JPS6329820B2 - - Google Patents
Info
- Publication number
- JPS6329820B2 JPS6329820B2 JP54157682A JP15768279A JPS6329820B2 JP S6329820 B2 JPS6329820 B2 JP S6329820B2 JP 54157682 A JP54157682 A JP 54157682A JP 15768279 A JP15768279 A JP 15768279A JP S6329820 B2 JPS6329820 B2 JP S6329820B2
- Authority
- JP
- Japan
- Prior art keywords
- doping
- supply
- gas
- concentration
- doping 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.)
- Expired
Links
- 238000000034 method Methods 0.000 claims description 15
- 239000012535 impurity Substances 0.000 claims description 14
- 239000004065 semiconductor Substances 0.000 claims description 8
- 238000001947 vapour-phase growth Methods 0.000 claims description 5
- 239000013078 crystal Substances 0.000 claims description 4
- 239000007789 gas Substances 0.000 description 36
- 239000002994 raw material Substances 0.000 description 4
- 239000012808 vapor phase Substances 0.000 description 3
- 238000009792 diffusion process Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02612—Formation types
- H01L21/02617—Deposition types
- H01L21/0262—Reduction or decomposition of gaseous compounds, e.g. CVD
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02518—Deposited layers
- H01L21/02521—Materials
- H01L21/02538—Group 13/15 materials
- H01L21/02546—Arsenides
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02518—Deposited layers
- H01L21/0257—Doping during depositing
- H01L21/02573—Conductivity type
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
Description
【発明の詳細な説明】
本発明は気相成長半導体への不純物のドーピン
グ方法、特に低濃度のドーピング方法に関するも
のである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for doping impurities into a vapor-phase grown semiconductor, particularly to a method for doping at a low concentration.
各種半導体デバイスの作成のために、半導体気
相成長技術は不可欠であり、成長層への不純物の
ドーピング量を広範囲に、再現性よく制御する必
要がある。この場合反応管へ供給する不純物のガ
ス状原料としては、一般にボンベに充填されたガ
スが使用される。また、不純物の液体あるいは固
体状原料から発生する蒸気を適当な輸送用ガスに
よつて供給する場合もある。 Semiconductor vapor phase growth technology is essential for producing various semiconductor devices, and it is necessary to control the amount of impurity doped into the growth layer over a wide range and with good reproducibility. In this case, a gas filled in a cylinder is generally used as the impurity gaseous raw material to be supplied to the reaction tube. Alternatively, the vapor generated from impure liquid or solid raw materials may be supplied by a suitable transport gas.
従来上記のガス状原料による気相ドーピングに
よつて、不純物のドーピング量を制御するために
は、ドーピングガス中の不純物濃度およびその供
給速度を変化させてることが行なわれていた。こ
の方法には低濃度のドーピングにおいて次に述べ
る欠点を有している。すなわち、低濃度のドーピ
ングを行なうためにはドーピングガスの濃度を下
げ、さらに供給速度を小さくしなければならな
い。しかし、ドーピングガスとして低濃度、特に
10ppm以下の場合、濃度の精度、安定性が悪くな
り、供給速度に関しては微少な供給速度、特に10
c.c.／min、以下の制御は、現在最も優れた供給速
度制御装置であるマスフローコントローラを用い
ても精度が悪くなる。すなわち低濃度のドーピン
グを精度よく制御し、しかも再現性よく行なうこ
とは極めて困難であつた。そこでこれらの問題を
解決する方法として、濃度の精密、安定性を持た
せるために、ある程度高濃度のドーピングガス
と、該ドーピングガスとは別に用意した希釈用ガ
スとを用い、ドーピングを行なうときにこれら両
者の供給速度を制御して混合し、所要の濃度の低
濃度ガスを大量に作り、その一部を別の制御装置
を通して供給する方法が提案されている。この方
法によれば得られる低濃度ガスは滞留することな
く、混合された直後に反応管へ供給されるから、
濃度の精度、安定性はよいが、ガスの供給速度制
御装置が数多く必要となること、ドーピングガス
の大部分は利用されず捨てられるからドーピング
ガスの損失が多いという新たな欠点が生じる。 Conventionally, in order to control the amount of impurity doped by vapor phase doping using the above-mentioned gaseous raw material, the impurity concentration in the doping gas and its supply rate have been changed. This method has the following drawbacks when doping at low concentrations. That is, in order to perform doping at a low concentration, it is necessary to lower the concentration of the doping gas and further reduce the supply rate. However, as a doping gas, especially at low concentrations,
If it is less than 10ppm, the concentration accuracy and stability will be poor, and the supply rate will be very small, especially 10ppm.
