AVS 52nd International Symposium
    Electronic Materials and Processing Tuesday Sessions
       Session EM-TuP

Paper EM-TuP5
Structural and Electrical Properties of PZT Thin Films Patterned by Chemical Mechanical Polishing Process for FRAM Applications

Tuesday, November 1, 2005, 4:00 pm, Room Exhibit Hall C&D

Session: Electronic Materials and Processing Poster Session
Presenter: N.-H. Kim, Chosun University, Korea
Authors: N.-H. Kim, Chosun University, Korea
P.-J. Ko, Chosun University, Korea
G.-W. Choi, Chosun University, Korea
Y.-J. Seo, Daebul University, Korea
W.-S. Lee, Chosun University, Korea
Correspondent: Click to Email
Ferroelectric random access memory (FRAM) has been considered as one of future memory devices due to its ideal memory properties such as non-volatility, high charge storage, and faster switching for the readywrite operations. The lead zirconate titanate (PZT) is one of the most attractive perovskite-type materials for realizing the ferroelectric products due to its higher remanant polarization and the ability to withstand higher coercive fields. The sol-gel solution of Pb@sub 1.1@(Zr@sub 0.52@Ti@sub 0.48@)O@sub 3@ was spin-coated on patterned substrate. The thin films were polished by chemical mechanical polishing (CMP) technique. The vertical sidewall of the PZT pattern was successfully achieved, because the patterning of the PZT thin films was performed by using a damascene process. In this study, the surface morphology and the electrical properties of PZT capacitors were evaluated after CMP process. The selectivities for end-point detection to top electrode materials and TEOS film were also studied. Surface morphology after CMP process was undergone with atomic force microscopy (AFM) of PSIA Company. The electrical properties were measured between the top and bottom electrodes. Capacitance and leakage current of PZT capacitors after CMP are examined. The capacitance was measured by using an HP 4192 impedance/gain-phase analyzer at 10 kHz, and the leakage current density was determined by using an HP 4145B semiconductor parameter analyzer. The crystal structure of the polished samples was investigated by X-ray diffraction (XRD) to observe the variation of phases. The improved PZT capacitor with the high capacitance and the low leakage current could be obtained by analyzing correlation between electrical properties and various CMP process parameters. Acknowledgement: This work was supported by a Korea Research Foundation grant (KRF-2004-005-D00007).