Access Transistor of a Nonvolatile Memory Device and Method for Fabricating Same

摘要

A three-dimensional integrated circuit nonvolatile memory array includes a memory array of vertical channel NAND flash strings connected between an upper layer connection bit line and a substrate which includes one or more elevated source regions disposed on at least one side of each row of NAND flash strings so that each NAND flash string includes a lower select transistor with a first channel portion that runs perpendicular to the surface of the substrate through a vertical channel string body, a second channel portion that runs parallel to the surface of the substrate, and a third channel portion that runs perpendicular to the surface of the substrate through the elevated source region.

主权项

1. A nonvolatile memory device, comprising:
a nonvolatile memory array comprising a plurality of memory cell pillars extending from a substrate with an access transistor located at the bottom of each memory cell pillar, the access transistor comprising:
a drain in said memory cell pillar,a vertical channel body portion of said memory cell pillar connected between the drain and the substrate,an elevated source region protruding from a top surface of the substrate and being adjacent to the vertical channel body portion,a horizontal channel body portion formed in the substrate between the vertical channel body portion and the elevated source region, anda lower select line gate electrode formed around the bottom of said memory cell pillar to be insulated from and at least partially positioned between the vertical channel body and the elevated source region for said memory cell pillar.