Korean Journal of Chemical Engineering, Vol.15, No.1, 85-89, January, 1998
THE INFLUENCE OF CHEMICAL PASSIVATION ON THE PZT/Pt ELECTRODE INTERFACE
It has been recognized that the interdiffusion of atomic species between a PZT film and the Pt bottom electrode leads to the gradual degradation of a PZT capacitor. In order to prevent this interdiffusion, experimental studies on chemical passivation to the bottom electrode surface were carried out by the sulfurization method. It was observed that a sulfur layer was built up on the Pt substrate with small grains, which resulted in a structural change at the Pt surface. Atomic force microscopy (AFM) showed that the film roughness of the Pt surface was increased by sulfur treatment. Pb(Zr0.5Ti0.5)O3(PZT) thin films were prepared on a Pt/Ti/SiO2/Si bottom electrode by spin-coating techniques. The microstructure and the preferred orientation of the PZT films were shown to depend on the sulfurtreated electrode. The PZT capacitor on a clean Pt electrode was confirmed to be ferroelectric with Pr=17.7 μC/㎠ and Ec=65 kV/cm from the P-E hysteresis curves. The fatigue behavior of a PZT film capacitor prepared on a sulfurtreated one was observed to be relaxed, but the absolute value of Pr was paid off.
- Chung CW, Kim D, Korean J. Chem. Eng., 14(2), 136 (1997)
- Desu SB, Yoo IK, "Ferroelectric PbZrxTi1-xO3 Thin Films Grown by Organometallic Chemical Vapor Depositon," Proc. 4th Int. Symp. Integrated Ferroelectrics, Monterey, 640 (1990)
- Dormans GJM, Keijer M, Veldhaven PJ, "Ferroelectric PbZrxTi1-xO3 Thin Films Growns by Organometallic Chemical Vapor Deposition," Proc. Symp. Mat. Res. Soc., 203 (1992)
- Maeda F, Watanabe Y, Oshima M, Appl. Phys. Lett., 62(3), 297 (1993)
- Makamura T, Nakao Y, Kamisawa A, Takasu H, Jpn. J. Appl. Phys., 33, 5207 (1994)
- Mihara T, Watanabe H, Carlos AP, Jpn. J. Appl. Phys., 33, 3996 (1994)
- Nannichi Y, Oigawa H, "The Effects of Sulfur on the Surface of III-IV Component Semiconductors," Extended Abstracts of 22nd Int. Conf. on Solid State Devices and Materials, Sendai, 453 (1990)
- Ohno H, Kamanishi H, Akagi Y, Nakajima Y, Hijikata T, Jpn. J. Appl. Phys., 29(11), 2473 (1990)
- Oigawa H, Fan J, Nannichi Y, Sugahawa H, Oshima M, Jpn. J. Appl. Phys., 30, L322 (1991)
- Scott JF, Melnick BM, Araujo CA, McMillan LD, Zuleeg R, "d.c. Leakage Currents in Ferroelectric Memories," Integrated Ferroelectrics, 1, 323 (1992)
- Spierings GACM, Ulenaers MJE, Kampschoer GLM, van Hal HAM, Larsen PK, J. Appl. Phys., 70(4), 2290 (1991)