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US4706101A Expired / Lapsed US ⏱️ 0.0 years remaining

Light emitting diode formed of a compound semiconductor material

Assignee: Toshiba Corp
•
Filing: 1985-08-20
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Granted: 1987-11-10
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Expires: 2005-08-20
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Abstract

Abstract A light emitting diode is disclosed which includes an N-GaAs substrate, a double hetero-junction structure obtained by forming an N-GaAlAs clad layer, a P-GaAs active layer and a P-GaAlAs clad layer on the substrate in that order, and a current narrowing structure obtained by selectively forming a contact metal on the P-GaAlAs clad layer in the double hetero-junction structure with the contact metal formed around the contact metal. In the light emitting diode so manufactured, the double hetero-junction structure is formed by a metal organic vapor deposition method. The N-GaAlAs clad layer is of a three-layer structure with one layer of a narrower forbidden band width sandwiched between the remaining two layers of a wider forbidden band width.

Inventors

  • 👤 Masaru Nakamura
  • 👤 Masaki Okajima
  • 👤 Tadashi Komatsubara
  • 👤 Tetsuo Sadamasa
  • 👤 Koichi Nitta

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 01:17
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/01; H10H20/011; H10H20/013; H10H20/80; H10H20/81; H10H20/811; H10H20/822; H10H20/824

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 161 words
In a light emitting diode made of a compound semiconductor material, comprising: a semiconductor substrate of a first conductivity type; a double hetero-junction structure obtained by sequentially forming at least a clad layer of a first conductivity type, an active layer, and a clad layer of the second conductivity type by a vapor deposition method on the substrate in that order; and a current narrowing structure obtained by selectively forming a contact metal on the clad layer of the second conductivity type in the double hetero-junction structure with an insulating film formed around the contact metal, in which, among the clad layers in the double hetero-junction structure, the clad layer closer to said semiconductor substrate and is comprised of a multi-layer structure having different composition ratio, and the layer forming the double-layer and the doublelayer forming the multi-layer structure and closer to the active layer has a wider forbidden band than that of the other layer in the multi-layer (s) structure.
Claim 2
Dependent Claim 161 words
In a light emitting diode made of a compound semiconductor material, comprising: a semiconductor substrate of a first conductivity type; a double hetero-junction structure obtained by sequentially forming at least a clad layer of a first conductivity type, an active layer, and a clad layer of the second conductivity type by a vapor deposition method on the substrate in that order; and a current narrowing structure obtained by selectively forming a contact metal on the clad layer of the second conductivity type in the double hetero-junction structure with an insulating film formed around the contact metal, in which, among the clad layers in the double hetero-junction structure, the clad layer closer to said semiconductor substrate and is comprised of a multi-layer structure having different composition ratio, and the layer forming the double-layer and the doublelayer forming the multi-layer structure and closer to the active layer has a wider forbidden band than that of the other layer in the multi-layer (s) structure.
Claim 3
Dependent Claim 44 words
In a light emitting diode according to claim 1, in which said clad layer closer to the substrate are of a three-layer structure with a layer of a narrower forbidden band width sandwiched between the remaining two layers of a wider forbidden band width.
Claim 4
Dependent Claim 63 words
In a light emitting diode according to claim 1, in which said substrate is comprised of a GaAs substrate, said respective layers are formed of a GaAs/GaAlAs-based material, said clad layer closer to the substrate is formed of Ga 1-x Al x As and the AlAs mole fraction X on the side of the active layer is set to be greater than 0.3.
Claim 5
Dependent Claim 35 words
In a light emitting diode according to claim 1, in which, as in said vapor deposition method, use is made of a metal organic chemical vapor deposition method or a molecular beam epitaxial growth method.
Claim 6
Dependent Claim 39 words
In a light emitting diode according to claim 1, in which in a position corresponding to said contact metal on the substrate a light pick-up window is formed by etching the substrate from the reverse side of the substrate.
Claim 7
Dependent Claim 152 words
In a light emitting diode made of a compound semiconductor material, comprising: a semiconductor substrate of a first conductivity type; a double hetero-junction structure obtained by sequentially forming at least a clad layer of the first conductivity type, an active layer and a clad layer of the second conductivity type by a vapor deposition method on the substrate in that order; and a current narrowing structure obtained by selectively forming a contact metal on the clad layer of the second conductivity type in the double hetero-junction structure with a reverse junction formed around the contact metal, in which, among the clad layers in the double hetero-junction structure, the clad layer closer to said semiconductor substrate is of a multi-layer forming the multi-layer composition ratio, and the layer forming the multi-layer structure and closer to the active layer has a wider forbidden band than that of the other layer(s) in the multi-layer structure.
Claim 8
Dependent Claim 152 words
In a light emitting diode made of a compound semiconductor material, comprising: a semiconductor substrate of a first conductivity type; a double hetero-junction structure obtained by sequentially forming at least a clad layer of the first conductivity type, an active layer and a clad layer of the second conductivity type by a vapor deposition method on the substrate in that order; and a current narrowing structure obtained by selectively forming a contact metal on the clad layer of the second conductivity type in the double hetero-junction structure with a reverse junction formed around the contact metal, in which, among the clad layers in the double hetero-junction structure, the clad layer closer to said semiconductor substrate is of a multi-layer forming the multi-layer composition ratio, and the layer forming the multi-layer structure and closer to the active layer has a wider forbidden band than that of the other layer(s) in the multi-layer structure.
Claim 9
Dependent Claim 43 words
A light emitting diode according to claim 6, in which said clad layer closer to the substrate is of a three-layer structure with a layer of a narrower forbidden band width sandwiched betwen the remaining two layers of a wider forbidden band width.
Claim 10
Dependent Claim 62 words
A light emitting diode according to claim 6, in which said substrate is comprised of a GaAs substrate, said respective layers are formed of a GaAs/GaAlAs-based material, said clad layer closer to the substrate is formed of Ga l-x Al x As and the AlAs mole fraction X on the side of the active layer is set to be greater than 0.3.
Claim 11
Dependent Claim 34 words
A light emitting diode according to claim 6, in which, as in said vapor deposition method, use is made of a metal organic chemical vapor deposition method or a molecular beam epitaxial growth method.
Claim 12
Dependent Claim 38 words
A light emitting diode according to claim 6, in which in a position corresponding to said contact metal on the substrate a light pick-up window is formed by etching the substrate from the reverse side of the substrate.

References Cited (Backward Citations)

US3936855A Cited
US4053914A Cited
US4184170A Cited
US4447822A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-11-09 1991-05-11 1991-11-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-11-09 1995-05-11 1995-11-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-11-09 1999-05-11 1999-11-10 $7700.00 Window Closed / Lapsed

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