Method for forming a flash memory cell having contoured floating gate surface

摘要

Methods are provided for forming a contoured floating gate for use in a floating gate memory cell. One method includes forming a floating gate that has a polysilicon layer over a substrate; forming oxide layers on opposing sides of the floating gate, the oxide layer having a vertical thickness greater than a vertical thickness of the floating gate; forming a spacer layer over the oxide layers and the floating gate; removing a portion of the spacer layer such that a top surface of the floating gate positioned laterally toward a middle region of the floating gate is exposed; and removing a portion of the floating gate underlying the exposed top surface of the middle region to form the contoured floating gate.