JPS60211824A - Vapor growth means of group iii-v compound semiconductor device - Google Patents

Abstract

PURPOSE:To the improve the quality by a method wherein growth is made by the flow amount above C and below A, where the amount of chloride of the group V element is assumed as A, and the amount of group V element chloride against the organic group III metallic element is one third, is assumed as B, and the flow amount of the group III element chloride at the point where A and B is internally devided as 1:2, is assumed as C. CONSTITUTION:When the epitaxial growth of GaAs is performed using the trimethylgallium (TMG) as organic group III metal and trichloride arsenide (AsCl3) as the group Velement, AsCl3 flow A, with which the growth competes in etching, enabled to be obtained as AsCl3 bubble flow in which DELTAw becomes zero by the relation of weight variation DELTAw(mg) before and after the growth of the semi-insulation GaAs substrate and the flow of AsCl3 and also enable to be obtained bubble flux B of AsCl3 where the ratio of AsCl3 to TMG is one third by culculation. The point C which the internal division of A and B at 1:2 becomes C=(2A+B)/3. In case of the bubble flow of AsCl3 below C, the nuclear growth of GaAs onto SiO2 is observed. But in case of the bubble flow of AsCl3 above C, the crystal growth of GaAs is not observed on the SiO3 at all. According to this, a high quality crystal whose electical characteristic is practical is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a technique for selectively epitaxially forming a 11-V group compound semiconductor on an E-2 group IH metal semiconductor substrate.

(Prior art and its problems) The selective growth technology of 1-V group compound semiconductors is the 11th technology that should be used as a means of device isolation or for the purpose of forming local contact layers and passivation films. For example, an example of applying the chloride method as a selective growth technique is given in the Journal of Religion Nostalgic Growth Vol.
Published by Nis Iida and Kei Itoo on pages 336 to 341 of Volume 3.14 combined issue.

911, which applies the MOVPE method as a selective growth technology,
With some improvements, as flJ adding HCl, P. of the Journal of the Electrochemical Society Vol.
Presented by Ray Chaudno and D.K. Jurouder, diethylgallium chloride contains C6 as a group I element organic compound.

An example of using ((C, ni) to, +cl) is the presentation by Rei Nakayama, Nis Okawa, and H Ishikawa in Fujitsu Scientific and Technical Journal, Vol. 13, No. 3, pages 53 to 68. , or as an example of a typical application of the MOVPE method, the journal
Of Crystal Growth Vol. 55, pp. 229-23
There are four pages of presentations by Earl Azoulay, N. Bouadma, J.C. Prey, and El Bi Dougran. Recently, there have been attempts to perform the MOVP E method in a high-vacuum MBE apparatus, and the selectivity in growth was discussed at the 15th Conference on Solid State Devices and Materials C-4-ILN. It has been announced.

However, in the chloride method, it takes time for the group I elements to saturate the group metal source, and a metamorphosed layer of the group I-V compound semiconductor is epitaxially grown in the early stage of growth. Although there is no mention of the electrical characteristics of the layer, it is assumed that there are problems with its quality for practical use. In addition, a selective growth method in which HCI is added to the MOVPE method and an MOVP method using diethyl gallium chloride as a raw material.
Even though the E method has a certain degree of selectivity, the I-V
Nuclear growth of the IV group compound semiconductor occurs on surfaces other than the group compound semiconductor substrate, resulting in a lack of reliability in device isolation. In the typical M, 0 VPE method, there is no selectivity in growth and the crystallinity differs only between the I-V group compound semiconductor substrate and the other substrates, which is far from selective growth in the original sense. Although it is reported that M) VPE under high vacuum has perfect selectivity and does not grow at all on anything other than ■-V group compound semiconductor substrates, the crystals are p-type with low resistance and are contaminated with a large amount of carbon. Conceivable.

(Object of the Invention) The object of the present invention is to eliminate such conventional drawbacks and to
An object of the present invention is to provide a 1-V group compound semiconductor vapor phase growth method for epitaxially growing a -V group compound semiconductor selectively only on a -V group compound semiconductor.

(Structure of the Invention) According to the present invention, in a vapor phase growth method in which an organic group I metal vapor and a group II element are grown, the flow rate of group Assuming that the conditions are constant, the flow rate of Group ■ element chloride at which the ratio of Group ■ element chloride to organic mouse group metal element is one-third is B, and A and B.
Vapor phase growth of a group IV compound semiconductor, characterized in that growth is performed at a flow rate of group V element chloride of C or more and A or less, where C is the flow rate of group V element chloride at a point where method is obtained.

(Detailed Description of Configuration) The present invention solves the problems of the prior art by adopting the above-described configuration.

