CN100358105C

CN100358105C - Method for preparing Poly-SiGe film

Info

Publication number: CN100358105C
Application number: CNB2005100605664A
Authority: CN
Inventors: 叶志镇; 吴贵斌; 赵星; 刘国军
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2005-08-30
Filing date: 2005-08-30
Publication date: 2007-12-26
Anticipated expiration: 2025-08-30
Also published as: CN1731561A

Abstract

The present invention discloses a method for preparing polycrystalline germanium silicon films, which has the procedures that a silicon substrate is put into a thermal oxidation stove after cleaned; a silicon dioxide layer is in thermal oxidation on the silicon substrate; then a layer of metallic nickel or metallic cobalt is steamed and coated on silicon wafers after the thermal oxidation by using electron beam evaporation; next, samples coated with the nickel or the cobalt are put into a superhigh vacuum chemical gas phase deposition device. A pure silicon source is introduced into the superhigh vacuum chemical gas phase deposition device in the temperature of 500 to 600 DEG C; the pressure intensity of a growth room is controlled within 20 pa; the samples coated with the nickel or the cobalt grow; the nickel or the cobalt is transformed into nickel silicides or cobalt silicides, and an air source is transformed into pure silane and germane which uses hydrogen gas as supporting gas; a layer of polycrystalline germanium silicon film is formed on the nickel silicide or the cobalt silicide. The polycrystalline germanium silicon film prepared by using the method effectively reduces metal pollution, and needs no anneal crystallization because metal induced and film growth are carried out almost simultaneously. Thus, the present invention provides high quality polycrystalline germanium silicon films for semiconductor device manufacture.

Description

A kind of preparation method of poly-SiGe film

Technical field

The present invention relates to the preparation of semi-conducting material, is the preparation method about poly-SiGe film specifically.

Background technology

Poly-SiGe film is because have higher mobility, and energy gap can be regulated continuously with the variation of germanium component, and manufacturing cost is lower, thereby is with a wide range of applications.Present preparation poly-SiGe film promptly at first passes through for example ion beam sputtering elder generation's growth amorphous germanium silicon on substrate of physical method based on the solid-phase crystallization technology, utilizes long term annealing realization crystallization under the uniform temperature again; In order to shorten annealing time, the method for present more employing is a crystallization inducing metal, and this method interacts by metal and noncrystal membrane in amorphous germanium silicon film surface evaporation layer of metal, and amorphous is converted into polycrystalline.Though this method can realize rapid crystallization,, influence the performance of back device because there is comparatively serious metallic pollution in the diffusion of metal in amorphous.

Summary of the invention

The preparation method who the purpose of this invention is to provide a kind of poly-SiGe film thinks that the semiconductor device manufacturing provides high-quality poly-SiGe film.

The manufacture method of poly-SiGe film of the present invention may further comprise the steps:

1) puts into thermal oxidation furnace after silicon substrate is cleaned up, feed pure oxygen in the silicon dioxide layer of 900～1200 ℃ of following thermal oxidation one deck 0.2～0.3 μ m;

2) utilizing electron beam evaporation evaporation one bed thickness on the silicon chip after the thermal oxidation is metallic nickel or the metallic cobalt of 30～60nm;

3) sample of Ni plated or cobalt is put into the high vacuum chemical vapor phase growing apparatus, under 500～600 ℃, feed the pure silicon source earlier, the control growing constant pressure is strong＜20Pa, grow, make nickel or cobalt be converted into nickel or cobalt silicide, again source of the gas is converted to pure silane and is the germane of carrier gas with hydrogen, the volume content of germane is 10% of germane and the mixed gas of hydrogen, pure silane is 5: 5 with the flow-rate ratio of germane and the mixed gas of hydrogen, grew 40～60 minutes, and on nickel or cobalt silicide, formed one deck poly-SiGe film.

Above-mentioned silicon source can be the silane or the disilane of purity＞99.999%; The purity of oxygen source＞99.99%.

The method for preparing poly-SiGe film of the present invention, because before the poly-SiGe film deposition, metallic nickel or cobalt generate nickel or cobalt silicide with the silicon atom reaction earlier, carrying out along with reaction, nickel or cobalt constantly are consumed, be transformed into nickel or cobalt silicide fully until nickel or cobalt, thereby this method can effectively reduce the pollution of metal; On the other hand owing to be easy to heterogeneous growth poly-SiGe film on nickel or cobalt silicide, so metal inducement and film growth almost carry out simultaneously, need not annealing crystallization.Thereby can provide high-quality poly-SiGe film for the semiconductor device manufacturing.

Embodiment

Further specify the present invention below in conjunction with instantiation.

Implement 1

The preparation method of poly-SiGe film, step is as follows:

1) puts into thermal oxidation furnace after silicon substrate is cleaned up, feed purity and be 99.99% oxygen in the silicon dioxide layer of 1000 ℃ of following thermal oxidation one deck 0.2 μ m;

2) resulting product is put into evaporation equipment, evaporation one bed thickness is the metallic nickel of 30nm on the silicon chip after the thermal oxidation;

3) sample of Ni plated is put into the high vacuum chemical vapor phase growing apparatus, under 530 ℃, feeding purity is 99.999% silane earlier, and the strong 10Pa of control growing constant pressure grew 20 minutes, make nickel be converted into nickel silicide, source of the gas is converted to pure silane again and is the germane of carrier gas with hydrogen, the volume content of germane is 10% of germane and the mixed gas of hydrogen, and pure silane is 5: 5 with germane with the flow-rate ratio that hydrogen mixes gas, grew 40 minutes, and on nickel silicide, formed one deck poly-SiGe film.

Implement 2

The preparation method of poly-SiGe film, step is as follows:

1) puts into thermal oxidation furnace after silicon substrate is cleaned up, feed purity and be 99.99% oxygen in the silicon dioxide layer of 1100 ℃ of following thermal oxidation one deck 0.3 μ m;

2) resulting product is put into evaporation equipment, evaporation one bed thickness is the metallic cobalt of 60nm on the silicon chip after the thermal oxidation;

3) sample that will plate cobalt is put into the high vacuum chemical vapor phase growing apparatus, under 600 ℃, feeding purity is 99.999% disilane earlier, the strong 10Pa of control growing constant pressure, grew 30 minutes, make cobalt be converted into cobalt silicide, again source of the gas is converted to pure disilane and is the germane of carrier gas with hydrogen, the volume content of germane is 10% of germane and the mixed gas of hydrogen, pure disilane is 5: 5 with the flow-rate ratio of germane and the mixed gas of hydrogen, grew 40 minutes, and on cobalt silicide, formed one deck poly-SiGe film.

Claims

1. the preparation method of a poly-SiGe film, its step is as follows:

2. the preparation method of poly-SiGe film according to claim 1 is characterized in that said silicon source is the silane or the disilane of purity＞99.999%.

3. the preparation method of poly-SiGe film according to claim 1 is characterized in that purity＞99.99% of oxygen source.