US5094977A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stress reduction in metal films by laser annealing
Assignee: Micron Technology Inc
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Filing: 1991-01-25
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Granted: 1992-03-10
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Expires: 2011-01-25
Abstract
Abstract A method of processing a semiconductor wafer comprises, a) chemical vapor depositing (CVD) a metal layer atop a semiconductor substrate; and b) impinging laser energy upon the CVD metal layer at an optical fluence of from 0.05 Joules/cm 2 to 0.30 Joules/cm 2 for a period of time sufficient to relieve mechanical stress associated with the CVD metal layer yet insufficient to melt the CVD metal layer. In accordance with another aspect of the invention, such treatment method could also be used to form a desired silicide layer in the same step.
Inventors
- 👤 Chang Yu
- 👤 Trung T. Doan
- 👤 Gurtej S. Sandhu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:08
CPC Classifications
H; H10; H10P; H10P95/00; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0112; Y; Y10; Y10S; Y10S148/00; Y10S148/09; Y10S148/093
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
68 words
A method of processing a semiconductor wafer comprising the following steps: chemical vapor depositing (CVD) a metal layer atop a semiconductor substrate; and impinging laser energy upon the CVD metal layer at an optical fluence of from 0.05 Joules/cm 2 to 0.30 Joules/cm 2 for a period of time sufficient to relieve mechanical stress associated with the CVD metal layer yet insufficient to melt the CVD metal layer.
Claim 2
Independent Claim
68 words
A method of processing a semiconductor wafer comprising the following steps: chemical vapor depositing (CVD) a metal layer atop a semiconductor substrate; and impinging laser energy upon the CVD metal layer at an optical fluence of from 0.05 Joules/cm 2 to 0.30 Joules/cm 2 for a period of time sufficient to relieve mechanical stress associated with the CVD metal layer yet insufficient to melt the CVD metal layer.
Claim 3
Dependent Claim
40 words
The method of processing a semiconductor wafer of claim 1 further comprising preheating the semiconductor substrate to an elevated temperature prior to impinging laser energy upon the CVD metal layer, and maintaining the substrate at the elevated temperature during treatment.
Claim 4
Dependent Claim
21 words
The method of processing a semiconductor wafer of claim 2 wherein the elevated temperature is from 200° C. to 500° C.
Claim 5
Dependent Claim
21 words
The method of processing a semiconductor wafer of claim 2 wherein the elevated temperature is from 300° C. to 400° C.
Claim 6
Dependent Claim
28 words
The method of processing a semiconductor wafer of claim 1 wherein the metal of the metal layer is selected from the group consisting of tungsten and titanium nitride.
Claim 7
Dependent Claim
59 words
The method of processing a semiconductor wafer of claim 1 wherein the metal of the metal layer is selected from the group consisting of tungsten and titanium nitride, and further comprising: preheating the semiconductor substrate to an elevated temperature prior to impinging laser energy upon the CVD metal layer, and maintaining the substrate at the elevated temperature during treatment.
Claim 8
Dependent Claim
21 words
The method of processing a semiconductor wafer of claim 6 wherein the elevated temperature is from 200° C. to 500° C.
Claim 9
Dependent Claim
21 words
The method of processing a semiconductor wafer of claim 6 wherein the elevated temperature is from 300° C. to 400° C.
Claim 10
Independent Claim
126 words
A method of processing a semiconductor wafer comprising the following steps: depositing a first layer of first metal atop a semiconductor substrate for subsequent formation of a silicide with silicon of the substrate; chemical vapor depositing (CVD) a another metal layer atop the first metal layer for formation of electrically conductive interconnecting lines; and impinging laser energy upon the CVD metal layer at an optical fluence of from 0.05 Joules/cm 2 to 0.30 Joules/cm 2 for a period of time sufficient to both, a) relieve mechanical stress associated with the CVD metal layer, and b) form a silicide layer by reaction of the first metal layer with underlying silicon of the substrate, the period of time being insufficient to melt the first and CVD metal layers.
Claim 11
Independent Claim
126 words
A method of processing a semiconductor wafer comprising the following steps: depositing a first layer of first metal atop a semiconductor substrate for subsequent formation of a silicide with silicon of the substrate; chemical vapor depositing (CVD) a another metal layer atop the first metal layer for formation of electrically conductive interconnecting lines; and impinging laser energy upon the CVD metal layer at an optical fluence of from 0.05 Joules/cm 2 to 0.30 Joules/cm 2 for a period of time sufficient to both, a) relieve mechanical stress associated with the CVD metal layer, and b) form a silicide layer by reaction of the first metal layer with underlying silicon of the substrate, the period of time being insufficient to melt the first and CVD metal layers.
Claim 12
Dependent Claim
30 words
The method of processing a semiconductor wafer of claim 9 further comprising preheating the semiconductor substrate to an elevated temperature prior to impinging laser energy upon the CVD metal layer.
Claim 13
Dependent Claim
21 words
The method of processing a semiconductor wafer of claim 10 wherein the elevated temperature is from 200° C. to 500° C.
Claim 14
Dependent Claim
21 words
The method of processing a semiconductor wafer of claim 10 wherein the elevated temperature is from 300° C. to 400° C.
Claim 15
Dependent Claim
25 words
The method of processing a semiconductor wafer of claim 9 wherein the CVD metal is selected from the group consisting of tungsten and titanium nitride.
Claim 16
Independent Claim
167 words
A method of processing a semiconductor wafer comprising the following sequential steps: depositing a first layer of first metal atop a semiconductor substrate for subsequent formation of a silicide with silicon of the substrate; depositing a second layer of second metal atop the first metal layer for formation of a barrier metal layer; heating the substrate to a temperature of from 200° C. to 500° C.; chemical vapor depositing (CVD) tungsten or titanium nitride atop the second metal layer for formation of electrically conductive interconnecting lines; and impinging laser energy upon the tungsten or titanium nitride CVD metal layer at an optical fluence of from 0.05 Joules/cm 2 to 0.30 Joules/cm 2 for a period of time sufficient to both, a) relieve mechanical stress associated with the tungsten or titanium nitride CVD metal layer, and b) form a silicide layer by reaction of the first metal layer with underlying silicon of the substrate, the period of time being insufficient melt the first, second and CVD metal layers.
Claim 17
Independent Claim
167 words
A method of processing a semiconductor wafer comprising the following sequential steps: depositing a first layer of first metal atop a semiconductor substrate for subsequent formation of a silicide with silicon of the substrate; depositing a second layer of second metal atop the first metal layer for formation of a barrier metal layer; heating the substrate to a temperature of from 200° C. to 500° C.; chemical vapor depositing (CVD) tungsten or titanium nitride atop the second metal layer for formation of electrically conductive interconnecting lines; and impinging laser energy upon the tungsten or titanium nitride CVD metal layer at an optical fluence of from 0.05 Joules/cm 2 to 0.30 Joules/cm 2 for a period of time sufficient to both, a) relieve mechanical stress associated with the tungsten or titanium nitride CVD metal layer, and b) form a silicide layer by reaction of the first metal layer with underlying silicon of the substrate, the period of time being insufficient melt the first, second and CVD metal layers.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1995-03-10 | 1995-09-09 | 1996-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-10 | 1999-09-09 | 2000-03-10 | $3760.00 | Window Closed / Lapsed |
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