In situ studies of surfaces during chemical vapor deposition using grazing incidence x-ray scattering

Because of the high temperature, chemically-reactive, and near atmospheric pressure operation of most chemical vapor deposition (CVD) processes, there has been limited success in the chemical and physical analysis of these technologically important processes. The usual electron-based probes are not useful, and optical methods can be difficult to interpret. In this work the authors have applied synchrotron-based x-ray techniques to the analysis of the growth of GaAs using organometallic chemical vapor deposition (OMCVD). By monitoring the time and process-dependent intensity of scattered x-rays, at several positions in reciprocal space, they can determine the surface structures such as reconstructions, as well as characterize the surface processes which include island nucleation and growth. Their measurements indicate that despite the overall similarities to UHV-based growth processes, the CVD environment differs in important ways. They discuss the implications of these conclusions