Control of cc/min or less has poor accuracy even when using a mass flow controller, which is currently the most excellent supply rate control device. That is, it has been extremely difficult to control low concentration doping with high accuracy and with good reproducibility. Therefore, as a method to solve these problems, in order to ensure precision and stability of the concentration, a doping gas with a relatively high concentration and a dilution gas prepared separately from the doping gas are used when doping. A method has been proposed in which both of these gases are mixed by controlling their supply speeds to produce a large amount of low-concentration gas with a required concentration, and a portion of the gas is supplied through a separate control device. According to this method, the low concentration gas obtained does not stagnate and is supplied to the reaction tube immediately after being mixed.
Although the accuracy and stability of the concentration are good, new drawbacks arise in that many gas supply rate control devices are required, and most of the doping gas is discarded without being used, resulting in a large loss of the doping gas.
本発明の目的は、前記従来の欠点を除去し、低
濃度のドーピングを高精度で再現性よく実現させ
ることができる半導体への不純物ドーピング方法
を提供することにある。 SUMMARY OF THE INVENTION An object of the present invention is to provide a method for doping impurities into a semiconductor, which eliminates the above-mentioned conventional drawbacks and allows low concentration doping to be achieved with high precision and good reproducibility.
本発明によれば半導体結晶の気相成長時にドー
ピングガスを反応管内に供給して成長結晶中に不
純物をドーピングする方法において、前記ドーピ
ングガスの反応管内への供給をドーピングガスの
供給と停止を周期的に繰返すようにして行なうこ
とを特徴とする半導体への不純物ドーピング方法
が得られる。 According to the present invention, in a method of doping an impurity into a growing crystal by supplying a doping gas into a reaction tube during vapor phase growth of a semiconductor crystal, the supply of the doping gas into the reaction tube is periodically stopped. A method for doping impurities into a semiconductor is obtained, which is characterized in that the method is repeatedly carried out.
前に本発明の方法において使用するドーピング
ガスの濃度およびその供給速度は、従来のような
特別な低濃度、特別に設定された小さな供給速度
を選ぶ必要は全くない。 Regarding the concentration of the doping gas used in the method of the present invention and its supply rate, there is no need to select a particularly low concentration and a specially set small supply rate as in the conventional method.
すなわち、本発明の方法では、ドーピングガス
の供給および停止を短時間の周期で繰返すことに
より、実際上の供給量をドーピングガスを供給す
る時間と停止する時間との比によつて変化させよ
うとするものである。すなわちドーピングガスの
供給と停止の周期の中で供給時間を短かくするこ
とによりきわめて微少な供給速度を精度よく実現
させ、低濃度のドーピングを可能にしている。供
給と停止の周期が長い場合には、成長層中のドー
ピング濃度も厚さ方向に対しこれに対応した周期
で変動することになるが、通常は周期１秒程度で
完全に一定濃度にドーピングされた成長層が得ら
れる。条件によつてはさらに長時間でも可能であ
る。この点を以下に説明する。成長層中の不純物
のドーピング濃度は、ドーピングガスを断続させ
ても、次の理由によりそのまま完全に対応した変
動はしない。すなわち、第１に、ドーピング系の
配管および反応管内の一定体積の中でのガスの拡
散、混合作用があるために成長を行なわせる領域
ではドーピングガスの濃度が階段状の変化をせ
ず、充分に平均化されること。第２に、成長速度
が小さい場合、ドーピングガスの供給と停止の周
期の間に成長する成長層の厚さはひじように小さ
く、実際上は一定のドーピングが行なわれるこ
と。気相成長法での成長速度は通常10〜100Å／
secであり、成長層の原子間距離は数Åであるか
ら、周期を0.1秒以下とすれば、上述の第１の効
果が全くない場合でも完全に一定濃度となる。ま
た、成長速度が小さい程、周期は長くてもよい。
第３に、いつたん成長した成長層中においても固
体中の拡散のためドーピング濃度の変化はゆるや
かとなることである。以上の効果によつてドーピ
ングガスを供給、停止させても、その周期が短い
場合には、供給と停止の時間比、供給時のドーピ
ングガスの濃度と供給速度によつて決定される平
均値にドーピングされることになる。供給と停止
の時間比は、例えば適当な電気回路と電磁弁を用
いれば容易に高精度で変化させることが可能であ
る。 That is, in the method of the present invention, by repeating the supply and stop of doping gas in a short period of time, the actual supply amount is attempted to be changed depending on the ratio between the time for supplying doping gas and the time for stopping doping gas. It is something to do. That is, by shortening the supply time in the cycle of supplying and stopping the doping gas, an extremely small supply rate can be achieved with high precision, making it possible to perform doping at a low concentration. If the cycle of supply and stop is long, the doping