AVS 53rd International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS1-TuP

Paper PS1-TuP2
Damage Recovery of (Bi@sub4-x@La@subx@)Ti@sub3@O@sub12@ Thin Films during the Etch Process using Inductively Coupled Plasma Sources

Tuesday, November 14, 2006, 6:00 pm, Room 3rd Floor Lobby

Session: Etching of High-K, Compound Semiconductors and Advanced Materials Poster Session
Presenter: J.G. Kim, Chung-Ang University, Korea
Authors: J.G. Kim, Chung-Ang University, Korea
G.H. Kim, Chung-Ang University, Korea
K.T. Kim, Chung-Ang University, Korea
C.I. Kim, Chung-Ang University, Korea
Correspondent: Click to Email
Ferroelectric thin films are employed for ferroelectric random access memories (FeRAMs). FeRAMs offer non-volatility, a lower voltage operation and larger write cycle numbers. (Bi@sub4-x@La@subx@)Ti@sub3@O@sub12@ (BLT) thin films were proposed as a promising ferroelectric material that does not exhibit the polarization fatigue, does have bigger remanent polarization value than that of SrBi@sub2@Ta@sub2@O@sub9@. Moreover, it does not contain the lead contents which occurs environmental disruption. Accordingly, for high density FeRAMs, the etching mechanism of BLT thin films and surface damage during the etching process must be understood. Moreover, damaged films during the etch process should be improved. However, although the etching mechanism was already examined in several researchers, etch damages of BLT thin films and its recovery was not established. In this work, the etch damages of BLT thin films in inductively coupled plasma were investigated with various gas mixing ratios, ICP powers, and bias powers. The etch rates were measured using a surface profiler. For investigating the effects of O@sub2@ plasma, O@sub2@ addition was performed during the etching and etched samples which did not add O@sub2@ gas were treated in the O@sub2@ plasma. After the etching process, the leakage current was measured by parameter analyzer. To evaluate plasma induced physical damages, the changes of lattice of etched BLT samples were evaluated with x-ray diffraction. The precision workstation ferroelectric test apparatus was used for measurement of P-E hysteresis curves. Also the etched surface roughness was evaluated by atomic force microscopy and scanning electron microscope.