JPS6398121A - Vapor growth method - Google Patents

Abstract

PURPOSE:To obtain a crystal of high quality with good uniformity over a large area without using virulently poisonous phosphine or arsine by evaporating group V single substance element as V material gas in a crystal growing chamber for use. CONSTITUTION:Group V single substance element which becomes a V material 4, such as phosphorus is filled in a carbon crucible 3 or a quartz crucible 6 at the upstream of a susceptor 2 or adjacent to the upstream, the material 4 is evaporated by a heat or a light, and supplied as the material 4. Thus, since arsine (AsH3) or phosphine (PH3) being virulently poisonous is not used as the material gas at all, the safety is improved, and since it is supplied in a P-type, an intermediate reaction with TEI (triethyl indium) is eliminated to obviate the formation of (TEI-Ph3)n polymer which does not contribute to a crystal growth, and the growing velocity can be controlled in a wide range.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vapor phase growth method used for growing crystals of compound semiconductors and the like on a substrate.

2. Description of the Related Art In recent years, vapor phase epitaxial growth methods for compound and mixed crystal semiconductors such as ■-■ group and ■-■ group, particularly metal organic vapor phase epitaxy (MOVPE), have been developed.
The por phase epitaxy method) is attracting attention because of its uniformity over a large area, mass productivity, controllability of film thickness and composition, etc., and research and development are being actively conducted in various places.

Conventionally, this type of vapor phase growth apparatus has had a structure as shown in FIG. 1 is a quartz furnace core tube, and 2 is a carbon susceptor. For example, when growing an InP crystal in a vapor phase, organic In compounds such as trimethylindium TMI ((CH3) 3In) or triethylindium TEI ((C, H5) 3In) are used as the In source gas, and extremely toxic phosphine gas PH3 is used. In addition, when growing a GaAs crystal in a vapor phase, Ga
Using an organic Ga compound such as trimethylgallium TMG ((CH3)5Ga) or triethylgallium TEG ((C2H5)3Ga) as the raw material gas for As
As a raw material gas, arsine gas A s Hs, which is extremely toxic like P, is used. In addition, in the case of InP crystal growth,
When TEI is used, PH3 can be easily (T
EI-PH3] Since a polymer is formed, PH
It was necessary to disassemble P3 and supply it as P2 or P4.

Also, as a method using solid as a raw material, G a A s
In the case of Ga as a solid, A s Cl 3 is used, and in the case of InP, Irr and PCl 3 are used, but As or P has not been used as a solid.

Problems to be Solved by the Invention As mentioned above, arsine A s, which is highly poisonous to Group III raw material gases,
Since Hs and phosphine PH3 are used, the crystal growth apparatus not only needs to be kept sufficiently confidential, but also the surrounding area of the apparatus must be kept safe, making the apparatus itself very expensive. Furthermore, in order to avoid the formation of a polymer in which TEI and PH3 react and do not contribute at all to crystal growth (:TEI-PH3:), the group III raw material and the group III raw material gas are introduced into the crystal growth chamber through respective introduction pipes. Methods have been proposed in which the introduced PH3 is cracked in advance and introduced into the crystal growth chamber in the form of P2 or P4, but all these methods tend to make the equipment more complex.

Means for Solving the Problems The present invention provides, as a means to solve the above problems, a group V material, which is a group V raw material, in a carbon crucible or a quartz crucible on the upstream side of a susceptor or adjacent to the upstream side. A single element is introduced, and the group (I) raw material is evaporated by heat or light to be supplied as a group V raw material.

For production The effect of this technical means is as follows.

Safety is improved because arsine (AsHa) and phosphine (PH3), which are extremely toxic, are not used at all as the Group (2) raw material gas. In addition, since it is supplied in the form of P, there is no intermediate reaction with TEI, and it does not contribute to crystal growth (TEI-PH
3] The formation of eupolymer has been eliminated, and the growth rate can now be controlled over a wide range.

EXAMPLE A specific example of a vapor phase growth apparatus used in the present invention is shown in FIG. 1 is a quartz furnace core tube, 2 is a carbon fissure susceptor, 3 is a carbon crucible, and 4 is a group V raw material, such as phosphorus. In this embodiment, the carbon crucible 3 is placed upstream and adjacent to the susceptor, and the carbon crucible and the susceptor can be heated simultaneously by using a high frequency induction heating device.

