Claims
- 1. A luminescent diode comprising:
- A p+ type substrate;
- at least one unit consisting of a p-type layer of a certain band gap and an n-type layer of a band gap wider than said certain band gap and epitaxially grown on said p-type layer to form a heterojunction at the interface between said p-type layer and said n-type layer, said unit being disposed in such a way that said p-type layer is located closer to said substrate than is said n-type layer, the band gap of said p-type layer increasing gradually with distance from said substrate;
- said substrate being capable of absorbing light entering there into from said p-type layer; and
- a low resistivity contact disposed on an outermost surface of said unit opposite to said substrate, said contact having an area contacting said outermost surface smaller than the area of said outermost surface for allowing a light output to be taken at said outermost surface.
- 2. A luminescent diode comprising:
- A p+ type substrate;
- at least one unit consisting of a p-type layer of a certain band gap and an n-type layer of a band gap wider than said certain band gap and epitaxially grown on said p-type layer to form a heterojunction at the interface between said p-type layer and said n-type layer, said unit being disposed in such a way that said p-type layer is located closer to said substrate than is said n-type layer, the and gap of said p-type layer increasing monotonically with distance from said substrate;
- said substrate being capable of absorbing light entering there into from said p-type layer; and
- a low resistivity contact disposed on an outermost surface of said unit opposite to said substrate, said contact having an area contacting said outermost surface smaller than the area of said outermost surface for allowing a light output to be taken at said outermost surface.
- 3. A luminous diode comprising:
- a P+ type substrate having a first constant band gap;
- a P type layer disposed on said substrate having a second constant band gap wider than said first band gap;
- an N type layer disposed on the P type layer having a third band gap wider than said second band gap; and
- a low resistivity contact disposed on an outermost surface of said diode opposite to said substrate, said contact having an area contacting said outermost surface smaller than the area of said outermost surface for allowing a light output to be taken at said outermost surface.
- 4. A luminescent diode comprising:
- a p+ type substrate;
- at least one unit consisting of a p- type layer of a certain band gap and a n-type layer of a band gap wider than said certain band gap and epitaxially grown on said p-type layer to form a hetrojunction at the interface between said p-type layer and said n-type layer, said unit being disposed in such a way that said p-type layer is located closer to said substrate than is said n- type later, the band gap of said unit increasing monotonically with distance from said substrate;
- said substrate being capable of absorbing light entering there into from said p- type layer; and
- a low resistivity contact disposed on an outermost surface of said unit opposite to said substrate, said contact having an area contacting said outermost surface smaller than the area of said outermost surface for allowing a light output to be taken at said outermost surface.
- 5. A luminous diode comprising:
- a semiconductor body having first and second opposing principle surfaces include a P+ type substrate adjacent to said first principle surface, a P type layer formed on said substrate and an N type layer formed on said P type layer adjacent to said second principle surface and forming a hetrojunction with said P type layer, the band gap in said semiconductor body increasing monotonically from said first principle to said second principle surface, and
- a low resistivity contact disposed on said second principle surface, said contact having an area contacting said second principle surface smaller than the area of said principle surface thereby allowing a light output to be taken at said second principle surface.
- 6. A luminescent diode according to claim 1, 2 or 4, wherein: said unit is epitaxially grown on said substrate.
- 7. A luminescent diode according to claim 1, 2 or 4, wherein: said contact is of an n.sup.+ type semiconductor and epitaxially grown on said outermost surface of said unit.
- 8. A luminescent diode according to claim 1, 2, 3, 4 or 5, wherein: said substrate is made of GaAs, said p-type layer is made of Ga.sub.1-x Al.sub.x As and said n-type layer is made of Ga.sub.1-y Al.sub.y As, wherein y>x.
- 9. A luminescent diode according to claim 8, wherein: x is a positive number less than 0.35 and 0.35<y.ltoreq.0.65.
- 10. A luminescent diode according to claim 3, wherein said contact is of a mesh structure.
- 11. A luminescent diode according to claims 3 or 5 wherein said P type layer is epitaxially grown on said substrate.
- 12. A luminescent diode according to claim 5 wherein said contact is of an N+ type semiconductor and epitaxially grown on said second principle surface.
- 13. A luminscent diode according to claim 9 wherein 0.2<x.ltoreq.0.35.
- 14. The luminescent diode of claim 11 wherein said contact is of a mesh structure.
Priority Claims (1)
Number |
Date |
Country |
Kind |
46-100623 |
Dec 1971 |
JPX |
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CROSS REFERENCE TO RELATED APPLICATION
This is a continuation of my copending application Ser. No. 867,158 filed Jan. 5, 1978, abandoned upon the filing hereof, which was a Continuation-In-Part of my application Ser. No. 761,468 filed on Jan. 21, 1977, now abandoned which was a Rule 60 Continuation of my great grandparent application Ser. No. 543,617 filed on Jan. 24, 1975 (now abandoned) which was a Continuation-In-Part of my great great-grandparent application Ser. No. 314,393 filed on Dec. 12, 1972 (now abandoned).
US Referenced Citations (5)
Continuations (2)
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Number |
Date |
Country |
Parent |
867158 |
Jan 1978 |
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Parent |
543617 |
Jan 1975 |
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Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
761468 |
Jan 1977 |
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Parent |
314393 |
Dec 1972 |
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