Method for manufacturing compound semiconductor device
A semiconductor layer ( 2,3 ) is provided on a substrate ( 1 ). A gate electrode ( 4 ), a source electrode ( 5 ) and a drain electrode ( 6 ) are provided on the semiconductor layer ( 3 ). A first passivation film ( 7 ) covers the gate electrode ( 4 ) and the semiconductor layer ( 3 ). A source field plate ( 9 ) is provided on the first passivation film ( 7 ), and extends from the source electrode ( 5 ) to a space between the gate electrode ( 4 ) and the drain electrode ( 6 ). A second passivation film ( 10 ) covers the first passivation film ( 7 ) and the source field plate ( 9 ). An end portion on the drain electrode ( 6 ) side of the source field plate ( 9 ) is curved to be rounded.
1. A method for manufacturing a compound semiconductor device comprising:
forming a semiconductor layer on a substrate;
forming a gate electrode, a source electrode and a drain electrode on the semiconductor layer;
forming a first passivation film covering the gate electrode and the semiconductor layer;
forming a resist extending from the drain electrode to a space between the gate electrode and the drain electrode on the first passivation film;
forming a conductive film on the first passivation film and the resist;
removing the resist and the conductive film on the resist to form a source field plate; and
forming a second passivation film covering the first passivation film and the source field plate, wherein when the resist is formed, a heat treatment is performed to shrink the resist so that a side surface of the resist is thermally drooped in a concave shape.