THREE-DIMENSIONAL SEMICONDUCTOR MEMORY DEVICE

A semiconductor device includes a first bit line extending in a first direction, a first semiconductor pattern extending in a second direction and including first and second ends opposite to each other, the first end of the first semiconductor pattern being in contact with the first bit line, a first word line on the first semiconductor pattern and extending in a third direction, a selection line adjacent to the second end of the first semiconductor pattern and parallel to the third direction, a second semiconductor pattern interposed between the selection line and the first semiconductor pattern and having first end and second ends opposite to each other, a second bit line extending in the first direction and in contact with the first end of the second semiconductor pattern, and a source line extending in the first direction and in contact with the second end of the second semiconductor pattern.