TY - JOUR
T1 - Si(001):B gas-source molecular-beam epitaxy
T2 - Boron surface segregation and its effect on film growth kinetics
AU - Kim, H.
AU - Glass, G.
AU - Spila, T.
AU - Taylor, N.
AU - Park, S. Y.
AU - Abelson, J. R.
AU - Greene, J. E.
PY - 1997/9/1
Y1 - 1997/9/1
N2 - B-doped Si(001) films, with concentrations CB up to 1.7 × 1022 cm-3, were grown by gas-source molecular-beam epitaxy from Si2H6 and B2H6 at Ts = 500-800°C. D2 temperature-programed desorption (TPD) spectra were then used to determine B coverages θB as a function of CB and Ts. In these measurements, as-deposited films were flash heated to desorb surface hydrogen, cooled, and exposed to atomic deuterium until saturation coverage. Strong B surface segregation was observed with surface-to-bulk B concentration ratios ranging up to 1200. TPD spectra exhibited β2 and β1 peaks associated with dideuteride and monodeuteride desorption as well as lower-temperature B-induced peaks β*2 and β*1. Increasing θB increased the area under β*2 and β*1 at the expense of β2 and β1 and decreased the total D coverage θD. The TPD results were used to determine the B segregation enthalpy, -0.53 eV, and to explain and model the effects of high B coverages on Si(001) growth kinetics. Film deposition rates R increase by ≥50% with increasing CB≳1 × 1019 cm-3 at Ts≤550°C, due primarily to increased H desorption rates from B-backbonded Si adatoms, and decrease by corresponding amounts at Ts≥600°C due to decreased adsorption site densities. At Ts≥700°C, high B coverages also induce {113} facetting.
AB - B-doped Si(001) films, with concentrations CB up to 1.7 × 1022 cm-3, were grown by gas-source molecular-beam epitaxy from Si2H6 and B2H6 at Ts = 500-800°C. D2 temperature-programed desorption (TPD) spectra were then used to determine B coverages θB as a function of CB and Ts. In these measurements, as-deposited films were flash heated to desorb surface hydrogen, cooled, and exposed to atomic deuterium until saturation coverage. Strong B surface segregation was observed with surface-to-bulk B concentration ratios ranging up to 1200. TPD spectra exhibited β2 and β1 peaks associated with dideuteride and monodeuteride desorption as well as lower-temperature B-induced peaks β*2 and β*1. Increasing θB increased the area under β*2 and β*1 at the expense of β2 and β1 and decreased the total D coverage θD. The TPD results were used to determine the B segregation enthalpy, -0.53 eV, and to explain and model the effects of high B coverages on Si(001) growth kinetics. Film deposition rates R increase by ≥50% with increasing CB≳1 × 1019 cm-3 at Ts≤550°C, due primarily to increased H desorption rates from B-backbonded Si adatoms, and decrease by corresponding amounts at Ts≥600°C due to decreased adsorption site densities. At Ts≥700°C, high B coverages also induce {113} facetting.
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U2 - 10.1063/1.366036
DO - 10.1063/1.366036
M3 - Article
AN - SCOPUS:0000676313
SN - 0021-8979
VL - 82
SP - 2288
EP - 2297
JO - Journal of Applied Physics
JF - Journal of Applied Physics
IS - 5
ER -