In situ device processing using shadow mask selective area epitaxy and in situ metallization

A concept for in situ device processing has been demonstrated by the fabrication of Au/CdTe device like structures using shadow mask selective area epitaxy (SAE) and in situ metallization. Patterned CdTe epilayers were grown in the molecular beam epitaxy (MBE) chamber using shadow mask SAE (in situ patterning) and then directly transferred within ultrahigh vacuum (UHV) into a metal evaporation chamber for patterned Au deposition (in situ metallization). Excellent pattern definitions of both the CdTe and Au layers were obtained. Good metal adhesion properties and low levels of contamination at the metal-semiconductor interface were observed. A specially designed mask fixture that allows the mask to be placed and removed within the UHV chamber was implemented to perform this work.