摘要:
A method of fabricating an enhancement mode semiconductor device comprises providing a compound semiconductor substrate, epitaxially growing on the substrate a first portion of a buffer, the first portion including gallium arsenide (GaAs), growing a second portion of the buffer, the second portion including a high V/III ratio and high aluminum (Al) mole fraction aluminum gallium arsenide (AlGaAs), and epitaxially growing a stack of compound semiconductor layers on the buffer. An enhancement mode semiconductor device is then formed in the stack.