on a single insulating film or alternatively interposed between a plurality of insulating films conversely the insulating film may be disposed on a single semiconducting or metallic film or alternatively interposed between multiple semiconducting or metallic films or both the most rapid mechanism for crystallization of thin amorphous layers is solid phase epitaxial re growth sper in sper amorphous si may transform to crystalline si by extending an underlying pre existing extensive crystal layer this scenario is commonly encountered during annealing of a surface layer of a crystalline si wafer after it has been amorphized by ion implantation the present disclosure relate to processing an amorphous substrate in which an extensive pre existing lattice does not exist and which phase transformation occur via crystal nucleation prior to the growth of the crystals referring to fig1 there is shown a block diagram of various mechanisms through which a material without extensive pre existing lattice may transform from an amorphous phase into a crystalline phase as known in the art the crystalline phase may be categorized as a poly crystalline phase or a mono crystalline phase the poly crystalline phase may sometimes be further subdivided into different categories such as multi micro nano crystalline etc depending on the crystal size however such a distinction may not be important in the context of this disclosure and may not be necessary to describe fig1 accordingly these phases may be referred herein collectively as.