影响磁控溅射制备PST/Si薄膜介电特性的几个因素

Analysis of Factors Affecting the Dielectric Characteristics of Si-Based(Pb_(1-x)Sr_x) TiO_3 Film Grown by Magnetron Sputtering

采用磁控溅射制备了Si基(Pb1-xSrx)TiO3(简称PST/Si)薄膜。测试表明,热处理工艺对PST/Si薄膜介电特性有着一定的影响,适当温度、适当时间的热处理可得到均匀致密的膜层及生长良好的晶粒,从而确保PST薄膜良好的介电特性。样品上电极材料对介电特性也有重要影响。Al较Au电极易氧化,从而易在其与PST薄膜的界面形成一氧化层,增加了串联电阻,导致介电损耗总体上要低。工作频率对材料的介电弛豫特性及漏电导等也会产生影响。

The （Pb1-xSrx）TiO3（PST） ferroelectric films were grown on Si substrates by magnetron sputtering. Its surface microstuructures were characterized with atomic force microscopy（AFM）. The influenee of various growth conditions, including electrode materials, sputtering power , gas flow rate, substrate temperature, annealing temperature and annealing time, etc., on film properties was studied. The results show that the annealing temperature and annealing time significantly affect the grain sizes and eompacmess of the films, which, in turn, influence the dieletuic characteristics. And the electrodes materials, say A1, on PST surface more easily oxidize than Au, increasing the series resistance and decreasing the dieletuic loss. Moreover, the operating frequency inversely affects the dieletuic relaxation and leakage conductance of the film.