Along with the continuous downscaling of the critical dimension in semiconductor processes, sheet materials such as ultra shallow junctions (USJ) are widely used in the process development. Characterization and monitoring of implant and annealing technologies for USJ are significant metrology challenges. For several decades, conventional four-point probe measurement has been a useful metrology technique to characterize sheet resistance, sheet carrier density, and carrier mobility when combined with Hall Effect measurements. However, conventional four-point probes can cause large measurement errors on advanced micro or even nano-scale structures like USJ, unless the probe spacing can also be down scaled simultaneously with the devices under test. Recently, in-line micro four-point probe (M4PP) measurements have been proven to be an accurate method for characterization of USJ sheet resistance. In this report, both sheet resistance measurement and Hall effect measurement will be discussed. The measurement accuracy, measurement sensitivity and measurement reliability will be investigated in details.
Born in Anhui Province, Fei Wang received the B.S. degree in mechanical engineering from the University of Science and Technology of China, Hefei, China, in 2003 (supervisor: Prof. Wenhao Huang in the department of PMPI), and the Ph.D. degree in microelectronics from Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Science, Shanghai, China in 2008. After graduation, he joined in the Department of Micro- and Nanotechnology, Technical University of Denmark, working on micro four point probes for IC testing. Since 2010, he was promoted to assistant professor with the same department, directing a FTP funded project (~0.8 Million US dollars). He has published over 20 papers in the top-level journals and conferences in MEMS field such as the IEEE Journal of MEMS, JMM, IEEE IEDM conference and IEEE MEMS conference. He is also the inventor for two Chinese patents and one WIPO patent. His research interests include MEMS fabrication and design, IC device testing, energy harvesting devices, and optical fiber sensors.
Personal homepage: www.staff.dtu.dk/fewa