EP0397131A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of manufacturing a contact in semiconductor devices
Assignee: Fujitsu Ltd
•
Filing: 1990-05-09
•
Granted: —
•
Expires: 2010-05-09
Abstract
Abstract A method of forming a contact in a semiconductor device involving cleaning the surface of a substrate exposed in a contact hole, formed for example through an SiO₂ film on the substrate, using the reducing effect of a nitrogen hydride or nitrogen hydride derivative gas, for example N₂H₄ gas. Thereafter, for example, a TiN barrier may be formed by a CVD method using a mixed gas of N₂H₄ and TiCl₄ (the surface not being exposed to air) and then a tungsten contact layer formed thereon by a CVD method using a mixed gas of N₂H₄ and WF₆. Alternatively, a TiN layer may be formed by a CVD method on a tungsten contact layer formed by a CVD method direct on the substrate.
Inventors
- 👤 Takayuki C/O Fujitsu Limited Patent Dept. Ohba
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 19:27
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/20; H10P70/23; H10P70/234; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033; H10W20/056; H10W20/057; H10W20/071; H10W20/081
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
48 words
A method of manufacturing a contact on a substrate surface, including cleaning an exposed surface region of the substrate, which exposed surface region may be that of a semiconductor or conductor material of the substrate structure, using a gas comprising a nitrogen hydride or a nitrogen hydride derivative.
Claim 2
Independent Claim
48 words
A method of manufacturing a contact on a substrate surface, including cleaning an exposed surface region of the substrate, which exposed surface region may be that of a semiconductor or conductor material of the substrate structure, using a gas comprising a nitrogen hydride or a nitrogen hydride derivative.
Claim 3
Independent Claim
60 words
A method of manufacturing a contact on a substrate surface, which surface may be that of a semiconductor or conductor material of the substrate structure, including forming a conducting material layer containing a metal on the substrate using a gas mixture containing a gas comprising a nitrogen hydride or a nitrogen hydride derivative and a gas comprising a metal compound.
Claim 4
Independent Claim
60 words
A method of manufacturing a contact on a substrate surface, which surface may be that of a semiconductor or conductor material of the substrate structure, including forming a conducting material layer containing a metal on the substrate using a gas mixture containing a gas comprising a nitrogen hydride or a nitrogen hydride derivative and a gas comprising a metal compound.
Claim 5
Dependent Claim
26 words
A method as claimed in claim 1, wherein the cleaning is performed at a temperature such that nitrogenation of the exposed substrate region is substantially avoided.
Claim 6
Dependent Claim
22 words
A method as claimed in claim 3, wherein the said temperature is between 200°C and 900°C, and preferably between 300°C and 600°C.
Claim 7
Dependent Claim
15 words
A method as claimed in claim 2, wherein the so-formed conducting material layer contains nitrogen.
Claim 8
Dependent Claim
30 words
A method as claimed in claim 2, wherein the forming of the conducting material layer is effected a temperature lower than 600°C, such that metal is deposited on the substrate.
Claim 9
Dependent Claim
39 words
A method as claimed in claim 5, wherein the forming of the conducting material layer is effected at a temperature preferably between 300°C and 700°C, or higher than 400°C, such that metal containing nitrogen is deposited on the substrate.
Claim 10
Dependent Claim
45 words
A method as claimed in claim 2, 5, 6, or 7, wherein a further conducting material layer containing a metal is formed using a gas mixture containing a gas comprising a nitrogen hydride or a nitrogen hydride derivative and a gas comprising a metal compound.
Claim 11
Dependent Claim
32 words
A method as claimed in claim 2, 5, 6, 7 or 8, performed after cleaning as claimed in claim 1, 3 or 4, without intermediate exposure of the substrate to atmospheric conditions.
Claim 12
Dependent Claim
28 words
A method as claimed in claim 9, wherein cleaning and the formations of the conducting material layers are effected successively without exposure of the substrate to atmospheric conditions.
