Abstract
The thermal decomposition processes of phosphine (PH 3 ) on a Ge(1 0 0)-2 × 1 surface at temperatures between 325 and 790 K were investigated and compared with those on Si(1 0 0)-2 × 1. High-resolution synchrotron radiation core-level photoemission spectra indicates that, at room temperature phosphine molecularly adsorbs on the Ge(1 0 0)-2 × 1 surface, however on the Si(1 0 0)-2 × 1 it partially dissociates into PH 2 and H. Successive annealing of the PH 3 -saturated Si(1 0 0) and Ge(1 0 0) surfaces at higher temperatures similarly converts PH 3 into PH 2 and PH 2 to P. P atoms form stable P-P and/or P-Si dimers on Si(1 0 0) above 720 K, but exhibit complex bonding configurations on Ge(1 0 0). © 2001 Elsevier Science B.V.