COMPOUND SEMICONDUCTOR EPITAXIAL SUBSTRATE AND METHOD FOR MANUFACTURING SAME

摘要

A compound semiconductor epitaxial substrate having a pseudomorphic high-electron-mobility field-effect transistor structure wherein an InGaAs layer serves as a channel layer (9) and an InGaP layer containing n-type impurities serves as a frontside electron supply layer (12) is disclosed. By growing the epitaxial substrate having the pseudomorphic HEMT structure with an increased In proportion in the channel layer (9), the InGaAs layer has an electron mobility at room temperature (300 K) of 8000 cm2/V.s or higher. Frontside spacer layers (10, 11) between the channel layer (9) and the frontside electron supply layer (12) may be composed of InGaP layers.