Low-temperature crystallization of amorphous silicon films in contact with palladium by hydrogen plasma heating

Abstract

A new annealing process using hydrogen plasma heating was suggested for the fabrication of poly-Si (polycrystalline silicon) films. This fabrication process had the advantages of low processing temperature approximately 450 degreesC and a short processing time of 1 h. The a-Si (amorphous silicon) films and a-Si/Pd (palladium) bilayers were deposited by r.f. sputtering and subsequently annealed by conventional furnace heating and hydrogen plasma heating. It was found that the Pd layer, introduced to the surface of the glass substrate prior to deposition of the a-Si layer. enhanced the nucleation reaction of c-Si (crystalline silicon) during the annealing, and that hydrogen plasma heating enhanced the grain growth reaction effectively. These resulted in lowered processing temperature and reduced processing time, while the grain size in the poly-Si films annealed by hydrogen plasma heating was much larger than that in the films by conventional furnace heating. The grain size of the poly-Si films annealed by hydrogen plasma heating was approximately 0.3 mum. (C) 2002 Elsevier Science B.V. All rights reserved.