| 摘要 |
PROBLEM TO BE SOLVED: To reduce a low-frequency noise of a GaAs field-effect transistor. SOLUTION: This transistor is provided with a semi-insulating GaAs substrate 11, the first, second and third buffer layers 12, 13 and 14, which comprise i-GaAs, i-AlGaAs and i-GaAs, respectively, and epitaxial-formed in this order on the surface of the substrate, and an n-GaAs active layer 15, which is formed on the surface of the buffer layer. In this case, the thickness of the second buffer layer 13 is made equal to or thicker than 0.8μm, so as to reduce the influence of traps, which are formed in relatively large number on an interface between the substrate and the first buffer layer 12. In addition, the thickness of the third buffer layer 14 is also made equal to or thicker than 0.8μm, so as to reduce the influence of traps, which are formed in the second buffer layer 13 and on an interface between the second buffer layer 13 and the third buffer layer 14.
|
