Selective epitaxy of compound semiconductors: novel sources

Abstract

The development of selective epitaxial techniques has centred on the use of conventional precursors such as trimethyl gallium in combination with AsH3. Recently, the development of new precursors, such as diethyl gallium chloride, or the use of conventional precursors in conjunction with HCl or AsCl3 has offered greater flexibility in the development of a selective-area epitaxial process. In addition, wide process windows have been demonstrated whereby excellent material properties and high selectivity can be achieved under typical MOVPE conditions. This compatibility with conventional MOVPE growth conditions allows for the integration of selective-area growth into the existing MOVPE growth processes. This paper will present recent results on the development of these alternative precursors for selective-area growth. The achievement of a selective epitaxial process is discussed in terms of the chemistry of the inorganic-based growth techniques.