US5783282A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Resputtering to achieve better step coverage of contact holes
Assignee: Round Rock Research LLC
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Filing: 1996-10-07
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Granted: 1998-07-21
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Expires: 2016-10-07
Abstract
Abstract An improved apparatus and method for manufacturing semiconductor devices, and, in particular, for depositing material at the bottom of a contact hole, comprises sputtering a material onto a semiconductor substrate; applying a first bias voltage to the substrate, simultaneously removing the material surrounding the contact hole to form a facet at the top of the recess; and applying a second bias voltage to the substrate, simultaneously sputter-depositing the first material onto the bottom of the recess. A further embodiment of the invention utilizes an electrically isolated collimator for the sputtering apparatus. Another embodiment of the invention resputters a first material onto sidewalls of a contact hole during physical vapor deposition.
Inventors
- 👤 Shane P. Leiphart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:14
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/34; C23C14/3435; C23C14/345; C23C14/04; C23C14/046; C23C14/58; C23C14/5806; H; H01; H01J; H01J37/00; H01J37/32; H01J37/34; H01J37/3411; H01J37/3447; H01J37/345; H01J37/3455; H10; H10P; H10P14/00; H10P14/40; H10P14/42; H10P14/44; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033; H10W20/047; H10W20/048; H10W20/052; H10W20/0523; H10W20/054; H10W20/056; H10W20/071; H10W20/081; H10W20/082; H01J2237/00; H01J2237/32; H01J2237/33; H01J2237/332; H01J2237/3322; H01J2237/3327; Y; Y10; Y10S; Y10S438/00; Y10S438/978; Y10T; Y10T428/00; Y10T428/24; Y10T428/24273; Y10T428/24322; Y10T428/24331
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
57 words
A contact hole, defined by a bottom and sidewalls, comprising titanium silicide on the bottom and a substantially continuous layer of titanium nitride on the sidewalls, wherein the titanium nitride is formed by: physical vapor deposition of titanium into the contact hole; resputtering the titanium onto the sidewalls; and annealing the contact hole in a nitrogen-containing ambient.
Claim 2
Dependent Claim
57 words
A contact hole, defined by a bottom and sidewalls, comprising titanium silicide on the bottom and a substantially continuous layer of titanium nitride on the sidewalls, wherein the titanium nitride is formed by: physical vapor deposition of titanium into the contact hole; resputtering the titanium onto the sidewalls; and annealing the contact hole in a nitrogen-containing ambient.
Claim 3
Independent Claim
108 words
A method of depositing a first material onto a semiconductor substrate which comprises a recess, having a bottom, and defined by sidewalls comprising a second material, the method comprising the steps of: sputtering the first material onto the semiconductor substrate, to form a layer of sputterdeposited material; applying a first bias voltage to the substrate sufficient to create a facet on the sputter-deposited material, but not sufficient enough to create a facet on the second material, while simultaneously resputtering the sputter-deposited material; and applying a second bias voltage to the substrate following formation of the facet while simultaneously sputter-depositing the first material onto the bottom of the recess.
Claim 4
Independent Claim
108 words
A method of depositing a first material onto a semiconductor substrate which comprises a recess, having a bottom, and defined by sidewalls comprising a second material, the method comprising the steps of: sputtering the first material onto the semiconductor substrate, to form a layer of sputterdeposited material; applying a first bias voltage to the substrate sufficient to create a facet on the sputter-deposited material, but not sufficient enough to create a facet on the second material, while simultaneously resputtering the sputter-deposited material; and applying a second bias voltage to the substrate following formation of the facet while simultaneously sputter-depositing the first material onto the bottom of the recess.
Claim 5
Dependent Claim
43 words
The method of claim 2, in which the first material comprises a refractory metal, selected from the group consisting of titanium, tungsten, tantalum, and molybdenum and the second material comprises an insulating material, selected from the group consisting of oxides and borophosphosilicate glass.
Claim 6
Dependent Claim
14 words
The method of claim 2, in which the recess comprises a contact hole opening.
Claim 7
Dependent Claim
16 words
The method of claim 2, in which the sputtering step comprises utilizing a collimator for sputtering.
Claim 8
Dependent Claim
17 words
The method of claim 5, in which the collimator utilized is electrically isolated from the sputtering system.
Claim 9
Dependent Claim
17 words
The method of claim 2, in which the first bias voltage is approximately 550 to 750 Volts.
Claim 10
Dependent Claim
38 words
The method of claim 2, in which the second bias voltage is sufficient to prevent overhang of the first material from forming on the top of the recess, but not large enough to further facet the sputter-deposited material.
Claim 11
Dependent Claim
17 words
The method of claim 2, in which the second bias voltage is approximately 150 to 250 Volts.
Claim 12
Dependent Claim
29 words
The method of claim 2, in which the second bias voltage is sufficient to resputter a portion of the first material deposited on the recess bottom onto the sidewalls.
Claim 13
Dependent Claim
23 words
The method of claim 2, in which the second bias voltage is approximately at least the sputtering threshold voltage of the first material.
Claim 14
Dependent Claim
33 words
The method of claim 2, in which the facet formed at the top of the recess has an angle corresponding to the angle at which the first material has the highest sputter yield.
Claim 15
Dependent Claim
21 words
The method of claim 2, in which the time period for the first bias voltage is less than approximately 60 seconds.
Claim 16
Independent Claim
90 words
A method of depositing titanium into a recess, defined by a recess bottom and further defined by sidewalls comprising a second material, the method comprising the steps of: sputtering the titanium onto the recess bottom while applying a bias voltage to an underlying substrate, to simultaneously resputter the titanium from the bottom of the recess onto the sidewalls; and annealing to form titanium nitride on the sidewalls and titanium silicide on the recess bottom wherein the sputtering step and the annealing step are performed in the same high vacuum chamber.
Claim 17
Independent Claim
90 words
A method of depositing titanium into a recess, defined by a recess bottom and further defined by sidewalls comprising a second material, the method comprising the steps of: sputtering the titanium onto the recess bottom while applying a bias voltage to an underlying substrate, to simultaneously resputter the titanium from the bottom of the recess onto the sidewalls; and annealing to form titanium nitride on the sidewalls and titanium silicide on the recess bottom wherein the sputtering step and the annealing step are performed in the same high vacuum chamber.
Claim 18
Dependent Claim
14 words
The method of claim 14, in which the recess comprises a contact hole opening.
Claim 19
Dependent Claim
23 words
The method of claim 14, in which the bias voltage is at least as great as the sputtering threshold of the first material.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-07-20 | 2002-01-19 | 2002-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-07-20 | 2006-01-19 | 2006-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-07-20 | 2010-01-19 | 2010-07-21 | $7700.00 | Window Closed / Lapsed |