Study of leakage current of High-K dielectrics

• Main Author: Yan, Lina
• Other Authors: Wang Junling
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Materials::Microelectronics and semiconductor materials::Thin films
• Online Access: http://hdl.handle.net/10356/15235
• Institution: Nanyang Technological University

BST thin film is one of the metal oxides that show high dielectric constant and very good dielectric properties such as long lasting time, low dielectric lose or fast electric response. Another interesting property of this material is that it shows resistive switching behavior with the help of oxygen vacancies inside. In this project BST thin film with thickness around 80nm was investigated in the form of Pt-BST-Au capacitors. I-V characteristic of this capacitor was measured. Biasing this capacitor at high voltage and temperature, which is believed to move oxygen vacancies in BST thin film, affects the barrier height at the interface. Barrier height of top and bottom interface of this capacitor was calculated based on Schottky conduction mechanism I-V relationship. Comparing the calculated barrier height before and after biasing, we observe results that are quite consistence with the predictions. From the results we can conclude that motion of oxygen vacancies in BST thin film is possible under biasing. Switching of BST thin film resistance can be done by applying external electric field at a certain temperature.