Toroidal Plasma CVD Growth of Large Area Single Crystal Diamond Wafers

In this program we will develop a means to fabricate single crystal diamond wafers using a newly-designed toroidal plasma reactor that offers the possibility of scaling dimensions to larger areas than achievable today. The goal of our Phase I program is to demonstrate growth of 1 cm2 area of single-crystal material in the base program and 2 cm2 in the Phase I Option, with a path in a Phase II program to grow 8 cm2 of single-crystal material. We will demonstrate in the Phase I program the following material characteristics: free hole density of at least 2 x 1013 cm-2; surface conducting channel Hall mobility of at least 200 cm2 V-1 s-1; bulk thermal conductivity of at least 1200 W cm-1 K-1; and a 4 Angstrom or better RMS roughness. The toroidal plasma reactor which we have developed offers a significant advantage over more conventional microwave plasma reactors in that it is readily scalable to even larger dimensions for future applications and is much more compact, energy efficient and gas-efficient.