Power amplifier circuit and semiconductor device

A power amplifier circuit comprising:

• a first transistor disposed on a semiconductor substrate;
• a bias circuit configured to be supplied with a control current and to supply a bias current based on the control current to the first transistor;
• a first metal member electrically connected to an emitter of the first transistor, said first metal member being disposed to overlap a first disposition area in which the first transistor is disposed in plan view of the semiconductor substrate;
• a control circuit connected to the bias circuit and configured to supply the control current to the bias circuit;
• a diode disposed on the semiconductor substrate and having an anode connected to the control circuit and a cathode connected to ground;
• and
• a third metal member disposed to overlap a third disposition area in which the diode is disposed in the plan view, wherein
• the control circuit is configured to detect a characteristic variation of the diode and supply the control current controlled in accordance with the characteristic variation to the bias circuit.