Comparative study of textured diamond films by thermal conductivity measurements

Superior thermal conductivity, high resistance, high breakdown voltage and wide band gap make diamond an attractive material for a variety of applications in electronics. One of its most appealing applications is as a buried dielectric in silicon-on-diamond (SOD) technology. This paper presents thermal conductivity measurements conducted on a series of diamond films (grown by the microwave plasma chemical vapor deposition technique) as a function of the sample morphology and thickness, for eventual incorporation in the SOD structures. Results show that there is a significant difference in the measured thermal conductivity between samples with fiber texture and samples with sheet texture. Also, measurements performed on a 160-μm-thick diamond sample before and after reactive ion etching of approximately 10 μm of the nucleation layer show no significant change in the measured value of the thermal conductivity. PACS 81.05.Uw; 65.40.-b; 61.72.-y