SILICON CARBIDE JUNCTION DIODE

• US 3,767,980 A
• Filed: 02/04/1972
• Issued: 10/23/1973
• Est. Priority Date: 07/09/1969
• Status: Expired due to Term

• Current Assignee: Kamath G. Sanjiv
• Original Assignee: Kamath G. Sanjiv
• Inventors: Kamath, G. Sanjiv
• Primary Examiner(s): Edlow, Martin H.
• Application Number:
  US05/223,739
• Time in Patent Office: 627 Days
• Field of Search: 317/235N,235AN,235AQ,237
• US Class Current: 257/77
• CPC Class Codes: C30B 13/02 Zone-melting with a solvent, e.g. travelling solvent process
• CPC Class Codes: C30B 19/04 the solvent being a component of the crystal composition
• CPC Class Codes: C30B 29/36 Carbides
• CPC Class Codes: H01L 29/1608 Silicon carbide
• CPC Class Codes: H01L 33/0054 for devices with an active region comprising only group IV elements
• CPC Class Codes: Y10S 148/107 Melt
• CPC Class Codes: Y10S 148/148 Silicon carbide
• CPC Class Codes: Y10S 438/931 Silicon carbide semiconductor

Abstract

The production of electroluminescent silicon carbide junction diodes is described. These diodes are preferably produced by growth from a silicon carbide or carbon solution in silicon formed between a surface of a p or n-type silicon carbide base crystal and a source of carbon atoms such as a block of solid carbon. The silicon contains one or more p or n-type impurities so that a p-n junction is formed on the crystal. A multistratum epitaxial layer is grown on the base crystal by providing immediately adjacent the base crystal a layer of silicon having one impurity concentration and providing at a remote spot in the reaction zone another mass of silicon having a different impurity concentration. The initial stratum is grown at a relatively low temperature and the second stratum is grown at a higher temperature. The initial stratum can be very thin (less than .0005 inch) and transparent and the second stratum can be opaque and of low resistance due to codoping with boron and aluminum.

Claims

2. A light emitting device capable of emitting light when biased in a forward direction and having a forward resistence (as measured on a 40 mil X 40 mil die) of less than 10 ohms, said device comprising a relatively opaque base crystal of silicon carbide having a predominant p type impurity, a relatively transparent n layer epitaxial with said p base and forminG therewith a light-emitting p-n junction having a characteristic wavelength of emitted light, a second epitaxial layer on said n layer, said second layer having a predominant p type impurity which is different from the predominant p type impurity in said base crystal, said second layer forming a second p-n junction with said n layer which emits light having a characteristic wavelength different from that of the other p-n junction.

3. The device of claim 2 wherein the base crystal contains aluminum as the predominant p type impurity and the epitaxial p layer contains boron as the predominant p type impurity.