SEMICONDUCTOR DEVICE AND POWER AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device and power amplifier capable of improving current drive capability while ensuring a low-voltage operation.SOLUTION: The semiconductor device with a bipolar transistor BT is configured so that an n-type collector layer 4 is a two-layer structure of a first collector layer 4a of n-type GaAs including gallium arsenide (GaAs) and a second collector layer 4b (GaN molar ratio: 0.018) of n-type GaAsN including nitriding gallium arsenide (GaAsN), and is formed with a p-type Ge base layer 5 including germanium (Ge) to be in contact with the second collector layer 4b of n-type GaAsN.