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:
Aug. 24, 1999
Filed:
Jun. 23, 1997
Cheng-Yeh Shih, Hsin-Chu, TW;
Yuan-Chang Huang, Hsin-Chu, TW;
Chue-San Yoo, Pao-San Hsiang, TW;
Wen-Chan Lin, Hsin-Chu, TW;
Taiwan Semiconductor Manufacturing Company, Ltd, Hsin-Chu, TW;
Abstract
A method for making improved capacitor bottom electrodes (capacitor nodes) having longer refresh cycle times and increased capacitance for DRAM cells has been achieved. The method involves using a polysilicon high-temperature film (HTF) instead of the conventional doped polysilicon to form the node capacitors. After forming the DRAM pass transistors (FETs) and depositing an insulating layer, node contact openings are etched in the insulator to the drain of the FET. The capacitor bottom electrodes are formed by depositing a polysilicon HTF at a temperature of at least 650.degree. C. using a reactant gas mixture of H.sub.2 /SiH.sub.4 /PH.sub.3, which results in a longer refresh cycle time and increased capacitance. This results in a significantly improved final die yield. After forming an interelectrode dielectric layer on the bottom electrodes, another doped polysilicon layer is deposited to form the top electrodes to complete the DRAM cells.