US5393565A
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Method for deposition of a refractory metal nitride and method for formation of a conductive film containing a refractory metal nitride
Assignee: Fujitsu Semiconductor Ltd
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Filing: 1993-06-07
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Granted: 1995-02-28
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Expires: 2013-06-07
Abstract
Abstract A refractory metal nitride is deposited at a temperature of 600° C. according to a chemical vapor phase deposition method by using a source gas containing a refractory metallic element and a reduction gas containing one of an alkyl amino compound, alkyl azide compound, hydrazine and a hydrazine alkyl compound for reducing the source gas. This refractory metal nitride is used as a barrier metal material for interconnection in a semiconductor device. When forming a refractory metal nitride as a barrier metal on a silicon layer or forming a contact metal between the barrier metal and the silicon layer, a natural oxide film on the surface of the silicon layer set in a pressure-reduced atmosphere is removed by reducing with hydrazine or a hydrazine alkyl compound.
Inventors
- 👤 Toshiya Suzuki
- 👤 Takayuki Ohba
- 👤 Shimpei Jinnouchi
- 👤 Seishi Murakami
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:14
CPC Classifications
C; C23; C23C; C23C16/00; H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/047; C23C16/22; C23C16/30; C23C16/34; H10W20/033
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
61 words
A method for deposition of a refractory metal nitride, wherein a refractory metal nitride is deposited in a vapor phase by using a source gas containing a refractory metal and a reducing and nitrogenizing gas containing at least one of an alkyl amino compound, an alkyl azide compound, hydrazine and a hydrazine alkyl compound for reducing and nitrogenizing said source gas.
Claim 2
Independent Claim
61 words
A method for deposition of a refractory metal nitride, wherein a refractory metal nitride is deposited in a vapor phase by using a source gas containing a refractory metal and a reducing and nitrogenizing gas containing at least one of an alkyl amino compound, an alkyl azide compound, hydrazine and a hydrazine alkyl compound for reducing and nitrogenizing said source gas.
Claim 3
Dependent Claim
29 words
A method for deposition of a refractory metal nitride in accordance with claim 1, wherein said refractory metal nitride is one of titanium nitride, tungsten nitride and molybdenum nitride.
Claim 4
Dependent Claim
23 words
A method for deposition of a refractory metal nitride in accordance with claim 1, wherein said reducing and nitrogenizing gas additionally contains ammonia.
Claim 5
Dependent Claim
49 words
A method for deposition of a refractory metal nitride in accordance with claim 1, wherein said source gas contains one of a halide of a refractory metal, an alkyl amino compound of a refractory metal, art alkoxide of a refractory metal and a cyclopentadienyl compound of a refractory metal.
Claim 6
Dependent Claim
32 words
A method for deposition of a refractory metal nitride in accordance with claim 1, wherein the content of the refractory metal in said refractory metal nitride is at least 60 atomic %.
Claim 7
Independent Claim
132 words
A method for forming a conductive film which has a refractory metal nitride layer, said method comprising: (a) depositing a refractory metal nitride film containing at least 60 atomic % of a refractory metal on an upper surface of a silicon layer by a chemical vapor deposition method, the refractory metal nitride film being deposited by using a reduction gas containing at least one of an alkyl amino compound, hydrazine and a hydrazine alkyl compound; (b) forming a refractory metal silicide layer between said refractory metal nitride film and said silicon layer by heating said refractory metal nitride film at a temperature of at least 450° C.; and (c) forming a conductive film which provides a lower resistance than that of said refractory metal nitride film on said refractory metal nitride film.
Claim 8
Independent Claim
132 words
A method for forming a conductive film which has a refractory metal nitride layer, said method comprising: (a) depositing a refractory metal nitride film containing at least 60 atomic % of a refractory metal on an upper surface of a silicon layer by a chemical vapor deposition method, the refractory metal nitride film being deposited by using a reduction gas containing at least one of an alkyl amino compound, hydrazine and a hydrazine alkyl compound; (b) forming a refractory metal silicide layer between said refractory metal nitride film and said silicon layer by heating said refractory metal nitride film at a temperature of at least 450° C.; and (c) forming a conductive film which provides a lower resistance than that of said refractory metal nitride film on said refractory metal nitride film.
