阳极氧化法制备Ta_2O_5绝缘膜及性能研究

Fabrication and characterization of Ta_2O_5 dielectric films by anodic oxidation

采用阳极氧化法在纯Ta表面制备绝缘性优良的Ta2O5介质膜,分析阳极氧化制备Ta2O5膜的基本机理,讨论不同电解液、阳极氧化电压及热处理等工艺参数对Ta2O5膜性能的影响。利用XRD、EDS和AFM分析薄膜的组织结构和表面形貌,超高阻微电流测试仪测试Ta2O5绝缘膜漏电流特性和耐击穿电压,结果表明,磷酸电解液中添加适当乙二醇溶液能有效地防止"晶化",阳极氧化电压在125～150V范围内制备Ta2O5绝缘膜耐击穿电压能力强,经350℃/60min大气气氛下热处理Ta2O5薄膜,内部结构致密,能有效提高Ta2O5绝缘膜耐击穿电压。

In this paper tantalum oxide arrays with eximious dielectric films were fabricated on the surface of a pure tantalum sheet by direct electrochemical anodic oxidation. Essential mechanism of preparaing Ta2O5 by anodic oxidation was analysed. The parameters of the anodic oxidation such as different electrolyte, oxidation voltage and heat treatment influenced on properties of tantalum oxide were discussed. XRD,EDS ,AFM and current testing instrument with high resistance techniques have been used to characterize the Ta2O5 dielectric film. It shows that crystallization is effectively prevented when glycol is appened in the H3PO4 electrolyte. The resisitant breakdown voltage is strong as oxidation voltage is between 125 and 150V in which Ta2O5 dielectric films are fabricated. The intestine structure of Ta2O5 films is more compact at 350℃/60min in air atmosphere, by which the resisitant breakdown voltage of dielectric films availably enhances.