Heterogenous integration of diamond with non-native substrates

This thesis addresses the challenges with utilising diamond for integrated optical devices; a platform where its impressive material properties can be exploited. The major objective was to develop a process by which diamond could be heterogeneously integrated with non-native device platforms, to overcome its limited geometry. A process was developed for fabrication, handling, and hybrid integration of ultra thin diamond membranes. Plasma-etch chemistries were developed, that enabled such processing, and provided sub-nm r.m.s. roughness. Two sets of monolithic diamond structures were fabricated and transfer printed with a thickness down to ~10 nm. For thickness characterisation, diamond platelets, finding a low local-variation across typical device geometries. Diamond resonator devices were also fabricated and when integrated with SOI waveguides they showed high Q-factors as large as 1.8 x 10⁵. Thermo-optic tuning of these devices by > 450 pm at low mW powers was demonstrated, which has great significance to all integrated optical fields where resonant frequency of a cavity is important. The techniques developed are independent of integration platforms and are of wide reaching relevance to the optics community.