concentration in the growth layer will also fluctuate at a corresponding frequency in the thickness direction, but normally the doping concentration is completely constant within a period of about 1 second. A grown layer is obtained. Depending on the conditions, even longer periods of time are possible. This point will be explained below. Even if the doping gas is interrupted, the doping concentration of the impurity in the growth layer does not change completely for the following reason. Firstly, the concentration of the doping gas does not change in a stepwise manner in the region where growth is performed due to gas diffusion and mixing within a certain volume within the doping system piping and reaction tube. be averaged to Second, when the growth rate is low, the thickness of the growth layer that grows between periods of doping gas supply and stop is as small as an elbow, and in practice constant doping is performed. The growth rate in vapor phase growth is usually 10 to 100 Å/
sec, and the interatomic distance of the grown layer is several angstroms, so if the period is 0.1 seconds or less, the concentration will be completely constant even if the above-mentioned first effect is not present at all. Furthermore, the lower the growth rate, the longer the period may be.
Thirdly, even in the growth layer once grown, the doping concentration changes slowly due to diffusion in the solid. Even if the doping gas is supplied and stopped due to the above effects, if the cycle is short, the average value determined by the time ratio of supply and stop, the concentration of doping gas at the time of supply, and the supply speed will be reduced. You will be doped. The supply and stop time ratio can be easily varied with high precision, for example, by using a suitable electrical circuit and solenoid valve.
次に、本発明を気相成長GaAsでのH2Sによる
ドーピングに適用した一実施例について説明す
る。ドーピング用原料ガスとしてはH2S14.8ppm
のボンベガスを使用し、ドーピングガスの供給速
度は、最大供給速度50c.c.／min.のマスフローコ
ントローラを使用した。ドーピングガスは、常に
このマスフローコントローラによつて一定供給速
度に制御して連続的に流し、三方電磁弁あるいは
二個の二方電磁弁の組合せによつて反応管への供
給を断続させた。すなわち、反応管への供給が停
止されているときはドーピングガスは排気口から
捨てられる。これは、使用したマスフローコント
ローラの応答速度が遅く、マスフローコントロー
ラに流れるガスを直接断続すると、供給速度の精
度が悪くなるためで本発明の本質ではない。上述
のドーピングガスを15c.c.／minで連続的に供給し
た場合、得られた成長層のキヤリア濃度は5.8×
1016cm-3となつた。他の成長条件を同一に保つ
て、ドーピングガスの供給の断続の周期を２秒と
して、供給する時間を0.1〜１秒の間で変化させ
た結果、得られた成長層のキヤリア濃度は、ドー
ピングガスの平均供給速度に比例して変化し、
2.5×1015cm-3〜3.0×1016cm-3のキヤリア濃度が再
現性よく得られ、厚さ方向でのキヤリア濃度の変
化も認められなかつた。 Next, an example in which the present invention is applied to doping with H 2 S in vapor-phase grown GaAs will be described. H 2 S 14.8ppm as raw material gas for doping
A mass flow controller with a maximum supply rate of 50 c.c./min. was used for the doping gas supply rate. The doping gas was constantly controlled to a constant supply rate by the mass flow controller, and the supply to the reaction tube was interrupted by a three-way solenoid valve or a combination of two two-way solenoid valves. That is, when the supply to the reaction tube is stopped, the doping gas is discarded from the exhaust port. This is not the essence of the present invention because the response speed of the mass flow controller used is slow, and if the gas flowing to the mass flow controller is directly interrupted, the accuracy of the supply rate deteriorates. When the above doping gas is continuously supplied at 15c.c./min, the carrier concentration of the resulting growth layer is 5.8×
10 16 cm -3 . By keeping other growth conditions the same and changing the doping gas supply period between 0.1 and 1 second with an intermittent cycle of 2 seconds, the carrier concentration of the resulting growth layer was varies proportionally to the average gas supply rate,
A carrier concentration of 2.5×10 15 cm −3 to 3.0×10 16 cm −3 was obtained with good reproducibility, and no change in carrier concentration was observed in the thickness direction.
