Improvement of Resistive Switching Characteristics in Zinc Oxide-Based Resistive Random Access Memory by Ammoniation Annealing
Peiyu Wu, Hao-Xuan Zheng, Chih‐Cheng Shih, Ting‐Chang Chang, Wei-Jang Chen, Chih-Cheng Yang, Wen‐Chung Chen, Mao‐Chou Tai, Yung‐Fang Tan, Hui‐Chun Huang, Xiaohua Ma, Yue Hao, Tsung‐Ming Tsai, Simon M. Sze
Abstract
In this experiment, the electrical performance of zinc oxide based-resistive random access memory (RRAM) is successfully improved by using annealing in ammonia hydroxide solution at low-temperature and high pressure to complete ammonium-doped ZnO based-RRAM. The results of material analysis indicate that using CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> as ammonia hydroxide carrier during the annealing process leads to the reduction in dangling bond density. This can be clearly observed in the decrease in breakdown voltage during the forming process and a lower operating current during operation. Furthermore, in this ammonium-doped ZnO based-RRAM, we study the molecular doping of NH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> in ZnO, where the endurance and retention properties are improved as well. These improvements can be attributed to the higher concentration of nitrogen in the switching layer, which can effectively control the active oxygen ions during the operation process.