Impatt diode

Abstract

Abstract PURPOSE:To provide an IMPATT diode adapted for microwave band and milliwave band by surrounding the junction end of a P-N junction forming the IMPATT diode with a porous SiO2 layer to prevent the variation and deterioration of the characteristics due to outer atmosphere. CONSTITUTION:A P-type layer 2, an N-type region 3 and an N<+>-type layer 4 are laminated and grown on a P<+>-type semiconductor substrate 1, and a P-type impurity is so diffused in the region except the operating pattern thereof as to reach the substrate 1. Then, porosity is formed at the diffused region from the side of this layer 4 with fluoric acid for degassing preliminarily it at approx. 400 deg.C, then heat treating it at 900-1,000 deg.C so as to surround the diffused region with porous SiO2 layer 5a. Thereafter, an upper surface electrode 6 is mounted on the uppermost layer 4 of the operating pattern while extending the electrode 6 over the layer 5a, and a lower surface electrode 7 is coated on the lower surface of the substrate 1. In this manner it is not affected by the outer atmosphere, the floating capacity between the electrode 6 and the layer 5a is reduced, and it can be used for 100GHz band.

Inventors

• 👤 Hiroyuki Nagao

Bibliographic Details