The chemisorption and reaction of BCl₃ with Si(111)

The chemical mechanisms involved in the decomposition of boron trichloride and the concomitant incorporation of elemental boron into Si(111) were elucidated. The reaction between BCl3 and Si(111) is quit complex due to the presence of Si, B, and Cl in a number of chemically distinct environments simultaneously. Annealing the sample to 570°C effectively desorbs all molecularly adsorbed BCl3. Additional anneals to 710 and 870°C largely reduce the BCl2 and BCl3 moeities to form the subsurface-boron reconstructed surface.