Claim 9
Dependent Claim
41 words
A method for forming a conductive film which has a refractory metal nitride layer in accordance with claim 6, wherein said refractory metal nitride film is one of a titanium nitride film, a tungsten nitride film and a molybdenum nitride film.
Claim 10
Dependent Claim
81 words
A method for forming a conductive film which has a refractory metal nitride layer in accordance with claim 6, further comprising: before step (a), maintaining said silicon layer in a pressure-reduced atmosphere; and before step (a), removing a natural oxide film from the surface of said silicon layer through a thermal chemical reaction by introducing a reduction gas containing at least one of hydrazine and a hydrazine alkyl compound onto the surface of said silicon layer maintained in the pressure-reduced atmosphere.
Claim 11
Dependent Claim
43 words
A method for forming a conductive film which has a refractory metal nitride layer in accordance with claim 8, wherein maintaining said silicon layer in a pressure-reduced atmosphere, removing a natural oxide film and step (a) are carried out in a pressure-reduced atmosphere.
Claim 12
Independent Claim
137 words
A method for forming a conductive film having a refractory metal nitride layer, said method comprising: (a) forming a refractory metal silicide layer according to a vapor deposition method by supplying a mixed gas containing one of hydrazine gas, a hydrazine alkyl compound gas and an alkyl amino compound gas, a gas containing a refractory metallic element and a polysilane gas onto a silicon layer; (b) forming a refractory metal nitride film according to a vapor deposition method by supplying a mixed gas containing one of hydrazine gas, a hydrazine alkyl compound gas and an alkyl amino compound gas, and a gas containing a refractory metallic element onto said refractory metal silicide layer; and (c) forming a conductive film having a lower resistance than that of said refractory metal nitride film on said refractory metal nitride film.
Claim 13
Independent Claim
137 words
A method for forming a conductive film having a refractory metal nitride layer, said method comprising: (a) forming a refractory metal silicide layer according to a vapor deposition method by supplying a mixed gas containing one of hydrazine gas, a hydrazine alkyl compound gas and an alkyl amino compound gas, a gas containing a refractory metallic element and a polysilane gas onto a silicon layer; (b) forming a refractory metal nitride film according to a vapor deposition method by supplying a mixed gas containing one of hydrazine gas, a hydrazine alkyl compound gas and an alkyl amino compound gas, and a gas containing a refractory metallic element onto said refractory metal silicide layer; and (c) forming a conductive film having a lower resistance than that of said refractory metal nitride film on said refractory metal nitride film.
Claim 14
Dependent Claim
40 words
A method for forming a conductive film having a refractory metal nitride layer in accordance with claim 10, wherein said refractory metal nitride film is one of a titanium nitride film, a tungsten nitride film and a molybdenum nitride film.
Claim 15
Dependent Claim
80 words
A method for forming a conductive film having a refractory metal nitride layer in accordance with claim 10, further comprising: before step (a), maintaining said silicon layer in a pressure-reduced atmosphere; and before step (a), removing a natural oxide film from the surface of said silicon layer through a thermal chemical reaction by introducing a reduction gas containing at least one of hydrazine and a hydrazine alkyl compound onto the surface of said silicon layer maintained in the pressure-reduced atmosphere.
Claim 16
Dependent Claim
42 words
A method for forming a conductive film having a refractory metal nitride layer in accordance with claim 12, wherein maintaining said silicon layer in a pressure-reduced atmosphere, removing a natural oxide film and step (a) are carried out in a pressure-reduced atmosphere.
Claim 17
Dependent Claim
57 words
A method for forming a conductive film having a refractory metal nitride layer in accordance with claim 10, wherein the gas containing said refractory metallic element is one of a halide of a refractory metal, an alkyl amino compound of a refractory metal, an alkoxide of a refractory metal and a cyclopentadienyl compound of a refractory metal.
References Cited (Backward Citations)
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