United Microelectronics Assigned PatentFabricating silicon-oxide-nitride-oxide-silicon non-volatile memory cell
By Francis Pelletier on 2016.11.17
United Microelectronics Corporation, Hsinchu, Taiwan, has been assigned a patent (9,466,497) developed by Li, Kuo-Lung, Erlun Township, Taiwan, Shih, Ping-Chia, Tainan, Taiwan, Lee, Hsiang-Chen, Kaohsiung, Taiwan, Chang, Yu-Chun, Taichung, Taiwan, Wang, Chia-Wen, Tainan, Taiwan, Chen, Meng-Chun, Kaohsiung, Taiwan, and Hsu, Chih-Yang, Tainan, Taiwan, for a "method for fabricating a silicon-oxide-nitride-oxide-silicon, (SONOS) non-volatile memory cell."
The abstract of the patent published by the U.S. Patent and Trademark Office states: "The invention provides a method for fabricating a silicon-oxide-nitride-oxide-silicon, (SONOS) non-volatile memory cell, comprising: (S1) forming a pad oxide pattern on a silicon substrate having a recess exposing a tunnel region of the silicon substrate, (S2) forming a bottom oxide layer, a nitride layer, a top oxide layer covering the recess and the pad oxide pattern to form a first ONO structure, (S3) forming a photoresist on the first ONO structure covering the recess and a peripheral region of the pad oxide pattern, (S4) removing a part of the first ONO structure exposed by the photoresist to form an U-shaped ONO structure, (S5) trimming the photoresist to exposed a part of the U-shaped ONO structure above the recess, (S6) removing the part of the U-shaped ONO structure, (S7) removing the photoresist, (S8) removing the pad oxide pattern and the top oxide layer, and, (S9) forming a gate structure."
The patent application was filed on January 12, 2016 (14/993,102).