| 摘要 |
This field-effect transistor is provided with: a co-doped layer, which is formed of AlxGa1-xN (0≤x≤1) on a p type Si substrate; a GaN layer formed on the co-doped layer; and an AlGaN layer formed on the GaN layer. The co-doped layer contains C and Si as impurity elements, an impurity concentration of C in the co-doped layer is 5×1017/cm3 or more, an impurity concentration of Si in the co-doped layer is lower than the impurity concentration of C, an impurity concentration of C in the GaN layer is 1×1017/cm3 or less, and a film thickness of the GaN layer is 0.75 μm or more. |
