Laser crystallisation of poly-SiGe for microbolometers

Bolometers based on micromachined poly-SiGe as active elements have recently been demonstrated. The advantage of using poly-SiGe relies on its low thermal conductivity, high coefficient of temperature resistance and perfect compatibility with the IC silicon technology. In order to simplify a device integration of such elements, a combination of laser-assisted low thermal budget techniques such as laser-induced chemical vapour deposition and laser-assisted crystallisation has been proposed. The present paper shows the first results obtained using this “all laser-assisted” process for producing amorphous as well as polycrystalline SiGe alloys and the simulation of the crystallisation processes via numerical analysis for tuning the parameters of the crystallisation process.