| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide SiC MESFETs with reduced back-gating effects by forming MESFETs on a semi-insulating SiC substrate which substantially free of deep-level dopants. <P>SOLUTION: A selectively doped P-type silicon carbide layer 13 and an N-type epitaxial layer 14 are laminated on a semi-insulating substrate 10 to reduce back-gating effects. A gate structure having two recessed parts is provided. Thereby, output conductance can be reduced to one-third, and a 3 db increase in power gain can be produced. Chromium 42 can be utilized as a Schottky gate contact. Furthermore, an oxide-nitride-oxide (ONO) protective layer 60 is utilized to reduce surface effects in MESFETs. Also, source and drain ohmic contacts may be formed directly on the n-type channel layer, thus, the n<SP POS="POST">+</SP>regions need not to be fabricated. <P>COPYRIGHT: (C)2012,JPO&INPIT |
