Developments in CVD delivery systems: A chemist's perspective on the chemical and physical interactions between precursors

Important factors in considering compounds for use as precursors in CVD techniques are discussed. Conventionally, volatility along with precursor purity and clean decomposition to the desired materials, are all regarded as crucial precursor properties. Recent developments in the way in which precursors are delivered into the vapor phase mean volatility is no longer such an important requirement. Less volatile precursors with better deposition routes are now routinely employed. In this review, a description of the fundamentally new approaches to CVD delivery systems developed in recent years is presented. Examples highlighting the importance of understanding both the chemical and physical interactions between different precursors, and also those between the carrier gases and precursors, are discussed.