US4319954A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming polycrystalline silicon lines and vias on a silicon substrate
Assignee: RCA Corp
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Filing: 1981-02-27
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Granted: 1982-03-16
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Expires: 2001-02-27
Abstract
Abstract The method involves the formation of conductive, polycrystalline silicon lines and vias by the conversion of amorphous silicon in contact with the underlying silicon substrate through the use of a laser annealing process.
Inventors
- 👤 Lawrence K. White
- 👤 Chung P. Wu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:42
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/056; H10W20/057; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0113; H10P; H10P34/00; H10P34/40; H10P34/42; H10P50/00; H10P50/60; H10P50/66; H10P50/663; H10P50/667; H10W20/067; H10W20/068; Y; Y10; Y10S; Y10S148/00; Y10S148/093
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
84 words
A method of forming polycrystalline silicon lines and vias on a silicon substrate comprising: (a) forming an insulating layer on a surface of said substrate; (b) removing areas of said insulating layer where said lines and vias are to be formed; (c) depositing an amorphous silicon layer over the surface of said substrate; (d) laser annealing said amorphous silicon layer, whereby said portions in contact with said silicon will be selectively converted into polycrystalline silicon; and (e) selectively removing the remaining amorphous silicon areas.
Claim 2
Independent Claim
84 words
A method of forming polycrystalline silicon lines and vias on a silicon substrate comprising: (a) forming an insulating layer on a surface of said substrate; (b) removing areas of said insulating layer where said lines and vias are to be formed; (c) depositing an amorphous silicon layer over the surface of said substrate; (d) laser annealing said amorphous silicon layer, whereby said portions in contact with said silicon will be selectively converted into polycrystalline silicon; and (e) selectively removing the remaining amorphous silicon areas.
Claim 3
Dependent Claim
19 words
The method of claim 1 wherein said insulating layer is formed by the thermal oxidation of said silicon substrate.
Claim 4
Dependent Claim
24 words
The method of claim 1 wherein said insulating layer is formed by the deposition of silicon dioxide on the surface of said silicon substrate.
Claim 5
Dependent Claim
30 words
The method of claim 2 or claim 3 wherein said step of removing areas of said insulating layer is accomplished by etching following a photolithographic exposure of a photoresist layer.
Claim 6
Dependent Claim
20 words
The method of claim 4 wherein said amorphous silicon layer is deposited in a low pressure chemical vapor deposition process.
Claim 7
Dependent Claim
18 words
The method of claim 5 wherein said laser annealing step is accomplished using a pulsed frequency-doubled Nd:YAG laser.
Claim 8
Dependent Claim
16 words
The method of claim 6 wherein said laser is operated at a wavelength of 0.53 μm.
Claim 9
Dependent Claim
21 words
The method of claim 7 wherein the dose of said laser is between 0.1 Joules/cm 2 and 0.8 Joules/cm 2 .
Claim 10
Dependent Claim
18 words
The method of claim 8 wherein said selective removal of remaining amorphous silicon areas is accomplished by etching.
Claim 11
Dependent Claim
25 words
The method of claim 9 wherein said etching for selective removal of amorphous silicon is conducted in a solution of nitric, hydrofluoric, and acetic acids.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-03-15 | 1985-09-14 | 1986-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-03-15 | 1989-09-14 | 1990-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-03-15 | 1993-09-14 | 1994-03-16 | $7700.00 | Window Closed / Lapsed |