抄録
Polymethylsilane (PMS) modified with titanium chloride (TiCl4) or molybdenum chloride (MoCl5) was pyrolyzed at various temperatures to enable a detailed investigation of stable phases formed during pyrolysis. The existence of TiSi2 in PMS-TiCl4 precursor and β-MoSi2 in the PMS-MoCl5 precursor below 1273 K suggested a strong interaction between Si-H and the metal chlorides during mixing. During pyrolysis of the PMS-10 mass% TiCl4 precursor, a silicon rich Si-Ti-C state was obtained below 973 K, which simultaneously formed crystalline Si, TiSi2, and SiC phases at relatively low temperatures below 1273 K. During pyrolysis of the PMS-MoCl5 precursors, however, formation of crystalline Si and SiC phases were not accelerated, while the crystalline β-MoSi2 or α-MoSi2 phase was formed rapidly.
