In the manufacturing of a 32M ferroelectric random access memory (FRAM) device on the basis of 0.25 design rule (D/R), one of the most difficult processes is to pattern a submicron capacitor module while retaining good ferroelectric properties. In this paper, we report the ferroelectric property of patterned submicron capacitor modules with a stack height of 380 nm, where the 100 nm-thick Pb(Zr, Ti)O 3 (PZT) films were prepared by the sol-gel method. After patterning, overall sidewall slope was approximately 70 • and cell-to-cell node separation was made to be 80 nm to prevent possible twin-bit failure in the device. Finally, several heat treatment conditions were investigated to retain the ferroelectric property of the patterned capacitor. It was found that rapid thermal processing (RTP) treatment yields better properties than conventional furnace annealing. This result is directly related to the near-surface chemistry of the PZT films, as confirmed by X-ray photoelectron spectroscopy (XPS) analysis. The resultant switching polarization value of the submicron capacitor was approximately 30 µC/cm 2 measured at 3 V.

Bi4.xLaxTi3012 ceramics with various La contents (x=O, 0.25, 0.50, 0.75, 1-00) are fabricated using ordinary firing (OF) and hot forging (HF) method. The hysteresis loop of BLT film deposited with HF[//I ceramic target displays low remnant polarization compared with that of OF ceramic target. The grain orientation of the ceramic target has a remarkable influence on the hysteresis loop of the film grown using PLD method. So, it is necessary to use the HF[I] ceramic target in the PLD process in order to obtain good ferroelectric properties for the film. Kewords:Bi3.75La075Ti3012, pulsed laser deposition, hot-forging, ferroelectric thin film, grain orientation Downloaded by [La Trobe University] at 22:13 15 June 2016 I20/[464] ILL WON KIM e t a [