Optoelectronic semiconductor diodes and devices comprising same

• US 5,925,897 A
• Filed: 02/14/1997
• Issued: 07/20/1999
• Est. Priority Date: 02/14/1997
• Status: Expired due to Term

• Current Assignee: David B. Oberman
• Original Assignee: David B. Oberman
• Inventors: Oberman, David B.
• Primary Examiner(s): GUAY, JOHN FRANCIS
• Application Number:
  US08/800,865
• Time in Patent Office: 886 Days
• Field of Search: 257/88, 257/89, 257/79-80, 257/103, 257/443, 257/448, 257/459, 257/466, 257/99, 257/618, 257/64, 257/75-76, 257/81, 438/34-36, 313/500
• US Class Current: 257/80
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/10253 Silicon [Si]
• CPC Class Codes: H01L 2924/12032 Schottky diode
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/18 within the light emitting region

Abstract

An optoelectronic semiconductor diode is made from a layer of many small individual semiconductor particles containing doping junctions positioned between two contact surfaces mechanically supported by substrates. In the preferred embodiment, the particles are formed of a semiconductor, such as indium gallium nitride, as the active region. The particles are of a size on the order of 10 to 100 microns and are formed by reacting metallic gallium and indium with ammonia, or by a similar method. Electrical contacts are made to the particles by conductive films that have been deposited on the inner surfaces of the substrates. These contacts can be either reflective or transparent, depending upon the materials used. The particles each contain a p-n or similar junction, created either by diffusing in dopants or by selectively activating dopants that are already present. When a forward bias is applied to an LED, minority carriers spill over the junction and recombine with majority carriers to produce light. Powder LEDs according to the present invention can in principle be manufactured to operate at any wavelength within the entire visible spectrum. In addition to light-emitting diodes, the diode design may be adapted to form various types of other optoelectronic diodes such as photodetector and photovoltaic cells. Accordingly, diodes produced according to this design may be used for many applications such as flat panel displays, general purpose lighting, solar cells, and optical communication. They may be fabricated as single diodes or as arrays of diodes having the same or different optical frequency characteristics.

Claims

1. A device comprising an optoelectronic semiconductor diode, wherein the diode comprises:

a first conductive contact,

a second conductive contact, and

a layer of powder sandwiched between the first and second contacts;

wherein the powder comprises doped semiconductor crystal particles.

2. The device of claim 1 wherein the diode further comprises a first plate and a second plate, wherein the first and second plates provide mechanical support for the first and second contacts, respectively.

3. The device of claim 2 wherein the plates are composed of a material chosen from the group consisting of a glass, a metal, and a plastic.

4. The device of claim 1 wherein each of the particles contains a semiconductor junction of a type chosen from the group consisting of p-n, p-i-n, m-i-n, m-i-p, i-n, and i-p.

5. The device of claim 1 wherein the diode emits light in response to an applied electric potential across the first and second contacts due to low-field injection of minority carriers over a doping junction.

6. The device of claim 1 wherein the diode generates an electric potential across the first and second contacts in response to the absorption of light by the particles.

7. The device of claim 1 wherein the diode has a first predetermined optical frequency response, and wherein the device comprises a second diode having a second predetermined optical frequency response distinct from the first predetermined optical frequency response.

8. The device of claim 1 wherein the device is a panel display comprising a plurality of the first conductive contacts, a plurality of the second conductive contacts oriented perpendicular to the first conductive contacts, and a plurality of doped semiconductor crystal particles sandwiched between the first and second contacts.

9. The device of claim 8 wherein the panel display is transparent to optical frequencies of light.

10. The device of claim 9 wherein the panel display comprises a quarter-wave stack mirror, wherein the mirror reflects a specific optical frequency.

11. The device of claim 1 wherein the device is a VLSI chip and the diode provides interchip optical communication.

12. The device of claim 1 wherein each of the particles forms a Schottky barrier with the first contact. wherein the diode generates an electrical potential between the first and second contacts in response to an absorption of light by the powder.

13. The device of claim 1 wherein the particles are composed a semiconductor chosen from the group consisting of a III-V nitride, a III-V arsenide, a II-VI sulfide, and a II-VI selenide.

14. The device of claim 1 wherein the particles are composed of a semiconductor doped with a material chosen from the group consisting of zinc, beryllium, magnesium, carbon, and silicon.

15. The device of claim 1 wherein the particles contain semiconductor junctions having a selectively activated dopant.