Tris(trichlorosilyl)dichlorogallylgermane, process for the preparation thereof and use thereof

Abstract

A process can be used for the preparation of tris(trichlorosilyl)dichlorogallylgermane, which is a chlorinated, uncharged substance.

Claims

1: Tris(trichlorosilyl)dichlorogallylgermane of the formula (I): ##STR00003##

2: A process for preparing the tris(trichlorosilyl)dichlorogallylgermane according to claim 1, the process comprising: (a) mixing at least one tris(trichlorosilyl)germanide salt of an [X][Ge(SiCl.sub.3).sub.3] type, wherein X=ammonium (R.sub.4N) and/or phosphonium (R.sub.4P), and R=n alkylic or aromatic radical, with GaCl.sub.3, to obtain a mixture, and (b) reacting the mixture in an environment consisting of at least one chlorinated hydrocarbon at a temperature of 5 to 40° C., to obtain a crude product comprising salts [R.sub.4N][GaCl.sub.4] and/or [R.sub.4P][GaCl.sub.4] and tris(trichlorosilyl)dichlorogallylgermane, and subsequently (c) introducing said crude product into at least one nonpolar solvent and separating off insoluble residue, and subsequently (d) removing the at least one nonpolar solvent, to obtain tris(trichlorosilyl)dichlorogallylgermane.

3: The process according to claim 2, wherein in (b), the reaction is conducted at room temperature, and/or wherein in (d), the at least one nonpolar solvent is removed at room temperature.

4: The process according to claim 2, wherein in (b), the at least one chlorinated hydrocarbon is dichloromethane CH.sub.2Cl.sub.2.

5: The process according to claim 2, wherein in (b), R=Et.

6: The process according to claim 2, wherein in (c), the at least one nonpolar solvent is selected from the group consisting of hexane, n-hexane, pentane, and benzene.

7: The process according to claim 2, wherein in (a), [X][Ge(SiCl.sub.3).sub.3] and GaCl.sub.3 are mixed by stirring, in (b), the mixture obtained in (a) is completely dissolved in the at least one chlorinated hydrocarbon, and after a time of 0.1 to 24 hours, the at least one chlorinated hydrocarbon is removed.

8: The process according to claim 2, wherein in (c), after the introduction of the crude product, the temperature of the at least one nonpolar solvent is brought for from 1 to 5 times, from room temperature to an elevated temperature and is subsequently allowed to cool.

9: A method of deposition of gallium-doped Si—Ge layers, the method comprising: using the tris(trichlorosilyl)dichlorogallylgermane according to claim 1 as a precursor for the deposition of gallium-doped Si—Ge layers.

10: The process according to claim 6, wherein the at least one nonpolar solvent is n-hexane.

11: The process according to claim 7, wherein [X][Ge(SiCl.sub.3).sub.3] and GaCl.sub.3 are in a solid state.

12: The process according to claim 7, wherein the mixing in (a) is performed in an oxygen-free environment.

13: The process according to claim 7, wherein the mixing in (a) is performed under protective gas, nitrogen, or argon.

14: The process according to claim 7, wherein in (b), the at least one chlorinated hydrocarbon is removed after 1 to 5 hours.

15: The process according to claim 7, wherein in (b), the at least one chlorinated hydrocarbon is removed at room temperature.

16: The process according to claim 7, wherein in (b), the at least one chlorinated hydrocarbon is removed in an oxygen-free, dry environment.

17: The process according to claim 7, wherein in (b), the at least one chlorinated hydrocarbon is removed at a pressure in a range from 1 to 500 hPa.

18: The process according to claim 8, wherein the nonpolar solvent is brought for 3 times from room temperature to an elevated temperature.

19: The process according to claim 8, wherein the elevated temperature is a boiling point temperature of the at least one nonpolar solvent.

20: The process according to claim 8, wherein the cooling of the at least one nonpolar solvent is to room temperature.

Description

EXAMPLE 1: PREPARATION OF TRIS(TRICHLOROSILYL)DICHLOROGALLYLGERMANE (1)

[0038] The synthesis was effected in accordance with Equation 1 from [Et.sub.4N][Ge(SiCl.sub.3).sub.3] with GaCl.sub.3 while adding CH.sub.2Cl.sub.2.

##STR00002##

[0039] The reaction was conducted in a glovebox.

[0040] [Et.sub.4N][Ge(SiCl.sub.3).sub.3] at an amount of 0.050 g, corresponding to 0.082 mmol, and GaCl.sub.3 at an amount of 0.028 g, corresponding to 0.16 mmol, were mixed in the solid state and subsequently completely dissolved in dichloromethane CH.sub.2Cl.sub.2.

[0041] The dichloromethane was slowly evaporated at RT after 3 hours. After one day, a mixture of Ge(SiCl.sub.3).sub.3GaCl.sub.2 (1) and [Et.sub.4N][GaCl.sub.4] had formed as crystalline crude product. The crude product was heated to boiling three times with in each case 7 ml of n-hexane. Subsequently, the clear, colourless n-hexane solution was separated off from the insoluble residue with a syringe.

[0042] The nonpolar solvent was subsequently removed slowly at RT, and after one day it was possible to isolate Ge(SiCl.sub.3).sub.3GaCl.sub.2 (1) as a crystalline substance.

[0043] The .sup.29Si NMR spectrum of the inventive product 1 is presented in FIG. 1a, and the result of the analysis thereof by means of X-ray diffractometry is presented in FIG. 1b.

[0044] The data of the .sup.29Si NMR spectroscopy analysis:

[0045] .sup.29Si NMR (99.4 MHz, CD.sub.2Cl.sub.2, 298 K): δ=7.2 ppm.