上海科技大学知识管理系统

本发明了一种垂直型氮化镓肖特基二极管器件及其制备方法。所述器件包括阳极金属层、铝镓氮层、N型轻掺杂层、N型重掺杂层、缓冲层、衬底及阴极金属层。制备方法为：在衬底表面沉积一层缓冲层，在缓冲层上形成N型重掺杂层、N型轻掺杂层；刻蚀部分N型轻掺杂层，在N型轻掺杂层中刻蚀凹槽，并沉积铝镓氮层；继续沉积阳极金属层；在N型重掺杂层或衬底表面沉积阴极金属层。本发明提供的氮化镓肖特基二极管器件较现有的横向平面型和垂直型氮化镓肖特基二极管具有更强的抗击穿能力，该器件正向导通时，减少串联电阻进而减少发热，有利于防止热逃逸现象；当处于反向偏压条件下时，电场的峰值处于铝镓氮层中，增加器件反向耐压特性。

The invention relates to a vertical GaN Schottky diode device and a preparation method thereof. The device comprises an anode metal layer, an Al-Ga-N layer, an N-type lightly doped layer, an N-type heavily doped layer, a buffer layer, a substrate and a cathode metal layer. The preparation method includes the following steps : depositing a buffer layer on the surface of a substrate, and forming an N-type heavily doped layer and an N-type lightly doped layer on the buffer layer; etching part of the N-type lightly doped layer to form a groove in the N-type lightly doped layer, and depositing an Al-Ga-N layer; continuing to deposit an anode metal layer; and depositing a cathode metal layer on the surface of the N-type heavily doped layer or the substrate. The GaN Schottky diode device providedby the invention has stronger breakdown resistance than the existing transverse planar and vertical GaN Schottky diodes. When the device is forwardly switched on, the series resistance is reduced andless heat is emitted, which is beneficial to the prevention of the phenomenon of heat escape. When the device is under a reverse bias voltage condition, the peak of the electric field is in the Al-Ga-N layer, which increases the reverse voltage withstanding characteristic of the device.