| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To achieve a MIS structure HFET, using a nitride semiconductor, which reduces a gate leakage current more effectively and improves device reliability during application of a large gate voltage. <P>SOLUTION: In the heterostructure field-effect transistor having a gate insulating film between the nitride semiconductor 1 and a gate electrode 3, the gate insulating film comprises a first insulating film 6 close to the nitride semiconductor 1 and a second insulating film 7 close to the gate electrode 3 as components, the first insulating film 6 is an insulating film of 4 to 200 nm in thickness made of an insulator of≥20 in dielectric constant, for example, HfO<SB>2</SB>, HfAlO, HfON, and ZrO<SB>2</SB>, and the second insulating film 7 is an insulating film which is made of SiO<SB>2</SB>or Al<SB>2</SB>O<SB>3</SB>and≥2 nm thick and is smaller in film thickness than the first insulating film 6. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
