The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 15, 2009
Filed:
Sep. 21, 2004
Min-hwa Chi, Hsin-Chu, TW;
Wen-chuan Chiang, Hsin-chu, TW;
Cheng-ku Chen, Hsin-chu, TW;
Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu, TW;
Abstract
Disclosed herein is a DRAM memory cell featuring a reduced size, increased retention time, and compatibility with standard logic manufacturing processes, making it well-suited for use as embedded DRAM. The memory cell disclosed herein includes a pass-gate transistor and a storage region. The transistor includes a gate and a drain. The storage region includes a trench, which is preferably a Shallow Trench Isolation (STI). A non-insulating structure, e.g., formed of polysilicon or metal, is located in the trench as serves as a capacitor node. The trench is partially defined by a doped sidewall that serves as a source for the transistor. The poly structure and the trench sidewall are separated by a dielectric layer. The write operation involves charge transport to the non-insulating structure by direct tunneling through the dielectric layer. The read operation is assisted by Gate Induced Drain Leakage (GIDL) current generated on the surface of the sidewall.