JPH0323298A - Semiconductor crystal growth method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] The present invention relates to an improvement in a method for growing semiconductor crystals, in particular, an improvement that makes it possible to grow high-purity crystals at low temperatures using organometallic compounds. In addition, the metal-organic vapor phase method, which extremely reduces the content of carbon contained as an impurity in compound semiconductor crystals, and the atomic layer epitaxial method, which has so-called self-limiting characteristics, automatically controls the long film thickness. The purpose of the present invention is to provide a semiconductor crystal lengthening method that enables the lengthening of a semiconductor crystal, and one of the elements of the group M element 1 and the group II element 1 is a cyan group, a cyanomethyl group,
Produced using an organometallic vapor phase method in which the compound is supplied as a compound with one atomic group selected from the group of aminomethyl group, halogenated methyl vapor, trino\halogenated ethylene group, and monohalogenated ethylene group. Semiconductor crystal growth method, or one of the elements forming the set of 1 of the group ■ element and 1 of the group ,
Semiconductor crystal lengthening method using organometallic vapor phase epitaxy in which silicon or germanium is supplied as a compound with an atomic group selected from the group of monohalogenated ethylene groups, or silicon or germanium is supplied as a compound with an atomic group selected from the group of monohalogenated ethylene groups. produced using an organometallic vapor phase epitaxy method in which the compound is supplied as a compound with one atomic group selected from the group consisting of: It is prohibited to use semiconductor crystal growth methods. [Industrial Application Field] The present invention relates to an improvement in a method for growing semiconductor crystals, and in particular, to an improvement in which a high-purity crystal can be grown at low temperatures using an organometallic compound. [Prior Art] In recent years, compound semiconductors such as GaAs and InP have made remarkable progress, and ternary or quaternary mixed crystal semiconductors have become relatively easy to manufacture. Molecular beam epitaxy, metal organic chemical vapor deposition (hereinafter referred to as MO-CVD), atomic layer epitaxy (hereinafter referred to as ALE), etc. are widely used as methods for growing compound semiconductor crystals. In particular, in the MO-CVD method and ALB method,
Organic compounds of the elements that make up the semiconductor are used as raw materials for semiconductor crystal growth. (II to be solved by the invention!) In order to improve the performance of semiconductor devices, it is necessary to lower the growth temperature of semiconductor crystals and to grow high-purity semiconductor crystals. However, the trimethylgallium (Ga (CHz')) that has been used so far
), triethylgallium (Ga (Cz Hs )s
) and other organometallic compounds are used for low-temperature heating, the problem arises that the purity of the compound semiconductor decreases because the carbon contained in the organometallic compound is incorporated into the crystal and activated. ．． This phenomenon is considered to be an unavoidable problem as long as alkyl compounds such as methyl compounds or ethyl compounds are used as organic metal compounds used as raw materials. The purpose of the present invention is to eliminate this drawback, and to provide an organometallic vapor phase epitaxy method that enables low-temperature growth and extremely reduces the content of carbon contained as an impurity in compound semiconductor crystals, and the growth film thickness. The object of the present invention is to provide a method for growing a semiconductor crystal, which enables atomic layer epitaxial growth with so-called self-limiting characteristics, in which the growth is automatically controlled. (Means for solving !Ilfi) The above purpose can be achieved by any of the following means. An organic compound in which one element is supplied as a compound with l atomic group selected from the group of cyan group, cyanomethyl group, aminomethyl group, halogenated methyl group, trihalogenated ethylene group, and monohalogenated ethylene group. It is a semiconductor crystal growth method using the metal vapor phase method,
! Means I2 is such that one of the elements forming the set of 1 of group H element and 1 of group A semiconductor crystal growth method using an organometallic vapor phase method in which the compound is supplied as a compound with one atomic group selected from the group of halogenated ethylene groups,
