Patent EP0591086A2 successfully refreshed from Google Patents.
EP0591086A2
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EP
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Low temperature chemical vapor deposition and method for depositing a tungsten silicide film with improved uniformity and reduced fluorine concentration
Assignee: International Business Machines Corp
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Filing: 1993-09-10
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Granted: —
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Expires: 2013-09-10
Abstract
Abstract A tungsten silicide (WSix) film is formed by chemical vapor deposition using the reduction of tungsten hexafluoride (WF6) with dichlorosilane (SiH2Cl2) referred to as DCS and a reducing agent comprising silane (SiH4), hydrogen, or a mixture thereof. According to the method of the present invention, the WSix film is formed in a CVD reactor operating at a low pressure and at a wafer temperature between about 300 and 550°C. In the preferred embodiment, a thin nucleation layer is deposited before the WSix film. The deposited WSix films exhibit low flourine concentrations with good within-wafer uniformity and process stability. The attached plot illustrates a comparison the growth rates (given as the weight in mg per deposition time in Min) versus the wafer temperature in °C, using DCS (curve 10), DCS + SiH₄ (curve 12) and DCS + H2 (curve 14).
Inventors
- 👤 Thomas Richard Gow
- 👤 Richard John Lebel
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 14:42
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/22; C23C16/30; C23C16/42; C23C16/02; C23C16/0272; H; H10; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01304; H10D64/01306; H10D64/01308; H10D64/01312; H10P; H10P14/00; H10P14/40; H10P14/42; H10P14/43
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
57 words
A method for forming a metal silicide film on a semiconductor wafer placed in a reaction chamber comprising the steps of: supplying a gas mixture comprising a metal halide, dichlorosilane, and a reducing agent to said reaction chamber, said reducing agent comprising silane, hydrogen, or a mixture thereof; and depositing said metal silicide film on said wafer.
Claim 2
Dependent Claim
19 words
The method of claim 1 further comprising the step of maintaining the temperature of said wafer below about 550°C.
Claim 3
Dependent Claim
21 words
The method of claim 1 further comprising the step of maintaining the pressure of said reaction chamber below about one torr.
Claim 4
Dependent Claim
27 words
The method of claim 1 further comprising the steps of: providing a susceptor within said reaction chamber; and maintaining the temperature of said susceptor below about 650°C.
Claim 5
Dependent Claim
20 words
The method of claim 1 further comprising the step of maintaining the temperature of said wafer substantially below about 400°C.
Claim 6
Dependent Claim
27 words
The method of claim 1 further comprising the step of maintaining the proportion of silane in said gas mixture below about 50% by volume relative to dichlorosilane.
Claim 7
Dependent Claim
29 words
The method of claim 1 further comprising the step of maintaining the proportion of hydrogen in said gas mixture between about 20 to 100% by volume relative to dichlorosilane.
Claim 8
Independent Claim
55 words
A method for fabricating a semiconductor device comprising the steps of: providing a reaction chamber; providing a semiconductor wafer having a surface; placing said wafer in said reaction chamber; supplying a gas mixture comprising tungsten hexafluoride, dichlorosilane, and silane to said reaction chamber; and depositing a tungsten silicide film on said surface of said wafer.
Claim 9
Dependent Claim
21 words
The method of claim 8 further comprising the step of maintaining the temperature of said wafer between about 300 to 550°C.
Claim 10
Dependent Claim
23 words
The method of claim 8 further comprising the step of maintaining the pressure of said reaction chamber between about 250 to 400 mtorr.
Claim 11
Dependent Claim
29 words
The method of claim 8 further comprising the steps of: providing a susceptor within said reaction chamber; and maintaining the temperature of said susceptor between about 400 to 600°C.
Claim 12
Dependent Claim
20 words
The method of claim 8 further comprising the step of maintaining the temperature of said wafer substantially below about 400°C.
Claim 13
Dependent Claim
20 words
The method of claim 8 wherein the proportion of silane in said gas mixture is between about 0.5 to 10%.
Claim 14
Dependent Claim
21 words
The method of claim 8 wherein the step of providing a reaction chamber comprises providing a cold-wall chemical vapor deposition reactor.
