US4075654A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor photoelectron emission device
Assignee: Hamamatsu Terebi KK
•
Filing: 1976-10-26
•
Granted: 1978-02-21
•
Expires: 1996-10-26
Abstract
Abstract Semiconductor photoelectron emission device comprising mixed crystals of two or more different semiconductors forming a heterojunction with direct transition type defining a first region in which may be excited by photoelectrons and an indirect transition type defining a second region whose forbidden band gap is wider than that of the first region and the surface of which is a photoelectron emission surface.
Inventors
- 👤 Katsuo Hara
- 👤 Minoru Hagino
- 👤 Tokuzo Sukegawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:57
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/12; H01J1/00; H01J1/02; H01J1/34; H01J29/00; H01J29/02; H01J29/10; H01J29/36; H01J29/39; H01J29/45; H01J29/451; H01J2201/00; H01J2201/34; H01J2201/342; H01J2201/3421; H01J2201/3423
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
141 words
A semiconductor photoelectron emission device comprising an electrode; a base of direct transition semiconductor of p-type GaSb having an impurity concentration of about 10 17 to 10 19 atom/cm 3 ; a first layer of n-type GaSb having a thickness of about 10μm epitaxially grown on and covering selected parts of said base; a second layer of indirect transition semiconductor of Al.sub.(1-x) Ga x Sb, wherein x is less than 1 and a positive number, having a wide forbidden band and low impurity concentration and of 500 A to 10μm thickness and defining a heterojunction with said base, said base and said second layer having substantially the same crystal structure at said junction and having small differences in lattice constants; a third layer of Al.sub.(1-x) Ga.sub.(1-x) Sb having a narrower forbidden band and with an electron emissive surface; and ohmic contacts.
Claim 2
Dependent Claim
141 words
A semiconductor photoelectron emission device comprising an electrode; a base of direct transition semiconductor of p-type GaSb having an impurity concentration of about 10 17 to 10 19 atom/cm 3 ; a first layer of n-type GaSb having a thickness of about 10μm epitaxially grown on and covering selected parts of said base; a second layer of indirect transition semiconductor of Al.sub.(1-x) Ga x Sb, wherein x is less than 1 and a positive number, having a wide forbidden band and low impurity concentration and of 500 A to 10μm thickness and defining a heterojunction with said base, said base and said second layer having substantially the same crystal structure at said junction and having small differences in lattice constants; a third layer of Al.sub.(1-x) Ga.sub.(1-x) Sb having a narrower forbidden band and with an electron emissive surface; and ohmic contacts.
Claim 3
Dependent Claim
14 words
The device of claim 1, wherein further comprising means for providing drift electric fields.
Claim 4
Dependent Claim
25 words
The device of claim 1, wherein lattice sites of the mixed crystals have atoms thereof replaced with other atoms of In, Bi, As and P.
Claim 5
Dependent Claim
18 words
The device of claim 1, wherein said GaSb has an effective forbidden band of 0.7 to 1.25 eV.
Claim 6
Dependent Claim
20 words
The device of claim 1, wherein said third layer has a thickness equivalent of less than the electron diffusion length.
References Cited (Backward Citations)
US3696262A
Cited
US3814996A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-20 | 1981-08-22 | 1982-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-20 | 1985-08-22 | 1986-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-20 | 1989-08-22 | 1990-02-21 | $7700.00 | Window Closed / Lapsed |