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US5496762A Expired / Lapsed US ⏱️ 0.0 years remaining

Highly resistive structures for integrated circuits and method of manufacturing the same

Assignee: Micron Technology Inc
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Filing: 1994-06-02
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Granted: 1996-03-05
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Expires: 2014-06-02
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Abstract

Abstract This invention is a process for making resistor structures having high stability and reliability characteristics. Process parameters are easily modifiable to adjust the resistivity of the structures. A layer of titanium nitride, which may contain certain impurities such as carbon, is deposited via chemical vapor deposition by pyrolization of an organometallic precursor compound of the formula Ti(NR 2 ) 4 either alone or in the presence of either a nitrogen source (e.g. ammonia or nitrogen gas) or an activated species (which may include a halogen, NH 3 , or hydrogen radicals, or combinations thereof). The TiN film is then oxidized to create a structure that demonstrates highly stable, highly reliable resistive characteristics, with bulk resistivity values in giga ohm range. In a preferred embodiment of the invention, a predominantly amorphous titanium carbonitride film is deposited on an insulative substrate in a chemical vapor deposition chamber. A layer of titanium is then deposited on top of the titanium carbonitride film. The titanium layer is then patterned with photoresist. The exposed titanium is then etched with a reagent that is selective for titanium over titanium carbonitride (HF, for example, has better than 10:1 selectivity) so that the etch essentially stops when the titanium carbonitride film is exposed. The exposed titanium carbonitride film is then oxidized to achieve the desired resistivity.

Inventors

  • 👤 Gurtej S. Sandhu
  • 👤 Trung T. Doan
  • 👤 David A. Cathey

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 14:44
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/40; H10D1/47; H10D1/474; H10B; H10B10/00; H10B10/15; Y; Y10; Y10S; Y10S148/00; Y10S148/117; Y10S148/136

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 100 words
A process for manufacturing highly-resistive structures for use in integrated circuits, said process comprising the following sequence of steps: (a) forming an insulative layer on a semiconductor substrate; (b) depositing a predominantly amorphous titanium carbonitride layer on top of the insulative layer; (c) depositing a titanium layer on top of the titanium carbonitride layer; (d) masking the titanium layer so as to protect certain portions thereof and expose other portions thereof; (e) removing the exposed portions of the titanium layer so as to expose the underlying titanium carbonitride layer; and (f) oxidizing the exposed portions of the titanium carbonitride layer.
Claim 2
Dependent Claim 100 words
A process for manufacturing highly-resistive structures for use in integrated circuits, said process comprising the following sequence of steps: (a) forming an insulative layer on a semiconductor substrate; (b) depositing a predominantly amorphous titanium carbonitride layer on top of the insulative layer; (c) depositing a titanium layer on top of the titanium carbonitride layer; (d) masking the titanium layer so as to protect certain portions thereof and expose other portions thereof; (e) removing the exposed portions of the titanium layer so as to expose the underlying titanium carbonitride layer; and (f) oxidizing the exposed portions of the titanium carbonitride layer.
Claim 3
Dependent Claim 38 words
The process of claim 1, wherein the predominantly amorphous titanium carbonitride layer is deposited via chemical vapor deposition by pyrolization of an organometallic precursor compound of the formula Ti(NR 2 ) 4 wherein R is an alkyl group.
Claim 4
Dependent Claim 21 words
The process of claim 2, wherein pyrolization of the organometallic precursor compound takes place in the presence of a nitrogen source.
Claim 5
Dependent Claim 11 words
The process of claim 3, wherein said nitrogen source is ammonia.
Claim 6
Dependent Claim 12 words
The process of claim 3, wherein said nitrogen source is nitrogen gas.
Claim 7
Dependent Claim 33 words
The process of claim 2, wherein pyrolization of the organometallic precursor compound takes place in the presence of "at least one radical species derived from the group consisting of halogens, ammonia, and hydrogen".
Claim 8
Dependent Claim 20 words
The process of claim 1, wherein the exposed portions of the titanium layer are removed with a hydrofluoric acid etch.
Claim 9
Dependent Claim 27 words
The process of claim 1, wherein the exposed portions of the titanium layer are removed selectively with respect to the titanium carbonitride layer with a dry etch.
Claim 10
Dependent Claim 20 words
The process of claim 1, wherein the exposed portions of the titanium carbonitride layer are oxidized in an oxygen plasma.
Claim 11
Dependent Claim 22 words
The process of claim 1, wherein the exposed portions of the titanium carbonitride layer are oxidized by at least one oxidant gas.
Claim 12
Dependent Claim 91 words
A process for manufacturing highly-resistive structures for use in integrated circuits, said process comprising the following sequence of steps: (a) depositing a predominantly amorphous titanium carbonitride layer on top of an insulative layer; (b) depositing a titanium layer on top of the titanium nitride layer; (c) masking the titanium layer so as to protect certain portions thereof and expose other portions thereof; (d) removing the exposed portions of the titanium layer so as to expose the underlying titanium carbonitride layer; and (e) oxidizing the exposed portions of the titanium carbonitride layer.
Claim 13
Dependent Claim 91 words
A process for manufacturing highly-resistive structures for use in integrated circuits, said process comprising the following sequence of steps: (a) depositing a predominantly amorphous titanium carbonitride layer on top of an insulative layer; (b) depositing a titanium layer on top of the titanium nitride layer; (c) masking the titanium layer so as to protect certain portions thereof and expose other portions thereof; (d) removing the exposed portions of the titanium layer so as to expose the underlying titanium carbonitride layer; and (e) oxidizing the exposed portions of the titanium carbonitride layer.
Claim 14
Dependent Claim 38 words
The process of claim 11, wherein the predominantly amorphous titanium carbonitride layer is deposited via chemical vapor deposition by pyrolization of an organometallic precursor compound of the formula Ti(NR 2 ) 4 wherein R is an alkyl group.
Claim 15
Dependent Claim 21 words
The process of claim 12, wherein pyrolization of the organometallic precursor compound takes place in the presence of a nitrogen source.
Claim 16
Dependent Claim 11 words
The process of claim 13, wherein said nitrogen source is ammonia.
Claim 17
Dependent Claim 12 words
The process of claim 13, wherein said nitrogen source is nitrogen gas.
Claim 18
Dependent Claim 33 words
The process of claim 12, wherein pyrolization of the organometallic precursor compound takes place in the presence of "at least one radical species derived from the group consisting of halogens, ammonia, and hydrogen".

References Cited (Backward Citations)

US4209716A Cited
US5139825A Cited
US5254493A Cited
US5192589A Cited
US5246881A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-03-05 1999-09-04 2000-03-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-03-05 2003-09-04 2004-03-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-03-05 2007-09-04 2008-03-05 $7700.00 Window Closed / Lapsed

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