| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a normally-off type nitride semiconductor device with a small gate leakage current that is promising as a high-output high-frequency device semiconductor and is for practical use of a high electron mobility transistor (HEMT). <P>SOLUTION: An electron supply layer 3 which is made of an n-type or undoped first nitride semiconductor, and an electron transit layer 4 which forms a heterojunction with the electron supply layer 3, produces a two-dimensional electron gas through by the heterojunction, and has a smaller band gap than the electron supply layer 3, and is made of an undoped second nitride semiconductor are laminated on a substrate 1 with a buffer layer 2 interposed therebetween, and a surface of the electron transit layer 4 laminated on the electron supply layer 3 or a surface of the electron supply layer 4 laminated on the electron transit layer 4 is coated with a cap layer 5 comprising a p-type third nitride semiconductor. A gate electrode 8 is formed on the cap layer 5. <P>COPYRIGHT: (C)2011,JPO&INPIT |
