On the afternoon of January 25, 2018, by the invitation of the key laboratory for special functional materials of MOE, Dr. Guanzhang Zhang from Shenzhen Graduate School of Peking University visited our laboratory for academic exchanges and made an academic report entitled "cryogenic supercritical fluid and device improvement technology". The report was chaired by deputy director Feng Bai, and some teachers and students of our laboratory attended the meeting.

Dr. Guanzhang Zhang first presented the concept of supercritical fluid from "defects in MOSFET transistors" and introduced the advantages of supercritical fluid technology. The supercritical fluid has the solubility similar to liquids and the penetration similar to gas. This technology can improve the characteristics of electronic devices closed to room temperature. Subsequently, Dr. Zhang introduced two kinds of commonly used supercritical substances, supercritical CO₂ and supercritical H₂O. Dr. Zhang also described the use of supercritical technology to effectively bring elements into the material and activate doping. For instance, the use of supercritical carbon dioxide can effectively modify the nitrogen element into AlGaN of the UV-C LED. The incorporation of nitrogen elements reduces the degree of defects concentration and will greatly improve the luminescence efficiency of UV-C LED. In addition, the cryogenic supercritical fluid treatment technology is effective and significant for resistance memory, thin film transistors, high power transistors, solar cells, and two dimensional material devices. Therefore, the supercritical fluid is an innovative technology and its development can enhance the performance of electronic devices.

After the report, Dr. Zhang held a heated discussion with the teachers and students and answered the questions in detail. Through this report, we recognized the characteristics and advantages of supercritical fluid technology, broadened our horizons and promoted the overall academic atmosphere of the laboratory.

Guanzhang Zhang: An outstanding scholar in the field of electronic engineering. He was graduated from Zhongshan University in Taiwan, China, and received the Ph. D. in 2014. He is now working in the Graduate School of Shenzhen, Peking University. His research work mainly engages in the application of the resistive memory and supercritical fluid technology, and series outstanding achievements have been made in the development of new electronic devices. In recent years, he had presided a number of horizontal scientific research projects with his partners from the Development of Advanced Digital Memory (RRAM) in Taiwan, China. Series achievements have been achieved, and advanced innovation research and teaching work have been carried out In the fields of thin film transistor (TFT), semiconductor memory, solar cell Solar cell, nanoscale devices and processing, photoelectric devices and green energy sources. He has been awarded by the the basic merit of youth teaching in Peking University in the field of electronic engineering. Moreover, he has also obtained 24 technical patents (including 5 US patents). His research achievements in supercritical fluid technology have attracted wide attention from domestic and international colleagues. Dr. Zhang published 35 papers in the IEEE EDL international authoritative journal, 20 papers in the Applied Physics Letters (APL) international authoritative journal, and 116 articles in SCI. He has 28 papers as first authors or communications authors and these work have been quoted by 1408 times, with the h-index of 24.