An influence of bottom electrode material on electrical conduction and resistance switching of TiOx thin films

作者：Kim Ngoc Pham^*; Trung Do Nguyen; Thi Kieu Hanh Ta; Khanh Linh Dao Thuy; Van Hieu Le; Duy Phong Pham; Cao Vinh Tran; Mott Derrick; Maenosono Shinya; Kim Sang Sub; Lee Jaichan; Duc Thang Pham; Bach Thang Phan

来源：The European Physical Journal - Applied Physics, 2013, 64(3): UNSP 30102.

DOI：10.1051/epjap/2013130255

We investigated the electrical conduction and resistance switching mechanisms of TiOx thin films grown on three kinds of bottom electrode at room temperature (an inert Pt, an active Ti and fluorine tin oxide FTO electrodes). The bottom electrode materials strongly affect the I-V characteristics and switching parameters. The I-V characteristic is explained through the presence of interface states in the metal electrode devices (Pt and Ti) and the work function in the metal oxide device (FTO). The Pt device has the smallest V-SET and largest switching ratio, while the Ti device shows the largest VSET and smallest switching ratio. XPS data shows non-lattice oxygen in TiOx films. Therefore, the proposed bipolar resistance switching arises from formation and rupture of filament paths, generated by the movement of oxygen vacancies. All devices depict the same electrical conductions, trap-controlled space-charge-limited, FN tunneling and Ohmic conductions for a high resistance state and a low resistance state, respectively. In this study, the rarely reported FN tunneling conduction in published TiOx-based ReRAM device was found, which can be attributed to an influence of the bottom electrode on the electronic distribution in devices.

• 出版日期2013-12