Single-crystalline Si on insulator in confined structures fabricated by two-step metal-induced crystallization of amorphous Si

We present a technology and its mechanism to obtain single-crystalline Si pillars on SiO2 using a two-step Ni-induced crystallization process on amorphous Si pillars with confined sizes. The amorphous Si pillars with a Ni cap were first annealed at 400 degreesC for 15 h so that a single-crystalline NiSi2 template was formed on top of each pillar. In the second step, they were annealed at 550 degreesC for 2 h, during which single-crystalline Si pillars were formed by NiSi2-mediated solid-phase epitaxy. These single-crystalline Si pillars can be used for advanced vertical metal-oxide-semiconductor transistors and surround-gate structures, especially where low-temperature processing is required. (C) 2002 American Institute of Physics.