Transistor with sonos structure having barrier wall over adjacent portions of the select transistor well and memory transistor well

Abstract

The present disclosure provides a manufacturing method for a transistor with an SONOS structure, including providing a semiconductor substrate, wherein the semiconductor substrate includes a select transistor well and a memory transistor well; depositing an oxide layer on an upper surface of the select transistor well, depositing an ONO memory layer on an upper surface of the memory transistor well, depositing a barrier wall over adjacent portions of the select transistor well and the memory transistor well, depositing polycrystalline silicon covering the oxide layer, the ONO memory layer, and the barrier wall, and etching the polycrystalline silicon, to retain the polycrystalline silicon deposited on both sides of the barrier wall so as to form a select gate and a memory gate, and removing the oxide layer and the ONO layer on a surface of the semiconductor substrate other than the select gate, the barrier wall, and the memory gate.

Dependencies are inferred from the claim text.