Plasma assisted process for deposition of silicon carbide thin films

Abstract

Abstract Silicon carbide (SiC) thin films were deposited on silicon substrate by the RF plasma chemical method, operating at a frequency of 13.56 MHz. Two different plasma assisted chemical vapor deposition (CVD) technologies were attempted: direct plasma CVD with reaction gas of CH 3 SiCl 3 and remote plasma CVD with SiH 4 + C 3 H 8 . The film deposition rate of SiC was linearly increased with the plasma power when the substrate temperature was fixed to 300 °C. The measurement of the photon absorption reveals that the band gaps of the electron energy state were to be 2.39 eV for Si 0.5 C 0.5 , and 2.51 eV for Si 0.4 C 0.6 , respectively. In the high-density regime of the RF plasma, the methyl-radicals decompose easily and increase the carbon concentration in the plasma and result in the growing films. The yield of the remote plasma CVD was estimated as 70.8% when the flow rate of SiH 4 + C 3 H 8 gases was kept to 15SCCM and 10SCCM, respectively. The deposition of SiC films with remote plasma CVD followed by a laser treatment would be the optimal process technology to obtain the high quality poly-crystalline SiC film.