Patent ID: 6383899
Filing Date: 2002-05-07
Classification: H01L

Abstract:
A solid-phase crystallization process of forming a TFT semiconductor film of polycrystalline semiconductor matter from a film containing the matter in an amorphous state, comprising:choosing silicon as the amorphous matter; depositing on a substrate by plasma-enhanced chemical vapor deposition a single film of substantially amorphous matter so that there is an interface between the film and the substrate; modulating formation of crystals in the amorphous matter, wherein the modulating includes the substeps of first partially crystallizing the amorphous matter to form in the film at the interface regions of microcrystallite matter particles adjacent regions of noncrystallized matter, and, subsequent to partially crystallizing implanting in the film ions of a preselected type, and at a preselected energy, dose and species to selectively eliminate a fraction of the microcrystallite matter particles, and further to amorphize the non-crystallized regions, wherein the partially crystallizing step includes a substep of inducing to cause formation of microcrystallite silicon particles by heating the film, and wherein the implanting is performed using a dose for silicon of <1Ã—1016 cm âˆ’2 at an energy of less than about 100 keV, and by using a dose for germanium of &lE;1Ã—1015 cmâˆ’2 at an energy of less than about 22 keV; controlling process temperature to be &lE;600Â° C.; and subsequent to the implanting, annealing of the film to at least substantially form modulated polycrystalline matter usable as a TFT semiconductor film of polycrystalline semiconductor matter.