Nitrogen ratio and RTA optimization on sputtered TiN/SiO2/Si electrolyte-insulator-semiconductor structure for pH sensing characteristics

作者：Ren, Chang; Yang, Chia-Ming^*; Lyu, Chengang; Hsu, Chin-Yuan; Chen, Tsung-Cheng; Wang, Hau-Cheng; Yang, Hao; Lin, Wei-Tse; Juan, Pi-Chun; Huang, Chi-Hsien; Pijanowska, Dorota G.; Wang, Jer-Chyi; Tsai, Jung-Ruey

来源：Vacuum, 2015, 118: 113-117.

DOI：10.1016/j.vacuum.2015.02.025

• pH sensitivity
• EIS
• TiN
• Sputtering
• RTA

Sputtered titanium nitride (TiN) with a novel N-2 ratio adjustment and rapid thermal annealing (RTA) treatment are proposed in order to optimize pH sensing performance of electrolyte-insulator-semiconductor (EIS) structure. Selection of this methodology, which can be easily applied into standard CMOS and DRAM technology, results from the fact that TiN is a well-verified material as a buffer or a barrier layer. It was concluded that pH sensitivity of the order of 60.5 mV/pH and linearity of 99.9% could be obtained for a TiN/SiO2 EIS structure treated with N-2 ratio of 20% and RTA at 800 degrees C, which could be a good candidate in sensor applications. This performance is stable for more than two months. Higher surface roughness shown in atomic force microscope (AFM) analysis and high oxygen level in sputtering process shown in x-ray photo photoelectron spectroscopy (XPS) could be the reasons for the high sensitivity of the fabricated TIN sensing layer.

• 出版日期2015-8
• 单位长春大学; 中国医科大学; 天津大学