Transistor

Patent Granted PROBLEM TO BE SOLVED: To improve charge matching performance and grid matching performance on a channel layer interface in a transistor using zinc oxide as a channel layer. ; SOLUTION: Zinc oxide is epitaxial grown on a buffer layer 3 formed on a substrate 2, and a channel layer is formed. Furthermore, Mg<SB>1-x</SB>Ca<SB>x</SB>O is epitaxially grown on the channel layer 4 so that an interface modification layer 7 can be formed, and a gate insulating layer 8 and a gate electrode 9 are formed through the interface modification layer 7.