Unit of light emitting diode arrays

• US 4,633,280 A
• Filed: 07/10/1985
• Issued: 12/30/1986
• Est. Priority Date: 07/20/1984
• Status: Expired due to Term

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation), Tottori Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation), Tottori Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Takasu, Hiromi
• Primary Examiner(s): Davie, James W.
• Assistant Examiner(s): Epps, Georgia Y.
• Application Number:
  US06/753,393
• Time in Patent Office: 538 Days
• Field of Search: 357/17, 357/16, 357/45, 357/65, 357/68, 357/20, 313/498, 313/499, 313/500, 313/510, 354/5, 354/12
• US Class Current: 257/91
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48472 the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• CPC Class Codes: H01L 27/153 in a repetitive configuration, e.g. LED bars
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H01L 33/0062 for devices with an active region comprising only III-V compounds
• CPC Class Codes: H01L 33/30 containing only elements of Group III and Group V of the Periodic Table
• CPC Class Codes: H01L 33/385 the electrode extending at least partially onto a side surface of the semiconductor body
• CPC Class Codes: H01L 33/40 Materials therefor
• CPC Class Codes: Y10S 257/926 Elongated lead extending axially through another elongated lead

Abstract

A unit of light emitting diode arrays in accordance with the present invention comprises a main body (21) of n-GaAs, layers (22) and (23) of n-GaAsP formed on the main body and a plurality of light emitting regions (24) formed in a line by diffusion of Zn on the surface of the layers. Each of the light emitting regions (24) has a rectangular shape and contains a protruding portion (241). In the direction intersecting at right angles with the light emitting regions (24) formed in a line, electrodes (25) are provided alternately. These electrodes (25) are formed by evaporation and photolithography to cover the respective protruding portions (241) so as to be in ohmic contact. Thus, since the electrodes (25) are formed to cover the protruding portions (241) of the light emitting regions (24), a printing dot of a desired shape can be formed and accordingly, the quality of printing can be improved and an arrangement of a high density of printing dots can be made.

Claims

1. A unit of light emitting diode arrays comprising:

a substrate of a first conductivity type;

a plurality of regions of a second conductivity type formed in the surface of said substrate to emit light corresponding to a dot shape, each of said plurality of regions including a dot-shaped portion and a portion protruding laterally to the dot-shaped portion having narrower width than the dot-shaped portion; and

light intercepting electrodes in ohmic contact covering partially said respective protruding portions of the second conductivity type.

2. A unit of light emitting diode arrays in accordance with claim 1, wherein

said substrate of the first conductivity type is an n type substrate and said plurality of regions of the second conductive type are P type regions.

3. A unit of light emitting diode arrays in accordance with claim 2, wherein

said n type substrate is a n-GaAsP substrate.

4. A unit of light emitting diode arrays in accordance with claim 2, wherein

said n type substrate comprises a main body formed of GaAs and layers of n-GaAsP formed in said main body.

5. A unit of light emitting diode arrays in accordance with claim 1, wherein

said plurality of regions of the second conductivity type are arrayed in a line.

6. A unit of light emitting diode arrays in accordance with claim 3, wherein

said plurality of regions of the second conductivity type are formed by diffusion of Zn in said n-GaAsP substrate.

7. A unit of light emitting diode arrays in accordance with claim 4, wherein

said plurality of regions of the second conductivity type are formed by diffusion of Zn in said n-GaAsP layers.

8. A unit of light emitting diode arrays in accordance with claim 1, wherein

said dot shape has an square shape having four sides, and

said plurality of regions of the second conductivity type each correspond to said angular shape and each have one side including said protruding portion.

9. A unit of light emitting diode arrays in accordance with claim 8, wherein

said square shape is a parallelogram.

10. A unit of light emitting diode arrays in accordance with claim 8, wherein

said square shape is rectangular.

11. A unit of light emitting diode arrays in accordance with claim 1, wherein

said dot shape has a circular shape , and

said plurality of regions of the second conductivity type each correspond to said circular shape and each have a portion including said protruding portion extending therefrom.

12. A unit of light emitting diode arrays in accordance with claim 1, wherein

said each electrode includes a portion covering said protruding portion so that a light emitting pattern from said each region has a shape similar to said dot shape.

13. A unit of light emitting diode arrays in accordance with claim 1, wherein

said electrodes are formed to extend alternately in the direction intersecting at right angles with said plurality of regions of the second conductivity type arrayed in a line.