ZERO SHRINKAGE SMOOTH INTERFACE OXY-NITRIDE AND OXY-AMORPHOUS-SILICON STACKS FOR 3D MEMORY VERTICAL GATE APPLICATION

Methods are provided for depositing a stack of film layers for use in vertical gates for 3D memory devices, by depositing a sacrificial nitride film layer at a sacrificial film deposition temperature greater than about 550° C.; depositing an oxide film layer over the nitride film layer, at an oxide deposition temperature of about 600° C. or greater; repeating the above steps to deposit a film stack having alternating layers of the sacrificial films and the oxide films; forming a plurality of holes in the film stack; and depositing polysilicon in the plurality of holes in the film stack at a polysilicon process temperature of about 700° C. or greater, wherein the sacrificial film layers and the oxide film layers experience near zero shrinkage during the polysilicon deposition. Flash drive memory devices may also be made by these methods.