Hydrogen radical processing-in-situ semiconductor surface cleaning for epitaxial regrowth

The achievement of high-quality interfaces for improved semiconductor device structures necessitates in-situ surface cleaning between different material deposition processes. In this contribution in-situ hydrogen radical exposure is presented as an advanced technique to obtain semiconductor surfaces adequate for MBE regrowth. Exposure of InP-based materials to a thermal hydrogen radical beam at relatively low temperatures removes the native oxide layer from GaInAsP as well as AlGaInAs. In addition, accumulation of carbon, being the most prominent contaminant due to the exposure to air or intermediate ex-situ processing steps, is efficiently reduced. There is no indication of the occurrence of degradation of the treated material due to the hydrogen radical process which makes it especially suited for the fabrication of complex device structures.