SrTiO3金属-绝缘体-半导体结构的介电与界面特性

采用金属有机分解法在p型Si衬底上制备了SrTiO3（STO）薄膜.研究了STO薄膜金属 绝缘体 半导体(MIS)结构的介电和界面特性.结果表明，STO薄膜显示出优异的介电性能，在10kHz处的介电常数约为105，损耗低于001，这来源于多晶结构和良好的结晶性；MIS结构中的固定电荷密度Nf和界面态密度Dit分别约为15×1012cm-2和(14—35)×1012cm-2eV-1，这主要与Si/STO界面处形成的低介电常数界面层有关. 关键词： SrTiO3薄膜 MIS结构 介电性能 Si/STO界面

Dielectric and interface characteristics of SrTiO3 with a MIS structure

SrTiO3 (STO) films were deposited onto the p type Si substrates by metal organic decomposition (MOD) technique. The dielectric and interface characteristics of STO with a metal insulator semiconductor(MIS) structure were investigated. The results showed that the dielectric constant was about 105 and the dissipation factor was lower than 001 for our STO films at a frequency of 10kHz. The excellent dielectric properties were attributed to the polycrystalline structure with good crystallinity. The fixed charge density Nf and the interface trap density Dit were calculated to be about 15×1012cm-2 and (14—35)×1012cm-2eV-1, respectively. Both Nf and Dit were mainly connected with an interface layer with low dielectric constant formed at the interface of Si/STO.