Gallium nitride semiconductor device and preparation method therefor

The invention relates to a gallium nitride semiconductor device and a preparation method therefor. The gallium nitride semiconductor device comprises a substrate, a buffer layer, a high-impedance layer, a non-intentional doped gallium nitride layer, a channel layer and electrodes which are laminated in sequence, wherein the high-impedance layer comprises multiple layers of un-doped gallium nitride layers and carbon-doped gallium nitride layers which are in alternate growth. According to the gallium nitride semiconductor device, for improving breakdown voltage and leakage characteristics, the multiple layers the un-doped gallium nitride layers (Un-doped GaN) and the carbon-doped gallium nitride layers (C-doped GaN) are in crossing growth, so that the quality of the high-impedance layer can be improved, higher growth thickness can be achieved, and bottom rising dislocation bending can be realized. 本发明涉及种氮化镓半导体器件及其制备方法，所述氮化镓半导体器件包括依次层叠的基板、缓冲层、高阻抗层、非有意掺杂氮化镓层、通道层以及电极；所述高阻抗层包括多层交替生长的非掺杂氮化镓层和碳掺杂氮化镓层。该氮化镓半导体器件为了改善击穿电