The carbon crucible 3 may be integrated with the susceptor. InP was grown on a 2° substrate using the apparatus according to this example. ■ TMI or T as a group raw material gas
EI was used. The carrier gas is a high-purity hydrogen gas that has passed through a Pd diffusion film and has a flow rate of 3.217 m1n. Board 2o
is InP, and the substrate temperature is 600 to 660°C. TM
When using I, keep the temperature of the Bapra container at 17°C,
Flow hydrogen at 60cc/ynin. Also, when using TEI, the temperature of the bubbler container is kept at 36℃, and the hydrogen is heated to 100℃.
cc/=flow and bubble. Set the temperature of the susceptor to 60
When maintained at 0°C, the temperature of the carbon crucible 3 adjacent to the upstream side of the susceptor becomes 550°C. When both TMI and TEI were supplied in the same molar number, there was almost no difference in the growth rate. It was found that the half width of photoluminescence at 77K was 9 or less, and that an extremely good crystalline film was obtained on the substrate 2o.

A second embodiment will be described using FIG.

P (phosphorus) is placed in a quartz glass crucible 8 and exposed to light 6.
For example, infrared rays, laser light, or microwaves are used to raise the surface temperature of the phosphor and evaporate it. In this case, the susceptor 2 and the phosphor are independent, and the amount of phosphorus supplied can be controlled by the power of the light 5 or microwave.

If the hydrogen introduced into the furnace core tube is heated in advance by the heater 9 provided at the entrance of the furnace core tube, a drop in the surface temperature of phosphorus can be prevented and phosphorus can be stably supplied. 8 is cooling water, and 10 is a high frequency coil.

In this case as well, TMI or TEI
By introducing this, an extremely good InP crystal thin film can be easily grown over a large area substrate 20 (2 inch wafer). Furthermore, when the same mole number of TMI and TEI was supplied, there was almost no difference in the growth rate. Therefore, the generally said TEI and PH
There is no need to take into account the reduction in growth rate due to the intermediate reaction in step 3, and the device itself can be of simple structure.

In the above embodiments, the growth of InP has been described.
By adding arsenic (As) to the material, GaAs or AIGaAs can be easily grown. Furthermore, it goes without saying that if Se or S is used, it can be applied to ■-■ group compound semiconductors such as Zn5e and ZnS.

Effects of the Invention In the vapor phase growth method of the present invention, a single element of a group III element, which is a group III raw material, is placed in a carbon crucible or a quartz glass crucible on the upstream side of a susceptor or adjacent to the upstream side, and a group V raw material is evaporated. It can be supplied as a Group Ⅰ raw material, and phosphorus and arsenic can be supplied without using extremely poisonous phosphine or arsine, dramatically improving safety.

In addition, in InP-based crystal growth, (TE I -PH
3) It is possible to avoid the formation of polymers that do not contribute to the growth of crystals, and the growth efficiency that contributes to the growth of TEI or TMI is dramatically improved, eliminating waste. Therefore, since a high quality crystal can be obtained with good uniformity over a large area, it is possible to significantly reduce the cost of devices made from this crystal, which has a very practical effect.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a vapor phase growth apparatus according to a first embodiment of the present invention, FIG. 2 is a schematic diagram of a vapor phase growth apparatus according to a second embodiment, and FIG. 3 is a schematic diagram of a conventional vapor phase growth apparatus. It is a schematic diagram. 1...Quartz furnace core tube, 2...Carbon susceptor, 3...Carbon crucible, 4,7.
...phosphorus, 6 ... light, 6 ... quartz glass crucible. /-Ishisami Nito Insikoya≧ 6-“JEδ
に力°Ranoge coarse crucible 2---Carbon i Ahibuta
3.-.
9-Heater 47-Rin 10-Takaen Ronrui1. , 5-A zo-plate Fig. 2/-m-quartz and heart sound 2-11 carbon four carhibuta Fig. 3

Claims (3)

[Claims] (1) When forming a semiconductor thin film on a substrate on a susceptor placed in a crystal growth chamber using an organometallic compound containing a group III element as a group III source gas, a group V element is used as a group V source gas. A vapor phase growth method in which a single substance is evaporated in the crystal growth chamber. (2) Group V elements were placed in a carbon or quartz glass crucible installed adjacent to and upstream of the susceptor, and evaporated using high-frequency induction or heat radiated from the susceptor. A vapor phase growth method according to claim 1. (3) The group V element is placed in a carbon or quartz glass crucible installed upstream of the susceptor, and is evaporated by heating with light or microwaves. The vapor phase growth method according to item 1.