| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a nitride semiconductor substrate which inhibits current collapse while achieving reduction in leakage current and which is suitable for a high-voltage power device.SOLUTION: In a nitride semiconductor substrate in which a buffer layer 2, an active layer 3 and an electron supply layer 4, which are composed of group 13 nitride and sequentially laminated on a silicon single crystal substrate 1, the buffer layer 2 includes a structure in which double layers 23 formed by repeatedly depositing a pair of nitride layers having different compositions of Al or Ga a plurality of times are laminated on an initial layer 22 composed of AlGaN(0≤x≤1), and includes a doping layer 21 having a carbon concentration of 1×10-1×10cmand a Si concentration of 1×10-1×10cm. A thickness of the doping layer 21 is not less than 15% of a thickness of the entire buffer layer 2.</p> |
