摘要 |
To provide a transistor device, which is composed of a compound semiconductor, having a multilayer structure in which a high electron mobility transistor (HEMT) and a heterojunction bipolar transistor (HBT) are overlapped on the same substrate and epitaxial-grown thereon, wherein a band gap energy of an indium gallium phosphide layer (InGaP) included in an epitaxial layer, is set to 1.91 eV or more. |