Diamond Based Silicon-on-Insulator Materials and Devices

Abstract

Silicon-on-insulator materials with buried diamond films were manufactured by a wafer bonding and etch-back procedure. These advanced silicon-on-insulator structures were made to address self-heating effects observed in conventional silicon-on-insulator materials with buried silicon dioxide layers. The compatibility of polycrystalline diamond films to silicon device manufacturing was evaluated by process experiments combined with Raman spectroscopy. A method of encapsulating the diamond film during oxidation procedures in device manufacturing was developed. Resistors, diodes and MOS-transistors were made in the silicon film and were used to characterise the diamond based silicon-on-insulator material. The results show a better heat dissipation capability of the material as compared to conventional silicon-on-insulator materials. Well-working diodes and MOS-transistors were made in the active silicon film. It can be concluded that no fundamental obstacles exist for forming these materials and for transferring a silicon device process onto the material. The main problem during the project came from stress and surface roughness of the diamond films. In the future, when a more mature diamond deposition technology is available, it should be possible to overcome these problems.