Study of diamond film interface structure and contacting area

Abstract

High purity diamond film has been grown by refined Combustion Flame method with high oxygen proportion. Snapshots of time series of the diamond film forming were taken and a model was derived. By observing the period of seeding to coalescing of diamond crystals to form film, it is realized that the contacting area is small and the calculated value was less than 15%. It is also found that the base layer of the film was porous as a result of non-uniform crystal growth. To enhance adhesion of the film, the contacting area between the film and the substrate must be increased, and the porous base layer must be thin and dense as much as possible. To achieve that, very high and uniform nucleation is the key. Under this view, the nanocrystalline diamond film on smooth substrate is preferred than rough surface to have strong adhesion.

Effect of Nanocrystalline Diamond Films Deflection on Wear Observed in Reciprocating Sliding Tests

“…The dislocations network and hot-spots were discussed in Introduction. Following the publications by Williams et al [30], Williams [31] and Setasuwon and Metanawin [32], a structure at the interface between the diamond film and the Si substrate is schematically shown in Figure 5. The properties of the diamond film structure formed during the early stage of the film growth can differ from those of the core part of diamond film.…”

Comparative Analysis of Two Methods for Evaluating Wear Rate of Nanocrystalline Diamond Films

“…The NCD structure consists of seeding particles, diamond grains and ballas-like nano-diamond material between the grains (Fig. 4a) [9][10][11]. Assuming Hertz contact between the ball and the film, the maximum contact pressure is 2.4 GPa.…”