Thermal Conductivity of Diamond-Based Silicon-on-Insulator Structures

Diamond films of various thickness (1-300μm) were deposited on single-crystal Si active (300 μm) by a microwave plasma chemical vapor deposition method using gaseous mixtures of methane and hydrogen. After thinning of the Si layer by machine and ion-beam polishing a diamond-based silicon-on-insulator structure with final Si layer thickness of about 1μm is formed. Thermal conductivity of this structure material with various thicknesses of diamond and Si layer was measured. Compared with bulk silicon, the thermal conductivity of the siliconon-diamond structure with 300μm diamond and 1μm silicon increases by 850%.