Title :
Ultra-thin fatigue free lead zirconate titanate thin films for gigabit DRAMs
Author :
Torii, K. ; Kawakami, H. ; Kushida, K. ; Yano, F. ; Ohji, Y.
Author_Institution :
Central Res. Lab., Hitachi Ltd., Kokubunji, Japan
Abstract :
Thin films of Pb-based ferroelectric materials have attracted much attention because of the potential use as the dielectric in the storage capacitors of 1 Gb DRAMs. Sputtering, sol-gel, pulsed laser deposition, and metal organic chemical vapor deposition are widely used for ferroelectric film preparation; but there have been few reports using vacuum evaporation. This may be because lead has a low affinity for oxygen and high volatility. We can overcome these problems by employing high-concentration ozone. The thickness scaling of ferroelectric lead zirconate titanate (PZT) thin films by reactive evaporation is investigated.
Keywords :
DRAM chips; capacitors; ferroelectric capacitors; ferroelectric thin films; lead compounds; piezoceramics; vacuum deposition; 1 Gbit; PZT; PZT thin films; PbZrO3TiO3; dielectric thin films; ferroelectric materials; gigabit DRAMs; high-concentration ozone; reactive evaporation; storage capacitors; thickness scaling; vacuum evaporation; Dielectric thin films; Environmentally friendly manufacturing techniques; Fatigue; Ferroelectric materials; Lead; Material storage; Pulsed laser deposition; Sputtering; Titanium compounds; Transistors;
Conference_Titel :
VLSI Technology, 1995. Digest of Technical Papers. 1995 Symposium on
Conference_Location :
Kyoto, Japan
Print_ISBN :
0-7803-2602-4
DOI :
10.1109/VLSIT.1995.520889
