Hydrogen desorption kinetics from epitaxially grown Si(100)

Abstract

The kinetics for the desorption of H2 from silicon are examined. The hydrogen coverage is generated during silicon epitaxy using SiH4 in a rapid thermal chemical vapor deposition reactor. The hydrogen coverage could be "frozen out" completely on the surface by the rapid cooldown and pump down of the reactor up to temperatures of about 845 K. The activation energy for the desorption of hydrogen is 49±3 kcal mol-1 and the pre-exponential for desorption is 8×1013±1 s -1. The presence of defect sites due to quenching the growth may influence the subsequent desorption kinetics of H2.