Bi-system Layered Ferroelectric Thin Films Bto And Sbto, Structure And Performance

In the 90's of 20 century, with the quick development of microelectronics and computer industry, ferroelectric memory has attracted much attention due to its high density, fast read-write speed, non-volatile characteristics and radiation hardness. Recently, Bismuth Layer-Structured Ferroelectrics (BLSFs) have drawn much attention for its excellent fatigue-free properties.Bi₄Ti₃O₁₂(BTO)and Sr2 Bi 4 Ti 5 O1 8(SBTO) were selected as the researching objects. Using the PLD(pulsed laser deposition) to make the thin films. For integrating with the semiconductor technics and reducing the cost, commercial substrates Pt/TiO₂/SiO₂/Si was selected for the thin films to fabricate on.First, the BTO and SBTO ceramics was prePared by ball milling and sintering, then the best and optimized technics Parameter of BTO and SBTO films'deposition on Pt/TiO₂/SiO₂/Si substrate had been found, including the oxygen pressure and substrate temperature.Second, according to the reasons of fatigue, the oxide electrodes(SrRu O3 (SRO),LaSrCo O3 (LSCO),LaNi O3 (LNO)) were deposited on the Pt as films'electrode and buffer in order to improve its fatigue. The tests showed experimentally that the oxide electrode can change the films'orientation, the films'c-axis-oriented structure was effectively restrained, which improve its properties a lot, especially, the BTO films exhibited a fatigue-free.Then, the SBTO films were fabricated on Pt/TiO₂/SiO₂/Si substrate and the oxide electrodes, the tests showed that the SBTO films also had good properties, so the SBTO is a desirable and valuable material in the application of BLSFs, also it can be a good candidate of BTO.