Integrated circuit device including polycrystalline semiconductor film and method of manufacturing the same

An integrated circuit (IC) device comprising:

• a peripheral circuit formed at a first vertical level on a substrate;
• a polycrystalline silicon film formed on the peripheral circuit at a second vertical level above the first vertical level;
• and
• a memory cell array formed on the polycrystalline silicon film at a third vertical level above the second vertical level, wherein the memory cell array vertically overlaps the peripheral circuit;
• wherein the polycrystalline silicon film comprises a plurality a flat horizontal portion, which provides an active region of the plurality of memory cell strings, and a plurality of vertically protruding portions protruding from the flat portion toward the peripheral circuit.

An integrated circuit (IC) device comprising:

• a first level semiconductor circuit formed on a substrate at a first vertical level;
• a second level semiconductor circuit formed on the first level semiconductor at a second vertical level;
• and
• a polycrystalline semiconductor thin film interposed between the first level semiconductor circuit and the second level semiconductor circuit;
• wherein the polycrystalline semiconductor thin film comprises at least one semiconductor single crystal, and the at least one semiconductor single crystal comprises a flat horizontal portion, which provides an active region of the second level semiconductor circuit, and a pin-shaped protruding portion protruding from the flat horizontal portion toward the first level semiconductor device.