Growth and application of undoped and doped diamond films

Abstract

Diamond is a unique material with several outstanding physical and chemical properties. It has the highest thermal conductivity at room temperature and it is transparent from the UV to the far IR. Furthermore it has the highest hardness, the highest Young's modulus and it is chemically inert and radiation hard. These and other properties of diamond are of great interest for various commercial applications. Much progress has been made in the last decade to produce diamond with chemical vapour deposition (CVD) techniques. Today, CVD diamond plates of more than 10 cm in diameter and more than 1 mm in thickness are commercially available whose properties, especially the optical and thermal ones, are comparable to the best single-crystal diamonds. In this overview, the historical development of CVD diamond deposition with the main focus on the most important techniques, hot-filament and microwave assisted CVD, will be resumed. We describe the control of structural and morphological properties during the deposition which is a prerequisite of oriented growth and the doping of diamond which is needed for semiconductor and sensor applications. The second part of this overview will discuss optical, thermal, thermomechanical and electronic properties of single-crystal diamond and CVD diamond. Finally, we give a description of several applications such as IR windows, heatspreaders, temperature sensors, piezoresistive sensors, diodes and transistors.