Development of single-crystalline diamond wafers : Enlargement of crystal size by microwave plasma CVD and wafer fabrication technology

摘要

Industrial application of diamond has been limited to the use of its hardness, e.g., in machining tools, because large size crystals of diamond are difficult to synthesize and very expensive. If these problems are solved, it can be used for various purposes. Diamond is called 'an ultimate semiconductor' and is located after SiC or GaN in the semiconductor roadmap. If power electronic devices with diamond are realized which utilize its operability under high temperature and the highest thermal conductivity among all materials, the inverters for automobiles can be operated without cooling devices, which lead to energy saving through the reduction of power loss as well as the reduction of weight of the cooling system. The purpose of this paper is to report the process of enlarging the size of single-crystalline diamond using vapor phase epitaxy and the fabrication of diamond wafers.