以上明らかなように本発明は気相成長中に低濃
度の不純物ドーピングを行なう方法として極めて
有効な方法である。 As is clear from the above, the present invention is an extremely effective method for doping impurities at a low concentration during vapor phase growth.
Claims (1)
反応管内に供給して成長結晶中に不純物をドーピ
ングする方法において、前記ドーピングガスの反
応管内への供給をドーピングガスの供給と停止を
成長層中の厚さ方向の不純物分布が一様となる速
さで周期的に繰返しさらにこの供給と停止の周期
を変化させることにより前記不純物の濃度を制御
することを特徴とする半導体への不純物ドーピン
グ方法。1. In a method of doping impurities into a growing crystal by supplying a doping gas into a reaction tube during vapor phase growth of a semiconductor crystal, the supply and stopping of the doping gas into the reaction tube are controlled depending on the thickness of the growth layer. A method for doping impurities into a semiconductor, characterized in that the concentration of the impurity is controlled by periodically repeating the supply and stopping at a speed that makes the impurity distribution uniform in the transverse direction, and by changing the period of supply and stop.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15768279A JPS5680127A (en) | 1979-12-05 | 1979-12-05 | Method of impurity doping to semiconductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15768279A JPS5680127A (en) | 1979-12-05 | 1979-12-05 | Method of impurity doping to semiconductor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5680127A JPS5680127A (en) | 1981-07-01 |
| JPS6329820B2 true JPS6329820B2 (en) | 1988-06-15 |
Family
ID=15655075
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15768279A Granted JPS5680127A (en) | 1979-12-05 | 1979-12-05 | Method of impurity doping to semiconductor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5680127A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2742789B2 (en) * | 1987-08-12 | 1998-04-22 | セイコーエプソン株式会社 | Silicon thin film manufacturing method and silicon thin film manufacturing apparatus |
-
1979
- 1979-12-05 JP JP15768279A patent/JPS5680127A/en active Granted
Non-Patent Citations (2)
| Title |
|---|
| APPLIED PHYSICS LETTERS=1971 * |
| DIGEST OF TECH. PAPERS=1979 * |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5680127A (en) | 1981-07-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4859627A (en) | Group VI doping of III-V semiconductors during ALE | |
| US5254210A (en) | Method and apparatus for growing semiconductor heterostructures | |
| US6281036B1 (en) | Method of fabricating film for solar cells | |
| JPS60245218A (en) | Method and apparatus for producing semiconductor element | |
| US3348984A (en) | Method of growing doped crystalline layers of semiconductor material upon crystalline semiconductor bodies | |
| US4279670A (en) | Semiconductor device manufacturing methods utilizing a predetermined flow of reactive substance over a dopant material | |
| Irvine et al. | A study of transport and pyrolysis in the growth of CdxHg1ȡxTe by MOVPE | |
| JPS6329820B2 (en) | ||
| US5296088A (en) | Compound semiconductor crystal growing method | |
| Seki et al. | New Methods of Vapour Phase Epitaxial Growth of GaAs | |
| JP3052269B2 (en) | Vapor phase growth apparatus and growth method thereof | |
| JPH0529234A (en) | Epitaxial crowing method | |
| JPS5986215A (en) | Vapor growth method of gallium arsenide | |
| JPH04162418A (en) | Chemical vapor growth method | |
| JPS6216011B2 (en) | ||
| Kisker et al. | Mechanism of graphite baffle gettering in organometallic vapor phase epitaxy; Adsorption of trimethylaluminum on graphite | |
| JPS5856964B2 (en) | Compound semiconductor liquid phase growth method | |
| JPS6072220A (en) | Device for vapor phase epitaxial growth | |
| JPH0620050B2 (en) | Gas dilution device | |
| RU1820783C (en) | Method for producing epitaxial gallium arsenide layers | |
| JPS60145999A (en) | Gaseous-phase growth of compound semiconductor | |
| JPS5572030A (en) | Gas phase growing of compound semiconductor | |
| JPS59172717A (en) | Semiconductor vapor growth equipment | |
| JPS5816329B2 (en) | Hika Gallium | |
| JPS61187226A (en) | Vapor growth apparatus |