US3941624A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sn-Doped group III(a)-v(a) Ga-containing layers grown by molecular beam epitaxy
Assignee: AT&T Inc
•
Filing: 1975-03-28
•
Granted: 1976-03-02
•
Expires: 1995-03-28
Abstract
Abstract In order to insure that the doping profiles of Sn-doped Group III(a)-V(a) Ga-containing layers grown by molecular beam epitaxy follow relatively closely the time-intensity profile of the dopant beam, the substrate temperature should not exceed about 550°C.
Inventors
- 👤 Alfred Yi Cho
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:30
CPC Classifications
C; C30; C30B; C30B23/00; C30B23/02; C30B29/00; C30B29/10; C30B29/40; H; H10; H10P; H10P14/00; H10P14/20; H10P14/22; H10P14/29; H10P14/2901; H10P14/2907; H10P14/2911; H10P14/32; H10P14/3202; H10P14/3214; H10P14/3221; H10P14/34; H10P14/3402; H10P14/3414; H10P14/3421; H10P14/3438; H10P14/3441; H10P14/3442; Y; Y10; Y10S; Y10S148/00; Y10S148/018; Y10S148/02; Y10S148/056; Y10S148/065; Y10S148/169
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
170 words
A molecular beam epitaxy technique for fabricating layers of Ga-containing Group III(a)-V(a) compounds with abrupt doping profiles which follow relatively closely the time-intensity profile of a dopant beam, comprising the steps of: a. placing a substrate in an evacuable chamber; b. reducing the background pressure in the chamber to a subatmospheric pressure; c. preheating said substrate to a temperature in the range of about 450° to 650°C, d. directing at least one molecular beam containing Ga and the other constituents of said compound at said substrate for a time period effective to grow said layer to a desired thickness; e. during step (d) directing another molecular beam containing a dopant at said substrate to produce a predetermined doping profile in said layer; CHARACTERIZED IN THAT: 1. said dopant is Sn; 2. said substrate temperature is maintained in the range of about 450° and 550°C so that surface segregation effects of Sn atoms/molecules are alleviated and said doping profile substantially follows the time-intensity profile of said another beam of step (e).
Claim 2
Dependent Claim
170 words
A molecular beam epitaxy technique for fabricating layers of Ga-containing Group III(a)-V(a) compounds with abrupt doping profiles which follow relatively closely the time-intensity profile of a dopant beam, comprising the steps of: a. placing a substrate in an evacuable chamber; b. reducing the background pressure in the chamber to a subatmospheric pressure; c. preheating said substrate to a temperature in the range of about 450° to 650°C, d. directing at least one molecular beam containing Ga and the other constituents of said compound at said substrate for a time period effective to grow said layer to a desired thickness; e. during step (d) directing another molecular beam containing a dopant at said substrate to produce a predetermined doping profile in said layer; CHARACTERIZED IN THAT: 1. said dopant is Sn; 2. said substrate temperature is maintained in the range of about 450° and 550°C so that surface segregation effects of Sn atoms/molecules are alleviated and said doping profile substantially follows the time-intensity profile of said another beam of step (e).
Claim 3
Dependent Claim
21 words
The technique of claim 1 wherein said another molecular beam has a time-intensity profile in the shape of a rectangular pulse.
Claim 4
Dependent Claim
16 words
The technique of claim 2 wherein said other constituents of said one molecular beam include As.
Claim 5
Dependent Claim
10 words
The technique of claim 3 wherein said substrate comprises GaAs.
Claim 6
Dependent Claim
21 words
The technique of claim 4 wherein said substrate is heated to a temperature in the range of about 500° to 550°C.
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) | 1979-03-02 | 1979-09-01 | 1980-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-02 | 1983-09-01 | 1984-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-02 | 1987-09-01 | 1988-03-02 | $7700.00 | Window Closed / Lapsed |