The third means is a compound in which silicon or germanium is combined with one atomic group selected from the group consisting of a cyan group, a cyanomethyl group, an aminomethyl group, a halogenated methyl group, a trihalogenated ethylene group, and a monohalogenated ethylene group. This is a method for growing semiconductor crystals using the organometallic vapor phase method supplied as . [Function] The elemental bonding state of the organometallic compound used in the semiconductor crystal lengthening method according to the present invention is such that one element of the compound semiconductor, such as gallium or ingeum, is directly bonded to carbon; It is bonded via carbon to an atomic group containing nitrogen or a halogen group element. The bonding force between gallium, ingeum, etc. and carbon to be grown as crystals is
Compared to conventionally used alkyl compounds, the bonding force between elements such as gallium and indium and alkyl groups is weaker and easier to break, making low-temperature growth possible. On the other hand, the bonding force between carbon bonded to elements such as gallium and indium that cause the crystal to grow, and atomic groups containing nitrogen or halogen group elements is strong and difficult to break, so carbon separates and
There is less possibility that it will be incorporated into the crystal as an impurity. Furthermore, it is thought that the presence of nitrogen or a halogen group element in the molecule of this organometallic compound increases the polarization of the molecule as a whole, but when this organometallic compound is used in the atomic layer epitaxy method, A clear self-limiting effect can be obtained, and the growth temperature range of atomic layer epitaxy can be very wide. [Embodiments] Four embodiments of the present invention will be described below with reference to the drawings. As an example, Ga (CmHs) is used as a raw material for gallium.
! The relationship between a certain long temperature and a certain long speed when a GaAs crystal is grown on a substrate using CN and A s H s as the raw material for arsenic using the MO-CVD method is shown in 1a.
This is shown in graph A in the figure. Ga(CH
, )s, it was confirmed that low-temperature growth was possible compared to the relationship between a certain long temperature and growth rate (shown in graph B in Figure 1a) when using the conventional method using . Furthermore, when the concentration of carbon impurities in GaAs crystals was measured using the Van der Pauw method and the Photol-Neffsens method, it was confirmed that the concentration of carbon impurities in the GaAs crystal was about two orders of magnitude lower than that of conventional methods. For example, Ga (Cg Hs)g CN and AsH
When atomic layer epitaxial growth was performed at 500'C by alternately supplying Ga (Cx Hs)g CN onto the substrate, as shown in Figure 1b, the supply time of Ga(Cx Hs)gCN was lengthened. Also, it was confirmed that there is a two-cellular ξ-twisting effect in which the predetermined film thickness of Ga and As per l cycle is saturated at l atomic layer, and Ga (C.Hs)! C.N.
etc. were found to be suitable for the ALE method. As an example, Ga (CHzCl) is used as a raw material for gallium.
a, AsHs is used as the raw material for arsenic, and MO
-Graph A in Figure 2 shows the relationship between the growth temperature and a certain longitudinal velocity when a GaAs crystal is grown on a substrate using the CVD method.
It is shown in Compared to the relationship between a certain temperature and growth rate (shown in graph B in Figure 2) when using the conventional method of using Ga(CHs)1 as the raw material for gallium, low-temperature growth is possible. It has been confirmed that this has happened. Ma・ta・Va
As a result of measuring the carbon impurity concentration in GaAs crystals using the der Pauw method and the Photol ξNefsens method, it was confirmed that the concentration of carbon impurities in GaAs crystals was about two orders of magnitude lower than that of conventional methods. See Figure 3. For example, Ga (CHx Ci!)x and AsH3
When atomic layer epitaxial growth is performed at 400'C by alternately supplying Ga<CHxCl)s onto the substrate, as shown in FIG. The film thickness of Ga and As per 1 cycle is 1
It has been recognized that f1 has a self-limiting effect that saturates at the atomic layer, and Ga(CHiCL!). etc. were found to be suitable for the ALE method. Above, the GaAs crystal Kaicho was explained as an example, but the Zn. ．． Group ■ elements such as Hg and S. ．． ZnSe, ZnS, HgCdTe, etc. can be produced by using a compound of one of the Group Ⅰ elements such as Se and Te and the atomic group according to the gist of the present invention, using MO-CVD method, ALE method, etc. n-
It is also possible to produce a vr group compound semiconductor, and it is also possible to produce a compound of either one of the group Ⅰ elements such as Al and In and the group Ⅰ elements such as P and As, and the atomic group according to the gist of the present invention. using MO-CVD method and ALE method.
