Absolute coverage and decomposition kinetics of Mono-, Di-, and tri-hydride phases on Si(111)-(7×7)

Static secondary ion mass spectrometry (SSIMS) is shown to probe directly the coordination of surface silicon atoms to adsorbed hydrogen. Signal intensities of secondary ions, SiD+, SiD2+, and SiD3+ observed in SSIMS following D atom adsorption on Si(111)-(7×7) are proportional to the coverages of SiD, SiD2, and SiD3, respectively. Temperature-programmed desorption is used to quantify the three coverages. The SiD3+ signal in temperature-programmed SSIMS is used to measure the first-order EA (31±2 kcal mol-1) and v (1×1010±1 s-1) for surface SiD3 decomposition. © 1989.