Method for manufacturing metal oxide semiconductor transistor of e.g. flash memory of contact smart card, involves oxidizing vacuum zone to form enlarged zone of insulating layer between floating gate and substrate on source area side

摘要

The method involves forming a source area (22) and a drain area (23) in a substrate (21). A floating gate (32) accumulating electric charges is separated from the substrate by an insulating layer (25). A part of the insulating layer located on a side of the source area is deoxidized to form a vacuum zone by performing buffered oxide etching (BOE) using a mask. The vacuum zone is oxidized to form an enlarged zone of the insulating layer between the floating gate and the substrate on the side of the source area. Independent claims are also included for the following: (1) a method for manufacturing an electrically programmable memory (2) a transistor (3) an electrically programmable non-volatile memory (4) an electronic system.