ABSTRACT
For the sake of fabricating the ultrahigh density ultralarge scale integration (ULSI) memory chips, the ferroelectric nanostructures growth through self-assembly are studied. In this paper, we synthesize the lanthanum and niobium substituted Bi4Ti3O12 nanostructures on Pt/Ti/SiO2/Si substrates. The method we used here was spin coating precursors with a serious of concentration on the substrates and then annealing at 700°C or 750°C in the oxygen atmosphere to get the self-patterning nano particles. Scanning probe microscope (SPM), and x-ray diffraction (XRD) were used to detect the morphology and the crystalline structure of the nano particles. The well-separated Bi3.15Nd0.85Ti3O12 particles have a typical lateral size about 100–150 nm and height about 20–25 nm. XRD reveals pyrochlore phase in the low concentration samples. The lower the precursor's concentration is, the higher the excess of Bi element is needed to form the pure perovskite nanoparticles.
Acknowledgment
This work was supported by the National Science Foundation of China (No 90207027, 90401014), the 973 Project of MOST (2002CB613303) of China, and Jiangsu Natural Science Foundation (No. BK 2002410, BK2004084).