SIMOX material: from research to production

A 150 m/sup 2/ class 100 clean room, specially dedicated for separation by implantation of oxygen (SIMOX) wafer production on a semi-industrial basis, has been set up at LETI. This facility includes a very high current oxygen ion implantation machine (Eaton NV-200), a high temperature annealing furnace (temperature up to 1350 degrees C, six inches capability), and nondestructive characterization tools. The characterization techniques include IR absorption, nuclear reaction analysis, and spectral reflectivity analysis that allows automatic measurement of silicon thickness down to 100 nm. Contamination levels are routinely checked by SIMS (secondary ion mass spectrometry) and the structure and crystalline quality are monitored using TEM and XTEM analysis. Different methods for producing thin silicon film SIMOX wafers-sacrificial oxidation, implantation through oxide, and reduction of the implantation energy-are briefly outlined.<
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