Nitride semiconductor element and method of manufacturing the same

摘要

A nitride semiconductor element having a high reverse breakdown voltage and a method of manufacturing the same are provided. A diode (a vertical-type SBD) has an n−-type nitride semiconductor layer (a drift region) formed on an n-type nitride semiconductor substrate, a p-type nitride semiconductor layer formed on the n−-type nitride semiconductor layer, and besides, an anode electrode formed on the p-type nitride semiconductor layer. The p-type nitride semiconductor layer has a relatively-thin first portion and a relatively-thick second portion provided so as to surround the first portion as being in contact with an outer circumference of the first portion. Also, the relatively-thin first portion of the p-type nitride semiconductor layer is formed thinner than the second portion so as to be depleted. The relatively-thick second portion of the p-type nitride semiconductor layer forms a guard ring part.

主权项

1. A nitride semiconductor element comprising:
a nitride semiconductor substrate of a first conductive type, the nitride semiconductor substrate having a first surface and a second surface on a back side of the first surface; a nitride semiconductor layer of the first conductive type provided on the first surface side of the nitride semiconductor substrate of the first conductive type; a nitride semiconductor layer of a second conductive type, provided on the nitride semiconductor layer of the first conductive type, having a first portion and a second portion provided so as to surround the first portion, and set as having a conductive type opposite to the first conductive type; a first electrode having a portion connected with the first portion in a state of a Schottky junction and a portion connected with the second portion in a state of an ohmic junction; and a second electrode provided on the second surface side of the nitride semiconductor substrate of the first conductive type, and a film thickness of the first portion being thinner than a film thickness of the second portion so as to be depleted.