LAyer Selection by ERase (LASER) With an Etch-Through-Spacer Technique in a Bit-Line Stacked 3-D nand Flash Memory Array

A novel electrical layer-selection method in a bit-line stacked 3-D nand memory array is proposed. The stacked layers are selected by using multiple source select lines with erased cells in a layer. The operation scheme and simulation results for the electrical layer selection are discussed. An etch-through-spacer technique is developed to form a terraced body for a vertical contact process.