Patent ID: 8187936

Claim:
A method of making a monolithic three dimensional NAND string, comprising: forming a stack of alternating layers of a first material and a second material over a substrate, wherein the first material comprises a conductive or semiconductor control gate material and wherein the second material comprises an insulating material; etching the stack to form at least one opening in the stack; selectively etching the first material to form first recesses in the first material; forming a blocking dielectric in the first recesses; forming a plurality of discrete charge storage segments separated from each other in the first recesses over the blocking dielectric; forming a tunnel dielectric over a side wall of the discrete charge storage segments exposed in the at least one opening; and forming a semiconductor channel in the at least one opening; wherein the step of forming a semiconductor channel in the at least one opening comprises: forming an amorphous semiconductor layer in the at least one opening and over the stack of the alternating layers; forming a nucleation promoter layer over the amorphous semiconductor layer; recrystallizing the amorphous semiconductor to form polycrystalline semiconductor layer; and removing the nucleation promoter layer and an upper portion of the polycrystalline semiconductor layer using top surface of the stack of alternating layers as a stop.