KINETIC-ANALYSIS IN LASER PYROLYSIS OF SI(CH3)2CL2

Chemical kinetics of the laser pyrolysis of Si(CH3)2Cl2 was studied at pressures of 135, 107 and 84 torr using 1 to 4 W laser radiation (488 nm). The gaseous products were H-2 and HCl; also black cylindrical ro ds SiC(x) (X=0.3 to 1.2) were deposited. The decomposition of Si(CH3)2 Cl2 was found to be a first order reaction. The rate constants of the decomposition of Si(CH3)2Cl2 and the rate constants of formation of H- 2 and HCl were measured. Activation energy was estimated to be 44.3 kJ mol-1. The initial reaction in this laser pyrolysis removes H-2 and H CI from Si(CH3)2Cl2. A model for this pyrolysis was suggested. Many pa rameters were calculated to illustrate the detailed picture of the pyr olysis.