Numerical Calculation of Excimer-Laser-Induced Lateral-Crystallization of Silicon Thin-Films

Excimer-laser-induced lateral-crystallization of Si thin-films has been characterized numerically. The effects of the Si film thickness, light intensity profile and thermal properties of the underlayer on grain growth are discussed. The tilted melt-solid interface is essential for large grain growth and the super-cooled Si region in front of the melt-solid is also important for quick start of crystal growth. It was concluded that the gradient method is suitable for large grain growth, since it can satisfy both requirements. Elongating the melt duration using a low specific heat underlayer can effectively delay the nucleation, resulting in ultra-large grain growth. The crystalline growth velocity is fastest at the Si-underlayer interface and thus preventing the heterogeneous nucleation at the interface by, such as, insertion of a low melting-point thin-film, is also effective for realizing large grain growth.