Cubic Silicon Carbide Substrates

Silicon carbide promises near-term insertion in high power, high temperature, applications. The wide band-gap and consequent high breakdown field of silicon carbide theoretically allows efficient high power solid state power amplifiers. Its high thermal conductivity will permit compact devices and high power density. To date, virtually all silicon carbide-based devices have been fabricated using 6H-SiC; recent advances in bulk and epitaxial 6H-SiC crystal growth have increased its availability. However, 6H-SiC may not be the preferred polytype. The performance of high power and high frequency devices would significantly increase if 3C-SiC, the cubic form, were available. 3C-SiC has twice the electron and hole mobilities of 6H-SiC and has a slightly higher saturation electron drift velocity. In Phase I the feasibility of 3C-SiC substrate growth will be demonstrated with an innovative sublimation crucible design. The objective for Phase II is to optimize the growth of 3C-SiC substrates for device demonstrations. In Phae III, ATM and its partners will scale the crystal growth process to enable the manufacture of specific devices and to supply substrates in order to accelerate the growth of an SiC-based semiconductor industry.