AVS 49th International Symposium
    Surface Science Thursday Sessions
       Session SS+EL-ThA

Paper SS+EL-ThA3
Si Deposition on H-terminated Si(100) Surfaces@footnote *@

Thursday, November 7, 2002, 2:40 pm, Room C-112C

Session: Growth & Etching on Semiconductor Surfaces
Presenter: J.-Y. Ji, Utah State University
Authors: J.-Y. Ji, Utah State University
T.T. Barus, Utah State University
T.-C. Shen, Utah State University
G. Qian, University of Illinois at Urbana-Champaign
X. Luo, National Renewable Energy Laboratory
S. Ren, Illinois State University
S. Zhang, National Renewable Energy Laboratory
Y.C. Chang, University of Illinois at Urbana-Champaign
Correspondent: Click to Email
The presence of H has long been considered adverse to Si homoepitaxy. Copel and Tromp@footnote 1@ reported that while no apparent effect on epitaxy was observed at H coverage <1 ML and H segregates at growth temperature >400 K, a drastic epitaxial temperature increase was required at H coverage >1 ML. We will present the results of our STM, and first principle molecular dynamics studies on Si monohydride and dihydride effect in Si epitaxy. We confirmed that at growth temperatures ~ 500 K, H stays on the growth front on monohydride surfaces and epitaxy can be achieved but the domain sizes are much smaller than those grown on the bare Si. Continuous rebonding apparently is responsible for the epitaxial growth on Si monohydride surfaces. The diffusion barrier for the Si adatom along the Si monohydride dimer rows is calculated to be 1.1 eV which is significantly higher than the corresponding 0.6 eV barrier on the bare Si(100)-2x1 surface. To account for the H segregation, a mechanism to exchange H atoms between a surface Si atom and the incident Si atom is proposed. The experimental and theoretical result on the dihydride effect will be discussed. @FootnoteText@ @footnote *@This work is supported by NSF-DMR9875129, ARDA/ARO DAAD 19-00-1-0407 and DARPA-QuIST DAAD 19-01-1-0324.@footnote 1@M. Copel and R. M. Tromp, Phys. Rev. Lett. 72, 1236 (1994).