AVS 53rd International Symposium
    Thin Film Thursday Sessions
       Session TF-ThP

Paper TF-ThP8
Leakage Current and Dielectric Loss of BLT Thin Film Capacitors Fabricated by Chemical Mechanical Polishing (CMP) with Changes of Polishing Pressure

Thursday, November 16, 2006, 5:30 pm, Room 3rd Floor Lobby

Session: Thin Film Poster Session
Presenter: P.-G. Jung, Chosun University, Korea
Authors: P.-G. Jung, Chosun University, Korea
N.H. Kim, Chosun University, Korea
W.-S. Lee, Chosun University, Korea
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PZT thin films, which are the representative ferroelectric materials in ferroelectric random access memory (FRAM), have some serious problem such as the imprint, retention and fatigue which ferroelectric properties are degraded by repetitive polarization. BLT thin films have many advantages such as highly fatigue resistant characteristic, low processing temperature, and large remanent polarization. BLT thin film capacitors were fabricated by plasma etching, however, the plasma etching of BLT thin film was known to be very difficult. In our previous study, the ferroelectric materials such as PZT and BLT were patterned by chemical mechanical polishing (CMP) using damascene process to top electrode/ferroelectric material/bottom electrode. It is also possible to pattern the BLT thin film capacitors by CMP, however, the CMP damage was not considered in the experiments. The properties of BLT thin films were changed by the change of polishing pressure although the removal rate was directly proportional to the polishing pressure in CMP process. The structural property of BLT thin films after CMP with the change of the polishing pressure and then the behaviors of leakage current and dielectric loss were compared with the structural property. In view of the results so far achieved, the removal rate and the leakage current must be considered simultaneously when the polishing pressure of CMP process parameter were decided. Acknowledgement: This work was supported by Korea Research Foundation Grant (KRF-2004-005-D00007).