US5075257A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aerosol deposition and film formation of silicon
Assignee: University of Arkansas System
•
Filing: 1990-11-09
•
Granted: 1991-12-24
•
Expires: 2010-11-09
Abstract
Abstract A novel method for the deposition of silicon and the formation of silicon films. More specifically, the process provides an aerosol generating technique, wherein silicon powder of optimum particle size is aerosolized, charged, and then electrostatically deposited onto high melting point substrates, which may include semiconducting, insulating, and conducting materials such as silicon, sapphire, and molybdenum, respectively. The powder coated substrates are subsequently heat treated at optimum times and temperatures, resulting in the formation of polycrystalline silicon films.
Inventors
- 👤 Roger M. Hawk
- 👤 Kamesh V. Gadepally
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:43
CPC Classifications
B; B05; B05B; B05B5/00; B05B5/025; B05B5/03; B05B5/032; H; H10; H10P; H10P14/00; H10P14/20; H10P14/22; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/2921; H10P14/2923; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/36
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
79 words
A method for the deposition of silicon and the formation of a silicon film on substrates, comprising the steps of: a) aerosolizing and electrostatically charging silicon powder particles with electrostatic charges of one polarity; b) grounding a substrate to provide an opposite polarity on the substrate; c) coating the charged particles of silicon powder on the substrate to form a powder coated substrate; and d) thereafter heat treating the coated substrate to form a silicon film on the substrate.
Claim 2
Independent Claim
79 words
A method for the deposition of silicon and the formation of a silicon film on substrates, comprising the steps of: a) aerosolizing and electrostatically charging silicon powder particles with electrostatic charges of one polarity; b) grounding a substrate to provide an opposite polarity on the substrate; c) coating the charged particles of silicon powder on the substrate to form a powder coated substrate; and d) thereafter heat treating the coated substrate to form a silicon film on the substrate.
Claim 3
Dependent Claim
20 words
The method of claim 1, wherein said substrates are selected from the group consisting of semiconducting, insulating, and conducting materials.
Claim 4
Dependent Claim
11 words
The method of claim 2, wherein said semiconducting material is silicon.
Claim 5
Dependent Claim
10 words
The method of claim 3, wherein said silicon is n-doped.
Claim 6
Dependent Claim
10 words
The method of claim 3, wherein said silicon is p-doped.
Claim 7
Dependent Claim
11 words
The method of claim 2, wherein said insulating material is sapphire.
Claim 8
Dependent Claim
11 words
The method of claim 2, wherein said conducting material is molybdenum.
Claim 9
Dependent Claim
21 words
The method of claim 1, wherein the heat treatment of the coated substrate is conducted in an atmosphere of flowing argon.
Claim 10
Dependent Claim
40 words
The method of claim 1, wherein heat treating thepowder coated substrate in step d) is conducted for approximately 1-24 hours and between the temperatures of approximately 1000° C. and 1430° C. to melt the powder and form a silicon film.
Claim 11
Dependent Claim
12 words
The method of claim 1, wherein the silicon film produced is polycrystalline.
Claim 12
Independent Claim
47 words
The method of claim wherein the thickness of the deposition of the silicon powder in step c) is controlled by the length of time of step c), the velocity of the coating of step c), and the electrostatic charge level differential between the particles and the substrate.
Claim 13
Dependent Claim
16 words
The method of claim 1, wherein the charged particles travel approximately 17 cm to the substrate.
Claim 14
Dependent Claim
25 words
The method of claim 11, wherein the length of the spray time for the deposition of the silicon powder particles ranges between approximately 1-3 seconds.
Claim 15
Dependent Claim
20 words
The method of claim 11, wherein the velocity of the coating of step c) is approximately 11.2 Nm 3 /hr.
Claim 16
Dependent Claim
17 words
The method of claim 11, wherein the electrostatic charge level ranges between 0 and 100,000 volts DC.
Claim 17
Dependent Claim
13 words
The method of claim 15, wherein the electrostatic charge level is 75 kV.
Claim 18
Dependent Claim
17 words
The method of claim 1, wherein the silicon powder is particulate in a -325 mesh size range.
Claim 19
Dependent Claim
22 words
The method of claim 1, wherein the substrate is sapphire and wherein there at treating step d) is 1400° C., 12 hours.
Claim 20
Dependent Claim
22 words
The method of claim 1, wherein the substrate is silicon and wherein the heat treating step d) is 1050° C., 21 hours.
Claim 21
Dependent Claim
22 words
The method of claim 1, wherein he substrate is molybdenum and wherein the heat treating step d) is 1430° C. 12 hours.
Claim 22
Dependent Claim
25 words
The method of claim 1, wherein the substrate is silicon dioxide on silicon and wherein the heat treating sep d) is 1100° C., 6-12 hours.
Claim 23
Dependent Claim
25 words
The method of claim 1, wherein the substrate is silicon nitride on silicon and wherein the heat trating step d) is 1025° C., 12 hours.
References Cited (Backward Citations)
US4233338A
Cited
US4449286A
Cited
US4440800A
Cited
US4357200A
Cited
US4332838A
Cited
US4615903A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-12-23 | 1995-06-24 | 1995-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-23 | 1999-06-24 | 1999-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-23 | 2003-06-24 | 2003-12-24 | $7700.00 | Window Closed / Lapsed |