It is also possible to manufacture ■ and ■ group compound semiconductors such as As and InP. Furthermore, it is also possible to use a compound of Si or Ge and an atomic group according to the gist of the present invention, and to strictly control and increase the thickness of St or Ge on an atomic layer basis using ALE method etc. It is. [Effects of the Invention] As explained above, the organometallic compound used in the semiconductor crystal growth method according to the present invention contains an element for crystal growth and a cyan group, a cyanomethyl group, an aminomethyl group, or a methyl halide group according to the present invention. , the bonds with atomic groups such as trihalogenated ethylene groups and monohalogenated ethylene groups are weak and easy to break, making growth possible at low temperatures.
On the other hand, since the bond between carbon in the atomic group and the atomic group containing nitrogen or halogen group elements in the atomic group is strong and difficult to break, there is little possibility that carbon will be incorporated into the crystal, and the concentration of carbon impurities in the crystal will decrease. It gets lower. In addition, the organometallic compound used in the present invention is probably due to the large polarization of the entire molecule, but when the organometallic compound is purified using the ALE method,
A clear self-limiting effect can be obtained. Furthermore, since the living substances used in the present invention after the decomposition of the organometallic compound do not contain highly reactive substances such as hydrogen halides, there is no need to worry about corrosion of stainless steel piping, etc.

[Brief explanation of drawings]

Figure 1a shows Ga(c,Hs)! CN and A s
2 is a graph showing the relationship between a certain lengthening temperature and a lengthening rate of a GaAs crystal when organic metal vapor phase growth is performed using Hs. Figure 1b shows Ga(Cm Hs)tCN and AsH
Ga CCx Hs )t CN supply time and GaA when performing atomic layer epitaxial command using s
It is a graph showing the relationship with slIl thickness. Figure 142 is
Figure 3 is a graph showing the relationship between a certain long-term temperature and a certain long-term rate of GaAs when Ga (CHz Cj!)s and AsHs are used to form an organometallic vapor phase.
．． Cl)! 2 is a graph showing the relationship between the supply time of Ga (CHi Cl's) and Ga As III Jun when atomic layer epitaxial growth is performed using AsHs and AsHs.

Claims (1)

[Scope of Claims] [1] Organometallic vapor phase growth in which one of the group III elements (1) and V group element (1) is supplied as a compound with an atomic group listed below. A method for growing semiconductor crystals using the method. a, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Cyanogen group b, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Cyanomethyl group c, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Aminomethyl group d, ▲ Numerical formulas, chemical formulas, There are tables, etc. ▼ Methyl halide group e, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Trihalogenated ethylene group f, ▲ There are formulas, chemical formulas, tables, etc. ▼ Monohalogenated ethylene group However, R is from the halogen group is the selected element. [2] Made using an organometallic vapor phase epitaxy method in which one of the elements forming the group II element 1 and VI group element 1 is supplied as a compound with the atomic group listed below. Semiconductor crystal growth method. a, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Cyanogen group b, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Cyanomethyl group c, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Aminomethyl group Halogenated methyl group e, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Trihalogenated ethylene group f, ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ Monohalogenated ethylene group However, R is an element selected from the halogen group. [3] A semiconductor crystal growth method using an organometallic vapor phase epitaxy method in which silicon or germanium is supplied as a compound with an atomic group listed below. a, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Cyanogen group b, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Cyanomethyl group c, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Aminomethyl group d, ▲ Numerical formulas, chemical formulas, There are tables, etc. ▼ Methyl halide group e, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Trihalogenated ethylene group f, ▲ There are formulas, chemical formulas, tables, etc. ▼ Monohalogenated ethylene group However, R is from the halogen group is the selected element.