发明名称 Protection circuit including vertical gallium nitride schottky diode and PN junction diode
摘要 A circuit includes a vertical conduction gallium nitride-based Schottky diode and a vertical conduction silicon based PN junction diode connected in parallel. The Schottky diode and the PN junction diode are packaged in the same semiconductor package and the PN junction diode does not conduct in response to the Schottky diode being forward biased. In some embodiments, the silicon based PN junction diode has a breakdown voltage lower than a breakdown voltage of the gallium nitride-based Schottky diode. The silicon based PN junction diode enters breakdown in response to the gallium nitride-based Schottky diode being reverse biased to divert a reverse bias avalanche current away from the gallium nitride-based Schottky diode.
申请公布号 US9406661(B2) 申请公布日期 2016.08.02
申请号 US201514632352 申请日期 2015.02.26
申请人 Alpha and Omega Semiconductor Incorporated 发明人 Zhu TingGang;Bhalla Anup;Huang Ping;Ho Yueh-Se
分类号 H01L25/18;H01L29/66;H01L29/872;H01L29/861;H01L29/20;H01L29/40;H01L23/00 主分类号 H01L25/18
代理机构 Van Pelt, Yi & James LLP 代理人 Van Pelt, Yi & James LLP
主权项 1. A circuit comprising: a vertical conduction gallium nitride-based Schottky diode, the Schottky diode having an anode electrode formed on a front side of a nitride-based semiconductor body and a cathode electrode formed on a backside of the nitride-based semiconductor body, the vertical conduction gallium nitride-based Schottky diode comprising: a nitride-based semiconductor body of a first conductivity type;a first metal layer formed on a front side of the nitride-based semiconductor body forming a Schottky junction therewith, the first metal layer forming the anode electrode of the Schottky diode;a second metal layer formed on the first metal layer;a third metal layer formed on a backside of the nitride-based semiconductor body, the third metal layer forming an ohmic contact with the semiconductor body and forming the cathode electrode of the Schottky diode;a termination structure formed at an edge of the first metal layer, the termination structure being configured to reduce electric field crowding at the edge of the anode electrode, wherein the termination structure comprises a guard ring comprising a nitride-based epitaxial layer of a second conductivity type, opposite the first conductivity type, formed on the front side of the nitride-based semiconductor body at the edge of the first metal layer, the nitride-based epitaxial layer having a step recess where the part of the epitaxial layer having a thinner thickness is disposed towards the Schottky junction of the Schottky diode; and a dielectric field plate formed on a top surface of the nitride-based epitaxial layer, the dielectric field plate extending up to the step recess of the nitride-based epitaxial layer;a solder ball formed on the second metal layer; anda wafer level molding layer formed on the front side of the nitride-based semiconductor body, the wafer level molding layer encapsulating the second metal layer and at least part of the solder ball,wherein the Schottky diode has a vertical current path from the solder ball, through the anode electrode and the Schottky junction to the cathode electrode; and a vertical conduction silicon based PN junction diode, the PN junction diode having an anode electrode electrically connected to the anode electrode of the Schottky diode and a cathode electrode electrically connected to the cathode electrode of the Schottky diode, wherein the Schottky diode and the PN junction diode are packaged in the same semiconductor package and the PN junction diode does not conduct in response to the Schottky diode being forward biased.
地址 Sunnyvale CA US