US3993533A
Expired / Lapsed
US
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Method for making semiconductors for solar cells
Assignee: Carnegie Mellon University
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Filing: 1975-04-09
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Granted: 1976-11-23
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Expires: 1995-04-09
Abstract
Abstract The invention relates to a method for producing a desired thin semiconductor film for use in solar cells. The desired semiconductor is grown epitaxially on a second semiconductor film which may be epitaxial on a third semiconductor. The second semiconductor has a lower melting point than the desired semiconductor. The temperature of the second semiconductor is increased. This creates a molten state in the second semiconductor and the desired semiconductor is stripped away from the second semiconductor. The desired film may be detached by dissolving the second semiconductor with a chemical agent that dissolves the second semiconductor.
Inventors
- 👤 Arthur G. Milnes
- 👤 Donald L. Feucht
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:48
CPC Classifications
B; B32; B32B; B32B43/00; C; C30; C30B; C30B25/00; C30B25/02; C30B25/18; H; H10; H10F; H10F71/00; H10F71/121; H10F71/1212; H10F71/1215; H10F71/125; H10F71/127; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/543; Y02E10/544; Y02E10/547; Y02P; Y02P70/00; Y02P70/50; Y10; Y10S; Y10S117/00; Y10S117/915; Y10S148/00; Y10S148/051; Y10S148/063; Y10S148/067; Y10S148/072; Y10S148/12; Y10S148/135; Y10S148/15
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
76 words
A method for producing a desired thin semiconductor film for use in solar cells comprising: a. growing epitaxially the desired semiconductor film on a second semiconductor film which has been epitaxially grown on a third semiconductor, the second semiconductor film having a lower melting point than the desired semiconductor film and the third semiconductor; b. increasing the temperature of the second semiconductor film to create a molten state; and then c. detaching the desired semiconductor film.
Claim 2
Independent Claim
76 words
A method for producing a desired thin semiconductor film for use in solar cells comprising: a. growing epitaxially the desired semiconductor film on a second semiconductor film which has been epitaxially grown on a third semiconductor, the second semiconductor film having a lower melting point than the desired semiconductor film and the third semiconductor; b. increasing the temperature of the second semiconductor film to create a molten state; and then c. detaching the desired semiconductor film.
Claim 3
Dependent Claim
25 words
A method as recited in claim 1 wherein the desired semiconductor film, the second semiconductor film and the third semiconductor have a substantial lattice match.
Claim 4
Dependent Claim
17 words
A method as recited in claim 2 wherein the desired semiconductor film is substantially a single crystal.
Claim 5
Dependent Claim
16 words
A method as recited in claim 3 wherein the desired semiconductor is a film of silicon.
Claim 6
Dependent Claim
22 words
A method as recited in claim 3 wherein the second semiconductor is selected from the group consisting of Ge and Ge-Si alloy.
Claim 7
Dependent Claim
14 words
A method as recited in claim 3 wherein the second semiconductor is Ge-Si alloy.
Claim 8
Dependent Claim
18 words
A method as recited in claim 3 wherein the desired semiconductor film contains at least one pn junction.
Claim 9
Dependent Claim
16 words
A method as recited in claim 3 in which the third semiconductor is a single crystal.
Claim 10
Dependent Claim
24 words
A method as recited in claim 3 wherein the third semiconductor is a single crystal selected from the group consisting of Si and GaAs.
Claim 11
Dependent Claim
24 words
A method as recited in claim 3 wherein the third semiconductor is a single crystal selected from the group consisting of InAs and InP.
Claim 12
Dependent Claim
24 words
A method as recited in claim 3 wherein the third semiconductor is a single crystal selected from the group consisting of CdTe and CdSe.
Claim 13
Dependent Claim
18 words
A method as recited in claim 3 wherein the desired semiconductor film contains a plurality of different semiconductors.
Claim 14
Dependent Claim
35 words
A method as recited in claim 3 wherein the second semiconductor is selected from the group consisting of Ge and Ge-Si alloy and the third semiconductor being selected from the group of Si and GaAs.
Claim 15
Dependent Claim
37 words
A method as recited in claim 3 wherein the desired semiconductor film is a crystal selected from the group consisting of GaAs, GaAs x P 1 -x , Al y Ga 1 -y As, AlSb and InP.
Claim 16
Dependent Claim
24 words
A method as recited in claim 3 wherein the desired semiconductor film is a crystal selected from the group consisting of CdTe and CdSe.
Claim 17
Dependent Claim
18 words
A method as recited in claim 3 wherein the desired semiconductor film is detached by a vacuum means.
Claim 18
Dependent Claim
44 words
A method as recited in claim 3 wherein the desired semiconductor film is detached by soldering metal contacts to the desired semiconductor, the solder having a melting point between the melting point of the second semiconductor, and the other two semiconductors (first and third).
Claim 19
Dependent Claim
41 words
A method as recited in claim 3 wherein the desired semiconductor film is detached by a slab that rides off the second semiconductor and carries the desired semiconductor film with it thereby detaching the desired semiconductor film from the second semiconductor.
Claim 20
Dependent Claim
36 words
A method as recited in claim 3 wherein the desired single crystal thin semiconductor film is formed of binary, ternary and quaternary semiconductors from columns II, III, IV, V and VI of the atomic periodic chart.
Claim 21
Independent Claim
78 words
A method for producing a desired thin semiconductor film for use in solar cells comprising: a. growing epitaxially the desired semiconductor film on a second semiconductor film which has been epitaxially grown on a third semiconductor film, the second semiconductor having greater solubility in a chemical agent than the desired semiconductor film and the third semiconductor; b. immersing the films in a chemical agent to dissolve the second semiconductor film; and then c. detaching the desired semiconductor film.
Claim 22
Independent Claim
78 words
A method for producing a desired thin semiconductor film for use in solar cells comprising: a. growing epitaxially the desired semiconductor film on a second semiconductor film which has been epitaxially grown on a third semiconductor film, the second semiconductor having greater solubility in a chemical agent than the desired semiconductor film and the third semiconductor; b. immersing the films in a chemical agent to dissolve the second semiconductor film; and then c. detaching the desired semiconductor film.
Claim 23
Dependent Claim
22 words
A method as recited in claim 20 wherein the desired semiconductor film is selected from the group consisting of GaAs and InP.
Claim 24
Dependent Claim
26 words
A method as recited in claim 20 wherein the second semiconductor is selected from the group consisting of CdS and Al x Ga 1 -x As.
Claim 25
Dependent Claim
24 words
A method as recited in claim 20 wherein the third semiconductor is a single crystal selected from the group consisting of InP and GaAs.
Claim 26
Dependent Claim
36 words
A method as recited in claim 20 wherein the desired single crystal thin semiconductor film is formed of binary, ternary and quaternary semiconductors from columns II, III, IV, V and VI of the atomic periodic chart.
Claim 27
Dependent Claim
44 words
A method as recited in claim 20 wherein the desired semiconductor film is detached by a slab that rides off the second semiconductor during chemical dissolution and carries the desired semiconductor film with it thereby detaching the desired semiconductor film from the second semiconductor.
Claim 28
Dependent Claim
25 words
A method as recited in claim 20 wherein the desired semiconductor film is detached by a vacuum means during chemical dissolution of the second semiconductor.
References Cited (Backward Citations)
US3366516A
Cited
US3645823A
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US3621565A
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US3655496A
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US3847686A
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US3846198A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-11-23 | 1980-05-24 | 1980-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-11-23 | 1984-05-24 | 1984-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-11-23 | 1988-05-24 | 1988-11-23 | $7700.00 | Window Closed / Lapsed |