Formation of location-controlled crystalline islands using substrate-embedded seeds in excimer-laser crystallization of silicon films

Abstract

Single-crystal thin-film transistors on nonrefractory materials such as glass can be realized if monocrystalline islands of sufficient sizes can be grown at a predetermined position. By artificially controlling the super-lateral growth phenomenon observed in excimer-laser crystallization, this could be achieved. In this letter, we present such a method in which the silicon filling of a very small indentation fabricated in the substrate will act as a seed for lateral growth of large grains. When the melt is deep in these indentations, lateral growth is preceded by a vertical growth phase during which grains become occluded, so that a high yield of monocrystalline islands is obtained.