The experimental mapping of the independent input variables into the output diamond thin film properties

Summary form only given. The many different experimental variables associated with a CVD diamond film reactor can be divided into three groups: (1) independently controllable input variables U(u/sub 1/,u/sub 2/,u/sub 3/,...u/sub p/), (2) dependent internal variables X(x/sub 1/, X/sub 2/, X/sub 3/,...X/sub n/) and (3) output film characteristics Y(y/sub 1/, y/sub 2/, y/sub 3/,...Y/sub k/) where in general X=f(U) and Y=g(U,X). For example, power, pressure, total flow rate, gas composition, deposition time, and reactor type and geometry could be considered as independently controllable input variables while substrate temperature, hydrogen translational temperature, discharge volume and area, species flux and concentrations, gas residence time, and discharge absorbed power densities may be considered as dependent internal variables. Finally, film morphology, growth rate, yield, carbon conversion efficiency uniformity, film quality, texture, and electrical properties could be considered as output characteristics associated with CVD diamond films for a reactor. Despite the considerable experimental data published over the past ten years concerning diamond thin film deposition, the relationship between film morphology and the many experimental variables is still not well understood. This paper attempts to understand the relationship between various output characteristics and various input/internal variables of microwave plasma-assisted diamond deposition reactors.