Claim 13
Dependent Claim
24 words
A method as claimed in claim 10, wherein cleaning and the formations of the conducting material layers are performed in the same gas chamber.
Claim 14
Dependent Claim
29 words
A method as claimed in claim 10, wherein cleaning and the formations of the conducting material layers are performed successively in different gas chambers, connected through a connecting chamber.
Claim 15
Dependent Claim
42 words
A method as claimed in claim 2, or any one of claims 5 to 12, wherein said metal is selected from the group consisting of tungsten (W), titanium (Ti), molybdenum (Mo), vanadium (V), zirconium (Zr), gold (Au), copper (Cu), and platinum (Pt).
Claim 16
Dependent Claim
26 words
A method as claimed in claim 2, or any one of claims 5 to 13, wherein said gas comprising a metal compound is a metal halide.
Claim 17
Dependent Claim
34 words
A method as claimed in claim 14, wherein said metal halide is selected from the group consisting of tungsten hexafluoride (WF₆), titanium tetrachloride (TiCl₄) and halides of Mo, V, Zr, Au, Cu and Pt.
Claim 18
Dependent Claim
26 words
A method as claimed in claim 2, or any one of claims 5 to 13, wherein said gas comprising a metal compound is a metal complex.
Claim 19
Dependent Claim
33 words
A method as claimed in claim 16, wherein said metal complex is selected from the group consisting of tungsten carbonyl (W(Co)₆), copper hexafluoroacetylacetone (Cu(HFA)₂), gold hexafluoroacetylacetone (Au(HFA)) and complexes of Ti and Zr.
Claim 20
Independent Claim
27 words
A method as claimed in any preceding claim, wherein each molecule of the nitrogen hydride or the nitrogen hydride derivative employed contains more than two nitrogen atoms.
Claim 21
Independent Claim
21 words
A method as claimed in any one of claims 1 to 17, wherein hydrazine (N₂H₄) is used as the nitrogen hydride.
Claim 22
Independent Claim
27 words
A method as claimed in any one of claims 1 to 17, wherein dimethyl hydrazine (CH₃)₂N₂H₂ or monomethyl hydrazine (CH₃)N₂H₃ is used as the nitrogen hydride derivative.
Claim 23
Independent Claim
16 words
A method as claimed in any preceding claim, wherein the substrate has a base of silicon.
Claim 24
Independent Claim
24 words
A method as claimed in any preceding claim, wherein a region of the substrate is exposed through an insulating layer formed on the substrate.
Claim 25
Independent Claim
269 words
A method as claimed in claims 11 or 12, said method comprising the steps of:- (a) cleaning an exposed surface region of a silicon substrate at the bottom of a contact hole formed in a silicon dioxide film on said silicon substrate, said silicon substrate being heated at a temperature between 200 and 900°C, more preferably 300°C, using a mixed gas of hydrazine at a flow of 10 SCCM and hydrogen at a flow of 10 SCCM; (b) forming a tungsten (W) layer on said exposed surface region of the silicon substrate at the bottom of said contact hole at about 300°C by CVD (chemical vapour deposition), using a mixed gas of WF₆ at a flow of 15 SCCM, N₂H₄ at 10 SCCM and H₂ at 50 SCCM; (c) forming a TiN layer on said tungsten (W) layer at a temperature between 500 and 600°C, preferably at about 600°C, by CVD using a mixed gas of TiCl₄ at a flow of 10 SCCM, N₂H₄ at 10 SCCM and H₂ at 50 SCCM; (d) patterning a further tungsten (W) layer under atmospheric conditions, which further tungsten (W) layer is formed on said TiN layer under the same conditions as those of step (b); (e) cleaning an exposed surface region of the further tungsten (W) layer at the bottom of a contact hole formed in a silicon dioxide film formed on the further tungsten (W) layer, under the same conditions as those of step (a); and (f) forming a tungsten (W) layer on said exposed surface region at the bottom of said contact hole, under the same conditions of step (b).
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.