Patent ID: 7816733
Filing Date: 2010-10-19
Classification: H01L

Abstract:
1. A semiconductor device having a junction barrier Schottky diode comprising: a SiC substrate having a first conductive type and including first and second surfaces; a drift layer having the first conductive type, disposed on the first surface of the substrate, made of SiC, and having an impurity concentration, which is lower than that of the substrate; an insulation film disposed on the drift layer and having an opening in a cell region; a Schottky barrier diode having a Schottky electrode and an ohmic electrode, wherein the Schottky electrode is disposed in the cell region and contacts the drift layer through the opening of the insulation film with Schottky contact, and wherein the ohmic electrode is disposed on the second surface of the substrate; a terminal structure having a RESURF layer and disposed on an outer periphery of the cell region, wherein the RESURF layer has a second conductive type, surrounds the cell region, and is disposed in a surface portion of the drift layer; and a plurality of second conductive type layers, each of which is disposed in another surface portion of the drift layer on an inner side of the RESURF layer, contacts the Schottky electrode, wherein the second conductive type layers are separated from each other by a predetermined distance, wherein: the plurality of second conductive type layers and the drift layer provide a PN diode; each second conductive type layer has a depth, which is larger than a depth of the RESURF layer; the plurality of second conductive type layers includes a first layer and a second layer; the first layer is disposed in a center portion of the cell region, and the second layer is disposed in an outside portion of the cell region; and the first layer has a depth, which is larger than a depth of the second layer.