CHARACTERISTIC OF (100)-TEXTURED (Pb_xSr_(1-x))TiO_3 THIN FILMS USED FOR DRAM AND TUNABLE DEVICE APPLICATION

摘要

The Pb_xSr_(1-x))TiO_3 (PST) thin films were deposited on LaNiO_3 (LNO(100))/ Pt/Ti/SiO_3/Si substrates electrode by RF-magnetron sputtering using three different Pb target composition ranging from 32.5 percent approx 37.5 percent and different process condition. Structural and dielectric properties of the PST thin films for tunable microwave and DRAM application were investigated. The PST thin films deposited at 400 deg C show higher dielectric constant than those post-annealed at 600 deg C because of better crystallization. The former also have lower leakage current around 10~(-8) A/cm~2 up to applied field of 350 kv/cm, which is suitable for DRAM application. On the other hand, the post-annealed PST thin films have satisfactory tunability around 58 percent and figure of merit around 30, which are more suitable for microwave device application.