Al-induced lateral crystallization of amorphous Si thin films by microwave annealing

Abstract

Al-induced lateral crystallization of amorphous silicon thin films by microwave annealing is investigated. The crystallized Si films are examined by optical microscopy, Raman spectroscopy, transmission electron microscopy and transmission electron diffraction micrography. After microwave annealing at 480 °C for 50 min, the amorphous Si is completely crystallized with large grains of main (111) orientation. The rate of lateral crystallization is 0.04 μm/min. This process, labeled MILC-MA, not only lowers the temperature but also reduces the time of crystallization. The crystallization mechanism during microwave annealing and the electrical properties of polycrystalline Si thin films are analyzed. This MILC-MA process has potential applications in large area electronics.

Keywords

semiconductor / thin film / crystal growth / phase transition

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