルアルシン等の有機金属化合物
、あるいはハロゲン化物等を用いてもよい。In the above embodiment, an excimer laser was used as the light source, but
Depending on the raw materials used, mercury lamps, xenon mercury lamps,
A deuterium lamp, a rare gas resonance line, etc. can also be used. This may be combined with a device that limits the irradiation wavelength, such as a filter. Further, although TMG and arsine are used as the raw material gas, the present invention is not limited to these, and organometallic compounds such as triethyl gallium and trimethyl arsine, or halides may also be used.
本実施例においては、ＧａＡｓ結晶層の形成について述
べたが、これに限るものではな（、ＩｎＰａ ＡｌＧａ
Ａｓ、ＩｎＧａｐ等ｏｍ−ｖ族化合物半導体、ｚｎｓｅ
、Ｈｇｃｃｔ’ｒｅ等のＩＩ−■＆化化合物厚導体他の
半導体の形成に適用してもよい。In this example, the formation of a GaAs crystal layer was described, but the formation is not limited to this (InPa, AlGa,
Om-V group compound semiconductors such as As, InGap, ZNSE
The present invention may be applied to the formation of II-■& compound thick conductors such as Hgcct're and other semiconductors.
そのほか、本発明はその趣旨を逸脱しない範囲で種々変
形して実施することが出来る。In addition, the present invention can be implemented with various modifications without departing from the spirit thereof.
以上に述べたように、本発明によれば、吸着した原料ガ
スの吸収する波長の光を照射することによって、低温で
良質の半導体結晶層を形成するこ第１図は本発明の一実
施例を説明するための結晶成長装置を示すものである。As described above, according to the present invention, a high-quality semiconductor crystal layer can be formed at a low temperature by irradiating light with a wavelength that is absorbed by the adsorbed raw material gas. This figure shows a crystal growth apparatus for explaining.
ｌ・・・・・・成長容器、 ２・・・・・・基板、３
・・・・・・サセプタ。l...Growth container, 2...Substrate, 3
...Susceptor.
４・・・・・・ヒータ、 ５．１４．１５・・・・
・・ガス導入口。4...Heater, 5.14.15...
...Gas inlet.
６．７・・・・・・エキシマレーザ、 ８．９・・・
・・・レーザ光、 １０．１１・・・・・・反射ミ
ラー。6.7...Excimer laser, 8.9...
...Laser light, 10.11...Reflection mirror.
Claims (2)
成長法により半導体結晶層を形成する際に、基板に吸着
した原料ガスの吸収する１種又は複数の波長の光を照射
することを特徴とする半導体結晶層の形成方法。(1) When a source gas is introduced into a container containing a substrate and a semiconductor crystal layer is formed by vapor phase growth, light of one or more wavelengths absorbed by the source gas adsorbed on the substrate is irradiated. A method for forming a semiconductor crystal layer, characterized in that:
光を併せて照射することを特徴とする請求項１記載の半
導体結晶層の形成方法。(2) The method for forming a semiconductor crystal layer according to claim 1, characterized in that light of one or more wavelengths absorbed by the gaseous source gas is irradiated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6963988A JPH01243514A (en) | 1988-03-25 | 1988-03-25 | Formation of semiconductor crystal layer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6963988A JPH01243514A (en) | 1988-03-25 | 1988-03-25 | Formation of semiconductor crystal layer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01243514A true JPH01243514A (en) | 1989-09-28 |
Family
ID=13408633
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6963988A Pending JPH01243514A (en) | 1988-03-25 | 1988-03-25 | Formation of semiconductor crystal layer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01243514A (en) |
-
1988
- 1988-03-25 JP JP6963988A patent/JPH01243514A/en active Pending
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