In-situ study on thermal decomposition of 1,3-disilabutane to silicon carbide on Si(1 0 0) surface

The intermediates of thermal decomposition of 1,3-disilabutane (SiH3CH2SiH2CH3, DSB) to form SiC on Si(1 0 0) surface were in situ investigated by reactive ion scattering (RIS), temperature programmed reactive ion scattering (TPRIS), temperature programmed desorption (TPD), and auger electron spectroscopy (AES). DSB as a single molecular precursor was exposed on Si(1 0 0) surface at a low temperature less than 100 K, and then the substrate was heated up to 1000 K. RIS, TPD, and AES investigations showed that DSB adsorbed molecularly and decomposed to SiC via some intermediates on Si(1 0 0) surface as substrate temperature increasing. Between 117 and 150 K molecularly adsorbed DSB desorbed partially and decomposed to CH4Si2, which is the first observation on Si(1 0 0) surface, and further decomposed to CH4Si between 150 and 900 K. CH4Si lost hydrogen and formed SiC over 900 K.

Research highlights► Si(1 0 0) surface was exposed to DSB vapor at a temperature less than 100 K and analyzed by the RIS technique. ► Based on the Residual Gas Analysis (RGA) and RIS spectrum, 2 and 89 amu masses were used in Temperature Programmed Desorption for hydrogen and DSB, respectively. Also, based on adspecies identified by RIS and TPRIS at various temperatures, we suggest the decomposition reaction path from DSB to SiC. ► Each carbon peaks were deconvoluted with three species of molecular DSB, graphitic, and carbidic carbon.