| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor device having an easy-to-fabricate HEMT capable of performing an enhancement-mode operation, and also to provide a method of fabricating the device. <P>SOLUTION: In a nitride-based semiconductor, the height of a Schottky barrierΦ<SB>B</SB>markedly changes with respect to the work function of a metalΦ<SB>M</SB>, unlike GaAs and Si. Thus, in the HEMT having a buffer layer 2 and a barrier layer 3 made of the nitride-based semiconductor successively formed on a substrate 1 with a gate electrode 4 formed on the buffer layer 3, for example, the enhancement-mode operation is enabled by selecting a metal of a comparatively high work functionΦ<SB>M</SB>as a metal that makes up the gate electrode 4 and adjusting the thickness of the barrier layer 3 so as to render the height of a Schottky barrierΦ<SB>B</SB>high as compared with the surface potentialΦ<SB>S</SB>of the semiconductor on both sides of the gate electrode 4, because secondary electron gas is blocked from existing under the gate electrode 4 without forming a recess in the region of the barrier layer 3 immediately under the gate electrode 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
