Progress in Epitaxial Oxides on Semiconductors

In this paper, we review the recent progress in the area of epitaxial oxides on semiconductors at Motorola Labs. Critical issues such as surface preparation, initial nucleation and growth behaviors of SrTiO 3 (STO) thin film epitaxy on Si(001) are addressed. Using a systematic approach, high-quality epitaxial STO films are successfully grown on semiconductor substrates such as Si, silicon-on-insulator (SOI) and Ge. Amorphous interfacial layer between the epitaxial STO and the semiconductor can be eliminated or tailored by controlling oxide growth process and parameters. STO-based metal-oxide-semiconductor (MOS) capacitors and transistors are fabricated and tested, in order to explore the potential of STO as high-k gate dielectrics for future generation CMOS transistor technology. In addition, high-quality STO epitaxial films are utilized as thin buffer layers for fabricating integrated oxide heterostructures on semiconductors. Various perovskite oxide films such as SrZrO 3 , LaAlO 3 and Pb(Zr,Ti)O 3 are deposited epitaxially on STO-buffered Si(001) for potential high-k gate dielectrics and surface-acoustic-wave (SAW) device applications.