摘要
以Ta,TaN为衬底,采用原子层淀积方法制备高介电常数HfO2介质,比较研究了不同衬底电极对金属-绝缘体-金属(MIM)电容的性能影响.结果表明,采用TaN底电极能够获得较高的电容密度和较小的电容电压系数(VCC),在1MHz下的其电容密度为7.47fF/μm2,VCC为356ppm/V2和493ppm/V,这归因于TaN底电极与HfO2介质之间良好的界面特性.两种电容在3V时漏电流为5×10-8A/cm2左右,基于TaN底电极的MIM电容表现出具有较高的击穿强度,其在室温下的导电机理为肖特基发射.
Based on atomic-layer-deposited high permittivity HfO2 films on both Ta and TaN substrates, we compare the influence of different bottom electrodes on electrical performance of metal-insulator-metal （MIM） capacitors. The experimental results indicate that the TaN bottom electrode can give higher capacitance density （7.47 fF/μm^2 ） and smaller voltage coefficients of capacitance （356 ppm/V2 and 493 ppm/V）, which are attributed to the high quality interface between TaN bottom electrode and HfO2 dielectric films. Moreover, a low leakage current of - 5 × 10^- 8A/cm^2 at 3 V is achieved for both types of capacitors, and TaN bottom electrode-based MIM capacitors exhibit higher breakdown field. Finally, the conduction mechanism of the TaN-based capacitor is studied, showing a Schottky emission at room temperature.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2009年第5期3433-3436,共4页
Acta Physica Sinica
基金
国家自然科学基金(批准号:90607023)资助的课题~~
