Heterojunction field effect type semiconductor device having high gate turn-on voltage and low on-resistance and its manufacturing method

摘要

In a heterojunction field effect type semiconductor device, a channel layer (5, 5') is formed over a GaAs substrate (1), and a first semiconductor layer including no aluminum is formed over the channel layer (9, 9'). First and second cap layers (11, 11', 11a', 11b') of a first conductivity type are formed on the first semiconductor layer, to create a recess (11a) on the first semiconductor layer. First and second ohmic electrodes (14S, 14D) are formed on the first and second cap layers, respectively. A second semiconductor layer (15, 15', 15") of a second conductivity type is formed on the first semiconductor layer within the recess, and the semiconductor layer is isolated from the first and second cap layers. A gate electrode (13) is formed on the second semiconductor layer.