SiC/Si heterojunction diodes fabricated by self-selective and by blanket rapid thermal chemical vapor deposition

SiC/Si heterojunction diodes have been fabricated by two different rapid thermal chemical vapor deposition (RTCVD) processes: a localized self-selective growth and blanket growth. The self-selective growth of crystalline cubic (/spl beta/) SiC was obtained by propane carbonization of the Si substrate in regions unprotected by an SiO/sub 2/ layer, producing planar diodes. Mesa diodes were fabricated using the blanket growth of polycrystalline /spl beta/-SiC produced by the decomposition of methylsilane (CH/sub 3/SiH/sub 3/). The SiC/Si heterojunction diodes show good rectifying properties for both device structures. Reverse breakdown voltage of 50 V was obtained with the self-selective SiC/Si diode. The mesa diodes exhibited even higher breakdown voltages (V/sub br/) of 150 V and excellent ideality factors of 1.06 at 25/spl deg/C. The high V/sub br/ and good forward rectifying characteristics indicate that the SiC/Si heterojunction diode represents a promising approach for the fabrication of wide-gap emitter SiC/Si heterojunction bipolar transistors.<
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