Competition between desorption and diffusion at a GaAs(110) surface

✍ Scribed by A. vom Felde; C.C. Bahr; M.J. Cardillo

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 471 KB
• Volume: 203
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(93)85371-t

✦ Synopsis

We directly demonstrate for NOr on GaAs( 1 lo), using time-resolved modulated molecular beam techniques, that desorption is a competitive rate process with surface diffusion. Using defects as markers, we observe a transition from defect-dominated low coverage chemistry to defect insensitive adsorption/desorption near room temperature. We argue that this competition is generic to adsorbates on semiconductors, in distinct contrast to adsorbates on metal surfaces where diffusion lengths are often large ( z 10' A) for almost all accessible temperatures.