학술논문

Conduction mechanisms in thin RF sputtered Ta/sub 2/O/sub 5/ films on Si and their dependence on O/sub 2/ annealing
Document Type
Conference
Source
2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595) Microelectronics Microelectronics, 2002. MIEL 2002. 23rd International Conference on. 2:755-758 vol.2 2002
Subject
Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Radio frequency
Conductive films
Semiconductor films
Annealing
Leakage current
Dielectric materials
Temperature
Material storage
Capacitors
Dielectrics and electrical insulation
Language
Abstract
The effect of oxygen annealing at high temperature (873, 1123 K) on the conduction mechanism of RF sputtered Ta/sub 2/O/sub 5/ (26 nm) on Si has been investigated. It is established that the influence of oxygen treatment on the leakage current is beneficial for the films. A leakage current density as low as 10/sup -7/ A/cm/sup 2/ at 1 MV/cm applied field for annealed layers has been obtained. The current reduction is considered to be due to removal of certain structural imperfections present in the initial layers. The conduction mechanism of the as-deposited films is found to be of Poole-Frenkel type and a change of the conduction mechanism for the annealed films at medium fields (0.8-1.3 MV/cm) is established. It is concluded that the dominant conduction mechanism in the intermediate fields can be effectively controlled by appropriate technological steps.