EP0899779A2
Expired / Lapsed
EP
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Method for fabricating thermally stable contacts
Assignee: Texas Instruments Inc
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Filing: 1998-08-28
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Granted: —
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Expires: 2018-08-28
Abstract
Abstract In order to provide a thermally stable diffusion barrier for a contact, a layer of titanium (11) is formed on the patterned substrate (10). A layer of tungsten nitride (12) is formed on the titanium layer (11). After an annealing step, an interfacial layer (11') and a layer of titanium nitride (12') are formed between the substrate (10) and a tungsten layer (13'). These layers provide a diffusion barrier which is more thermally stable than a titanium nitride layer applied directly on the substrate and which permits the formation of a contact structures that can withstand subsequent high temperature steps.
Inventors
- 👤 Jiong-Ping Lu
- 👤 Chih-Chen Cho
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 01:08
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/047; C; C23; C23C; C23C16/00; C23C16/06; C23C16/08; C23C16/16; H10W20/033; Y; Y10; Y10S; Y10S438/00; Y10S438/927
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
44 words
A method of forming a diffusion barrier layer for a
contact structure, said method comprising the steps of: forming a layer of titanium on a patterned substrate; forming a layer of tungsten nitride on said titanium
layer; annealing said layers along with said substrate.
Claim 2
Dependent Claim
21 words
The method of claim 1 wherein titanium is replaced by an
element selected from the group consisting of cobalt and nickel.
Claim 3
Dependent Claim
36 words
The method of claim 1 wherein said titanium layer is
replaced by an MSi x layer or MSi x /M layers, wherein M is a metal
selected from the group consisting of titanium, cobalt and nickel.
Claim 4
Dependent Claim
42 words
The method of claim 1 wherein said titanium layer is
formed using a CVD process based on the chemical process TiX 4 + H 2 → Ti + HX, where X is selected from the group consisting of chlorine, bromine
and iodine.
Claim 5
Dependent Claim
70 words
The method of claim 1 wherein said tungsten nitride layer
is formed using CVD process based on a chemical process selected
from the group of chemical processes consisting of: WF 6 + NH 3 + H 2 → WN x + HF, WF 6 + N 2 + H 2 → WN x + HF, and W(CO) 6 + NH 3 → WN x + CO + H 2 .
Claim 6
Independent Claim
49 words
A method for forming a contact structure, said method
comprising the steps of: forming a titanium layer on a substrate; forming a tungsten nitride layer on said titanium
layer; forming a tungsten layer on said tungsten nitride
layer; and annealing the structure resulting from a formation of
these layers.
Claim 7
Dependent Claim
21 words
The method of claim 8 wherein titanium is replaced by an
element selected from the group consisting of cobalt and nickel.
Claim 8
Dependent Claim
38 words
The method of claim 8 wherein said titanium layer is
replaced by a one of an MSi x layer or a MSi x /M layers, where M is
selected from the group consisting of titanium, cobalt, or nickel.
Claim 9
Dependent Claim
45 words
The method of claim 8 wherein said titanium layer is
formed using a CVD process based on the chemical process TiX 4 + H 2 → Ti + HX, wherein X is selected from the group consisting of chorine (Cl),
bromine (Br), and iodine (I).
Claim 10
Dependent Claim
69 words
The method of claim 8 wherein said tungsten nitride
layer is formed using CVD process based on a chemical process
selected from the group of chemical processes consisting of: WF 6 + NH 3 + H 2 → WN x + HF, WF 6 + N 2 + H 2 → WN x +HF, and W(CO) 6 + NH 3 → WN x + CO + H 2 .
References Cited (Backward Citations)
No citation records indexed.
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