Atomic force microscopy developments for probing space charge at sub-micrometer scale in thin dielectric films

• Published in: IEEE transactions on dielectrics and electrical insulation Vol. 23; no. 2; pp. 713 - 720
• Main Authors: Villeneuve-Faure, C., Boudou, L., Makasheva, K., Teyssedre, G.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2016; The Institute of Electrical and Electronics Engineers, Inc. (IEEE); Institute of Electrical and Electronics Engineers
• Subjects: Atomic force microscopy; dielectric materials; Dielectrics; Electric potential; Electrical insulation; electrostatic force; Electrostatic measurements; Electrostatics; Engineering Sciences; Force; Force measurement; Kelvin force microscopy; Microscopy; Origins; Space charge; Surface topography; Thin films
• ISSN: 1070-9878; 1558-4135
• DOI: 10.1109/TDEI.2016.005319

Charge injection and accumulation in dielectrics are phenomena at the origin of different kind of failure of devices. To improve the understanding of involved mechanisms, space charge measurement techniques have been successfully developed. However, their spatial resolution is incompatible with thin films or interfaces studies. In this paper, the contribution of techniques derived from Atomic Force Microscopy (AFM) to space charge measurement is investigated. First of all, localized charges injection is studied using classical Kelvin Force Microscopy (KFM). Secondly, we propose a new method called EFDC (Electrostatic Force Distance Curve) which allows direct measurement of electrostatic force induced by trapped charges. EFDC sensitivity to lateral localization of charges is demonstrated. Finally, comparing the results obtained by EFDC and KFM highlights the relative merit of each technique.