Substrates of fused silica or other refractory glasses are of interest for the fabrication of diamondbased electronic sensors (such as thermistors) and field-emitter arrays. For temperature-sensing applications, the diamond thin film layers must be deposited on thermally insulating substrates, in order to optimize the accuracy and dynamic response time of the device. Silica and silicate glasses are good insulators, providing a barrier to the heat flow out of the device and thereby allowing for optimized performance of temperature sensors. Also, fabrication of diamond field emitters on large area glass substrates is important for manufacture of field emission flat panel displays. Recently, it has been demonstrated that significant enhancement of diamond nucleation on Si02 substrates can be achieved by applying electrical bias to the substrate during its exposure to a microwave generated CH4/H2 plasma.

To investigate the nucleation mechanism of diamond on Si02 substrate, induced during the biasing pretreatment, several TEM techniques were used to characterize the films and the film/substrate interface.