US5207864A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-temperature fusion of dissimilar semiconductors
Assignee: Rateze Remote Mgmt LLC
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Filing: 1991-12-30
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Granted: 1993-05-04
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Expires: 2011-12-30
Abstract
Abstract A method of fusing together wafers (10, 30) or other semiconductor bodies comprising different semiconductors. In the case that wafers of InP and GaAs or other compound semiconductors are to be bonded, the wafers are cleaned with etchant, and their surfaces are placed together. While the wafers are forced together under moderate pressure and clean hydrogen flows over the wafers, the temperature is raised to 650° C., close to the deposition temperature for epitaxial InP, and maintained for 30 minutes. In the case that one of the wafers is silicon (FIG. 5), both wafers are assembled together in hydrofluoric acid, in which the two wafers bond together by van der Waals force. Then, the assembly is placed in a furnace and annealed at 650° C. A sharp hetero-interface (32, 66, 70) is produced with only surface defects which do not propagate into the bulk. Either wafer may be preformed with a multi-layer opto-electronic structure (12).
Inventors
- 👤 Rajaram Bhat
- 👤 Yu-hwa Lo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:10
CPC Classifications
H; H10; H10P; H10P10/00; H10P10/12; H10P10/128
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
86 words
A fusion method, comprising the steps of: placing a first surface of a first body comprising a first semiconductor in contact with a second surface of a second body comprising a second semiconductor; exposing said bodies to a fluid capable of reducing an oxide of at least one of said semiconductors; and annealing said bodies placed in contact at a temperature not substantially higher than the lowest of respective temperatures of atomic rearrangement of said first and second semiconductors on said first and second surfaces respectively.
Claim 2
Dependent Claim
86 words
A fusion method, comprising the steps of: placing a first surface of a first body comprising a first semiconductor in contact with a second surface of a second body comprising a second semiconductor; exposing said bodies to a fluid capable of reducing an oxide of at least one of said semiconductors; and annealing said bodies placed in contact at a temperature not substantially higher than the lowest of respective temperatures of atomic rearrangement of said first and second semiconductors on said first and second surfaces respectively.
Claim 3
Dependent Claim
15 words
A fusion method as recited in claim 1, wherein both said semiconductors comprise compound semiconductors.
Claim 4
Dependent Claim
40 words
A fusion method as recited in claim 2, further comprising pressing said bodies together with a pressure considerably less than 10 kg/cm 2 during said annealing step and while said bodies are being exposed to said fluid comprising a gas.
Claim 5
Dependent Claim
22 words
A fusion method as recited in claim 1, wherein one of said semiconductors comprises silicon and said fluid comprises a liquid acid.
Claim 6
Dependent Claim
14 words
A fusion method as recited in claim 4, wherein said liquid acid comprises HF.
Claim 7
Dependent Claim
36 words
A fusion method as recited in claim 1, wherein said annealing step produces a higher temperature in the one of said bodies having said lowest temperature of atomic rearrangement than in the other of said bodies.
Claim 8
Dependent Claim
63 words
A fusion method, comprising the steps of: placing a first surface of a first body and comprising a first compound semiconductor in contact with a second surface of a second body and comprising a second compound semiconductor; pressing said two bodies together with a pressure substantially less than 10 kg/cm 2 ; and heating said two bodies pressed together to a fusing temperature.
Claim 9
Dependent Claim
63 words
A fusion method, comprising the steps of: placing a first surface of a first body and comprising a first compound semiconductor in contact with a second surface of a second body and comprising a second compound semiconductor; pressing said two bodies together with a pressure substantially less than 10 kg/cm 2 ; and heating said two bodies pressed together to a fusing temperature.
Claim 10
Dependent Claim
26 words
A fusion method as recited in claim 7, wherein said fusing temperature approximately equals the lowest of respective optimal epitaxial deposition temperatures of said two surfaces.
Claim 11
Dependent Claim
43 words
A fusion method as recited in claim 7, wherein a first one of said bodies has a higher vapor pressure than a second one of said bodies and said heating step heats said first body to a higher temperature than said second body.
Claim 12
Dependent Claim
30 words
A fusion method as recited in claim 7, wherein said first compound semiconductor includes indium as a major constituent and said second compound semiconductor includes gallium as a major constituent.
Claim 13
Dependent Claim
18 words
A fusion method as recited in claim 7, further comprising etching said surfaces prior to said placing step.
Claim 14
Dependent Claim
19 words
A fusion method as recited in claim 11, further comprising flowing hydrogen over said bodies during said heating step.
Claim 15
Dependent Claim
40 words
A fusion method as recited in claim 7, wherein said first surface comprises indium and phosphorus and said second surface comprises gallium and arsenic and said fusing temperature is in a range extending approximately from 550° C. to 650° C.
Claim 16
Dependent Claim
28 words
A fusion method as recited in claim 13, further comprising: etching said surfaces prior to said placing step; and flowing hydrogen over said bodies during said heating step.
Claim 17
Dependent Claim
29 words
A fusion method as recited in claim 13, wherein said first body comprises a plurality of layers beneath said first surface and said second body comprises a GaAs substrate.
Claim 18
Dependent Claim
63 words
A fusion method, comprising: bathing a first surface of a first body comprising a compound semiconductor and a second surface of a second body comprising silicon in an acid capable of dissolving silicon dioxide; contacting said first and second surfaces while they are being bathed by said acid; and annealing said first and second bodies while said first and second surfaces are contacted.
Claim 19
Dependent Claim
63 words
A fusion method, comprising: bathing a first surface of a first body comprising a compound semiconductor and a second surface of a second body comprising silicon in an acid capable of dissolving silicon dioxide; contacting said first and second surfaces while they are being bathed by said acid; and annealing said first and second bodies while said first and second surfaces are contacted.
Claim 20
Dependent Claim
13 words
A fusion method as recited in claim 16, wherein said acid comprises HF.
Claim 21
Dependent Claim
21 words
A fusion method as recited in claim 17, further comprising pressing said first and second bodies together during said annealing step.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-05-03 | 1996-11-02 | 1997-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-03 | 2000-11-02 | 2001-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-03 | 2004-11-02 | 2005-05-04 | $7700.00 | Window Closed / Lapsed |