John Robertson is a Fellow of the Royal Society, of the UK Royal Academy of Engineers, the IEEE, APS and MRS. He has also been awarded the IEEE Cledo Brunetti Award for the choice of high K dielectric layers in FETs.

Non-linear Resistors and Selector Devices from Chalcogenides


John Robertson



The original amorphous semiconductors were chalcogenides like STAG (SeTeAsGe) glasses. Then with the discovery of bipolar doping in a-Si:H, Si was the dominant amorphous semiconductor for many years, due to photoconductivity, solar cells, and many other uses. Then amorphous oxide semiconductors came to dominate display applications. Our 2022 Mott lecture will describe the importance of bi-stable phase change memory materials (PCMs) and a return to chalcogendies. To help PCMs to function in X-Y cross point arrays, it is useful to have strongly non-linear conductors at low voltages to select the chosen location in these arrays and block ‘sneak paths’. These arise from non-volatile electronic switching in chalcogenides with related materials [1] used in computer memories, and add to the various types of function possible from amorphous semiconductors. The materials selection and conduction mechanism is covered.



[1]. H Li, J Robertson, Sci Reports 9 1867 (2019)

[2] S J Jia... M Liu, Nature Commun 11 4636 (2020).


Tutorial Speaker


John Robertson

Cambridge University

Tutorial (10:20-11:20, 23rd Aug,Zhongda Lecture Hall (中大报告厅))


Cambridge University


Department of Engineering, Cambridge University, Cambridge, UK





Tutorial: John Robertson