Quantum-well memory device and method for making the same

摘要

A quantum-well memory device and method is provided. The quantum-well memory device includes a substrate with two junctions. A sandwiched gate insulator is formed on top of the substrate and extended in length between the two junctions. The sandwiched gate insulator has a top layer, a middle layer, and a bottom layer. The middle layer is more soluble to an acid etch than the top and the bottom layer of the gate insulator. Polysilicon inserts are defined at the undercuts formed by selectively and self-limitedly etching the sidewalls of the middle layer of the gate insulator. The polysilicon inserts are positioned beside the middle layer and between the top layer and the bottom layer of the gate insulator. A method for fabricating such a device is also described.