Patent attributes
Nonvolatile memory devices include an electrically insulating layer on a semiconductor substrate and a NAND-type string of nonvolatile memory cells on an upper surface of the electrically insulating layer. The NAND-type string of nonvolatile memory cells includes a plurality of vertically-stacked nonvolatile memory cell sub-strings disposed at side-by-side locations on the electrically insulating layer. A string selection transistor is provided, which includes a gate electrode extending between the electrically insulating layer and the semiconductor substrate and source and drain regions in the semiconductor substrate. A ground selection transistor is provided, which includes a gate electrode extending between the electrically insulating layer and the semiconductor substrate and source and drain regions in the semiconductor substrate.