Claim 15
Independent Claim
55 words
A method for fabricating a semiconductor device comprising the steps of: providing a reaction chamber; providing a semiconductor wafer having a surface; placing said wafer in said reaction chamber; supplying a gas mixture comprising tungsten hexaflouride, dichlorosilane, and hydrogen to said reaction chamber; and depositing a tungsten silicide film on said surface of said wafer.
Claim 16
Dependent Claim
21 words
The method of claim 15 further comprising the step of maintaining the temperature of said wafer between about 300 to 550°C.
Claim 17
Dependent Claim
23 words
The method of claim 15 further comprising the step of maintaining the pressure of said reaction chamber between about 250 to 400 mtorr.
Claim 18
Dependent Claim
29 words
The method of claim 15 further comprising the steps of: providing a susceptor within said reaction chamber; and maintaining the temperature of said susceptor between about 400 to 600°C.
Claim 19
Dependent Claim
20 words
The method of claim 15 further comprising the step of maintaining the temperature of said wafer substantially below about 400°C.
Claim 20
Dependent Claim
25 words
The method of claim 15 wherein the proportion of hydrogen in said gas mixture is between about 50 to 90% by volume relative to dichlorosilane.
Claim 21
Dependent Claim
21 words
The method of claim 15 wherein the step of providing a reaction chamber comprises providing a cold-wall chemical vapor deposition reactor.
Claim 22
Independent Claim
55 words
A method for forming a tungsten silicide film on a semiconductor wafer in a reaction chamber comprising the steps of: supplying a gas mixture comprising tungsten hexaflouride, dichlorosilane, and a reducing agent to said reaction chamber, said reducing agent comprising silane, hydrogen, or a mixture thereof; and depositing said tungsten silicide film on said wafer.
Claim 23
Dependent Claim
31 words
The method of claim 22 further comprising the step of increasing the proportion of hydrogen relative to dichlorosilane in said gas mixture to decrease the resistivity of said tungsten silicide film.
Claim 24
Dependent Claim
31 words
The method of claim 22 further comprising the step of increasing the proportion of silane relative to dichlorosilane in said gas mixture to increase the resistivity of said tungsten silicide film.
Claim 25
Independent Claim
101 words
A method for forming a tungsten silicide film on a semiconductor wafer in a reaction chamber comprising the steps of: supplying a first gas mixture comprising tungsten hexaflouride, dichlorosilane, and a reducing agent to said reaction chamber, said reducing agent comprising silane, hydrogen, or a mixture thereof; depositing a nucleation layer on said wafer for a first time period; supplying a second gas mixture comprising tungsten hexaflouride, dichlorosilane, and a reducing agent to said reaction chamber, said reducing agent comprising silane, hydrogen, or a mixture thereof; and depositing said tungsten silicide film overlying said nucleation layer for a second time period.
Claim 26
Dependent Claim
27 words
The method of claim 25 wherein the proportion of tungsten hexaflouride relative to dichlorosilane in said second gas mixture is greater than in said first gas mixture.
Claim 27
Dependent Claim
23 words
The method of claim 25 wherein the duration of said first time period is less than the duration of said second time period.
Claim 28
Dependent Claim
12 words
The method of claim 25 wherein said nucleation layer comprises tungsten silicide.
Claim 29
Dependent Claim
18 words
The method of claim 25 wherein said second time period follows said first time period without substantial delay.
Claim 30
Dependent Claim
26 words
The method of claim 25 wherein the proportion of silane relative to dichlorosilane in said first gas mixture is greater than in said second gas mixture.
Claim 31
Dependent Claim
27 words
The method of claim 30 wherein the proportion of tungsten hexaflouride relative to dichlorosilane in said second gas mixture is greater than in said first gas mixture.
Claim 32
Dependent Claim
16 words
The method of claim 25 wherein said second time period is less than about 500 seconds.
Claim 33
Dependent Claim
17 words
The method of claim 32 wherein said first time period is between about 30 to 60 seconds.
Claim 34
Dependent Claim
19 words
The method of claim 25 further comprising the step of maintaining the temperature of said wafer below about 550°C.
References Cited (Backward Citations)
No citation records indexed.
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