Gigabit-scale DRAM capacitor technology with high dielectric constant thin films by a novel conformal deposition technique

Author

Hayashi, S. ; Huffman, M. ; Azuma, M. ; Shimada, Y. ; Otsuki, T. ; Kano, G. ; McMillan, L.D. ; Paz de Araujo, C.A.

Author_Institution

Electron. Res. Lab., Matsushita Electron. Corp., Osaka, Japan

fYear

1994

fDate

7-9 June 1994

Firstpage

153

Lastpage

154

Abstract

High dielectric constant Ba/sub 0.7/Sr/sub 0.3/TiO/sub 3/ (BST) thin films with excellent thickness uniformity, within 5%, and adequate structural properties across an 8 inch wafer, are prepared by a novel aerosol-driven and photo-enhanced conformal deposition technique. Storage capacitors fabricated with an ultrathin BST film which has the lowest equivalent SiO/sub 2/ thickness of 0.37 nm reported thus far, show that leakage current density is 2/spl times/10/sup -8/ A/cm/sup 2/ under an applied voltage of 2 V and unit capacitance is 95 fFspl mu/m/sup 2/. Combining these material properties with the proposed conformal deposition technique which is applicable for stacked cell structures, is very promising as key technologies for the future gigabit-scale DRAMs.<>

Keywords

DRAM chips; barium compounds; capacitors; coating techniques; dielectric thin films; integrated circuit technology; leakage currents; metal-insulator-semiconductor devices; permittivity; strontium compounds; BST thin films; Ba/sub 0.7/Sr/sub 0.3/TiO/sub 3/; Ba/sub 0.7/Sr/sub 0.3/TiO/sub 3/ thin films; DRAM capacitor technology; aerosol-driven technique; conformal deposition technique; gigabit-scale DRAMs; high dielectric constant thin films; leakage current density; photo-enhanced technique; stacked cell structures; storage capacitors; thickness uniformity; ultrathin BST film; Binary search trees; Capacitance; Capacitors; Dielectric thin films; High-K gate dielectrics; Leakage current; Random access memory; Sputtering; Strontium; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

VLSI Technology, 1994. Digest of Technical Papers. 1994 Symposium on

Conference_Location

Honolulu, HI, USA

Print_ISBN

0-7803-1921-4

Type

conf

DOI

10.1109/VLSIT.1994.324411

Filename

324411