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:
Jan. 18, 2005
Filed:
Mar. 05, 2003
Toshiaki Kirihata, Poughkeepsie, NY (US);
John W. Golz, Manassas, VA (US);
Toshiaki Kirihata, Poughkeepsie, NY (US);
John W. Golz, Manassas, VA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A two-port dynamic random access memory (DRAM) cell consisting of two transistors and two trench capacitors (2T and 2C DRAM cell) connecting two one transistor and one capacitor DRAM cell (1T DRAM cell) is described. The mask data and cross-section of the 2T 2C DRAM and 1T DRAM cells are fully compatible to each other except for the diffusion connection that couples two storage nodes of the two 1T DRAM cells. This allows a one-port memory cell with 1T and 1C DRAM cell and a two-port memory cell with 2T and 2C DRAM cell to be fully integrated, forming a true system-on chip architecture. Alternatively, by halving the capacitor, the random access write cycle time is further reduced, while still maintaining the data retention time. The deep trench process time is also reduced by reducing by one-half the trench depth.