BETA-SIC FILMS ON SOI SUBSTRATES FOR HIGH-TEMPERATURE APPLICATIONS

Single crystalline, cubic beta-SiC films were deposited by CREE Inc., USA on bonded SOI wafers. The SiC deposition took place under standard conditions used at CREE for deposition on Si wafers, and at depositio n temperatures 25 degrees C and 50 degrees C below standard deposition conditions to investigate the influence of the deposition temperature on the damage of the buried oxide layer and therefore the insulating capability of that layer. Transmission electron microscopy (TEM), atom ic force microscopy (AFM) and optical microscopy were used for structu ral analysis of the Silicon Carbide On Insulator (SiCOI) structure. Th e deposited beta-SiC films. the buried SiO2 layer, and the SiC/Si inte rface were investigated. First measurements showed similar results for all three deposition temperatures indicating that the deposition temp erature is not the only parameter defining the structural and therefor e also the electrical quality of the SiCOI wafers. The electrical meas urements were performed up to T = 723 K (current limit of the equipmen t) and the results showed good electrical insulation of the SiC layer from the Si substrate in the whole temperature range. (C) 1997 Elsevie r Science S.A.