A vapor phase growth method in which organic Group I metal vapor and Group ■ element chloride vapor are reacted in a hot-wall type reaction tube to epitaxially grow a Group I-■ compound semiconductor on a downstream substrate is described in Japanese Patent Publication No. 1977-2900. Disclosed. According to this method of vapor phase growth of A-2 group compounds, the cause of formation of metamorphic layers in the early stage of growth in the chloride method can be eliminated. Moreover, under the growth conditions that the present inventors were able to define through extensive experimentation, the above vapor phase growth method can be defined as a selective vapor phase growth technique for the IV group compound semiconductor substrate-1. The advantage of the hot wall type is that under the growth conditions of the present invention, no total <' IV group compound semiconductor is precipitated on the wall of the reaction tube on which the substrate is placed. The I-III group compound semiconductor will not fall from the surroundings and cause defects in the growing crystal.

(Example) Examples of the present invention will be described in detail below with reference to the drawings. Figure 1 shows how organic Group I metal vapor and Group ■ element salt F arsenide vapor are reacted in a hot wall reaction tube to epitaxially grow a ■-V Group compound semiconductor on a downstream substrate.
This shows a vapor phase growth apparatus that performs a phase growth method.

Trimethyl gallium (TMG) as an organic group I metal,
GaAs was grown epitaxially using arsenic trichloride (AsC/!,) as a group element chloride.

Hydrogen gas 2 containing TMG passes through the introduction pipe cooled with cooling water 1, and hydrogen gas 3 containing Ascl from the outside thereof is heated in an electric furnace 4 into a hot wall type reaction tube 5.
GaAs introduced into the
GaAS is epitaxially grown on the substrate.

ASCl whose growth and etching are antagonistic in the present invention;
The flow rate A was determined as follows. Figure 2 shows an area of 3cW.
1 shows the relationship between the weight change Δw (m9) before and after growth of a semi-insulating GaAs substrate with a thickness of 400 μm and the kSce3 flow rate. TM (set at 12°C, 428CCM
(Standard cubic centimeter per
Minutsu) caused a bubble. The growth temperature was set at Huff 40°0.

The dilution hydrogen flow rate was 500 SCCM. As(J) set at 18°0, when the bubble hydrogen flow rate is increased, the experimental value of ΔW in the white circle in Figure 2 will eventually become negative.
J, taken as bubble flow rate. A m C13 vs TM
The AsC6 bubble flow rate B, where the G ratio is 1/3, is calculated by OTMG, - (pull flow rate is FTMO, ks
cls bubble flow rate pAscJ3TMG vapor pressure PT
MG (2-Of 76 tlorr), As”l
The vapor pressure of s is PacJ! , (7.67orr at 18°0
), the total pressure inside the bubbler is P, then ksCl, vs. TMG
The ratio R becomes.

If the flow rates of A and B are determined by experiment and calculation, the l of AB is
The internal division point C of :2 is 2A+B C== −.

In this example, it was found through experiments that A il: 3358 CCM, as shown in FIG. B was calculated to be 1558 ccM9, and is shown in FIG. As a result, C was 2758 CCM.0 Although the detailed mechanism is not clear, in epitaxial growth of GaAs on a GaAs substrate partially masked with SjO, with the flow rate of C as a boundary, ks below C
At Cl and bubble flow rates, GaAs nucleus growth was observed on 5tOt, whereas at CJ and bubble flow rates, no crystal growth of GaAs was observed on Siq. is non-doped, n-type, and has a carrier concentration of 5 x 10" Cl11-3.The carrier mobility at room temperature is 6000 cm/■.0 Although GaAs was used in all the above explanations, the method of the present invention The present invention can also be applied to other yam-III group semiconductors such as , GaP, etc.

(Effects of the Invention) As is clear from the above explanation, according to the present invention, an extremely perfect selective 1-V group compound semiconductor vapor phase growth method can be obtained, and the electrical properties of the crystal are of good quality for practical use. 0 shown to be

[Brief explanation of drawings]

FIG. 1 is a diagram showing a vapor phase growth apparatus in which the present invention is implemented. l...Cooling water, 2...Hydrogen gas containing TMG, 3...Hydrogen gas flow containing As(J), 4
・・・・・・Electric furnace 5・・・Hot wall type reaction tube 6・・・・・・Substrate 0 Figure 2 shows the change in substrate weight before and after growth, kscl, bubble water flow rate and This is a diagram showing the relationship between OA and AsC, where growth and etching are antagonistic.
1. Bubble flow rate, B is As(J, ratio to TMG is 1/3
This is the AsCl3 bubble flow rate and the ksc13 bubble flow rate that internally divides C11iAB into 1:2. Representative Patent Attorney Susumu Uchihara / Figure 2 0100 200 300 400 F ASCI3 (SCCM)

Claims (1)

[Claims] In a vapor phase growth method in which organic group I metal vapor and group Ⅰ element chloride vapor are reacted in a hot-wall reaction tube to epitaxially grow a group Ⅰ compound semiconductor on a downstream substrate, a group V element whose growth and etching are competitive. Chloride flow rate is A
The growth conditions other than this flow rate are constant, and the flow rate of group V element chloride at which the ratio of group V element chloride to organic group I metal element is one-third is B, and A and B are internally divided into 1 = 2. A method for vapor phase growth of a group IV compound semiconductor, characterized in that growth is performed at a flow rate of group V element chloride of C or more and A or less, with the flow rate of group V element chloride at the point being C.