| 摘要 |
PROBLEM TO BE SOLVED: To provide a nitride semiconductor device with superior yield which assures easy control of threshold voltage and has low on-state resistance. SOLUTION: The nitride semiconductor device includes: a first nitride-based semiconductor layer 1 comprising non-doped Al<SB>X</SB>Ga<SB>1-X</SB>N (0≤X<1); a second nitride-based semiconductor layer 2 comprising non-doped or n-type Al<SB>Y</SB>Ga<SB>1-Y</SB>N (0<Y≤1, X<Y) with the lattice constant smaller than that of the first nitride-based semiconductor layer; a third nitride-based semiconductor layer 3 of non-doped or n-type with lattice constant equivalent to that of the first nitride-based semiconductor layer; a fourth nitride-based semiconductor layer 4 comprising In<SB>W</SB>Al<SB>Z</SB>Ga<SB>1-W-Z</SB>N (0<W≤1, 0<Z<1); a gate electrode 5 formed in a recess structure 30 having a bottom surface reaching the third nitride-based semiconductor layer in a gate electrode forming region; and a source electrode 6 and drain electrode 7 formed at any position on the second nitride-based semiconductor layer, third nitride-based semiconductor layer, or fourth nitride-based semiconductor layer where the gate electrode is interposed. COPYRIGHT: (C)2008,JPO&INPIT |
