DEVELOPMENT OF NOVEL THIN FILM VARISTORS BY CHEMICAL SOLUTION DEPOSITION

本文研究了化学溶液沉积法在低温下制备新型薄膜压敏电阻器。综合考虑起始材料、化学添加剂和加热工艺，可以成功制备具有绝缘体/半导体/绝缘体结构的SrTiO_3/Nb:SrTiO_3/SrTiO_3层状薄膜。制备的薄膜压敏电阻器具有典型的非线性V-I特性。ESCA分析表明，即使在700℃热处理后，La、Ni、Nb等金属元素的层间扩散也很小。500 nm厚度薄膜的非线性系数和压敏电压分别为4.5和38kV/cm^<-1>。发现钙钛矿LaNiO_3电极膜在衬底上的取向受前驱体溶液浓度的控制。这些结果可用于集成IC系统的新型压敏电阻的加工和开发。

This work focused on the low temperature processing of novel thin film varistors by chemical solution deposition method. Fabrication of SrTiO_3/Nb:SrTiO_3/SrTiO_3 layered films with insulator/semiconductor/insulator structure could successfully synthesized by considering the starting materials, chemical additives, and heating procedures. The typical non-linear V-I character was successfully observed for the prepared thin film varistors. ESCA analysis revealed that the interlayer diffusion of the metal elements such as La, Ni, Nb was negligiblly small even after heat treatment at 700℃. Non-linear coefficient and varistor voltage for the thin film with 500 nm thickness were confirmed to be 4.5 and 38kV/cm^<-1>, respectively. The orientation of perovskite LaNiO_3 electrode films on the substrate found to be controlled by the concentration of precursor solutions. These results can be applied for processing and development of the novel varistor integrated with IC system.