EP0772231A2
Expired / Lapsed
EP
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A method of forming a low stress polycide conductors on a semiconductor chip
Assignee: International Business Machines Corp
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Filing: 1996-10-21
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Granted: —
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Expires: 2016-10-21
Abstract
Abstract A method of forming low resistivity conductive lines on a semiconductor substrate is disclosed. In practicing the method a multichamber tool is used to advantage by forming a first doped polysilicon layer on the surface of a substrate, forming a second undoped layer on the doped layer, while maintaining the work piece under a vacuum environment, moving the substrate to a second chamber and thereafter forming a silicide containing layer on the undoped polysilicon layer. various techniques may be used to deposit either the polysilicon or the silicide layer such as sputtering may also be used. Practice of the method eliminates separation of silicide from polysilicon and increases product yield.
Inventors
- 👤 Anthony Kendall Stamper
- 👤 Richard John Lebel
- 👤 Gary Lionel Langdeau
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 14:31
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/064; H10W20/066; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0112; H10D64/013; H10D64/01302; H10D64/01304; H10D64/01306; H10D64/01308; H10D64/01312
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
124 words
The method of forming a conductive line on the surface of a semiconductor substrate comprising the steps of: a) providing a deposition environment including a tool having a plurality of adjacent deposition chambers; b) placing a semiconductor substrate within a first deposition chamber; c) depositing a doped polycrystalline silicon layer on the surface of the substrate; d) depositing an undoped layer of polycrystalline silicon on the doped layer; e) maintaining the substrate in a chemically inactive environment; f) moving the substrate from the first chamber to a second chamber within the tool while maintaining the substrate in said chemically inactive environment and preventing the substrate from being exposed to a chemically active environment; g) forming a conductive silicide layer on the undoped polycrystalline layer.
Claim 2
Dependent Claim
30 words
The method of claim 1 wherein: said doped polycrystalline layer is formed by exposing said substrate simultaneously to silane and phosphorus gases; and maintaining said substrate at about 650° Celsius.
Claim 3
Independent Claim
43 words
The method of any preceding claim wherein there is further provided the step of shutting off said phosphorus gas after a selected period of time; and maintaining said substrate in said silane gas for an additional period to form said undoped polycrystalline layer.
Claim 4
Independent Claim
38 words
The method of any preceding claim wherein said silicided layer is formed by coating said substrate, coated with a dual layer doped and undoped polycrystalline silicon layer, with either chemical vapor deposited or physical vapor deposited tungsten silicide.
Claim 5
Dependent Claim
28 words
The method of claim 4 wherein the substrate, coated with a dual layer of doped and undoped polycrystalline silicon layer is exposed to gaseous dichlorosilane and tungsten hexafluoride.
Claim 6
Dependent Claim
29 words
The method of claim 4 wherein the substrate, coated with a dual layer of doped and undoped polycrystalline, is exposed to an atmosphere of argon and sputtered tungsten silicide.
Claim 7
Independent Claim
98 words
The method of any preceding claim wherein the chambers in said tool are heated to about 650° Celsius; said doped polycrystalline layer is formed by the steps of: establishing the pressure in said first chamber at about 80 Torr; exposing said substrate simultaneously to about 500 SCCM of silane and about 50 SCCM of phosphine for a period of about 120 seconds to form polycrystalline silicon doped with phosphorus to a density of approximately 3 X 10 20 phosphorus atoms/cm 3 ; shutting off the phosphine gas after said 120 seconds and continuing silane flow for 15 seconds.
Claim 8
Independent Claim
93 words
The method of any preceding claim wherein: the conductive silicide is formed by exposing said substrate in said second chamber to a flow of about 175 SCCM of gaseous dichlorosilane and a flow of about 3.5 SCCM of tungsten hexafluoride for a period of about 133 seconds; shutting off the tungsten hexafluoride after said about 133 seconds; and there is further provided the step of: passivating the formed silicide by maintaining the about 175 SCCM flow of the gaseous dichlorosilane for an additional about 25 seconds after said tungsten hexaflouride is shut off.
References Cited (Backward Citations)
No citation records indexed.
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