Over the past few years we have investigated applications of Mixed-Ionic-Electronic-Conduction (MIEC) materials as access devices for various non-volatile memory candidates, such as Phase Change Memory (PCM), Resistive RAM (RRAM), conducting bridge RAM (CBRAM) and spin torque transfer MRAM (STT-MRAM). In this talk we describe the transformational role of conducting atomic force microscopy in the discovery of new mixed ionic electronic conductors, for spatially localized (sub-20nm) and fast pulse characterization (sub-50ns) of MIEC thin-films & devices and for memory devices based on RRAM, CBRAM and MRAM. C-AFM measurements on MIEC and memory devices yield fast, reliable and statistically relevant information that can be applied towards the discovery of materials, electrodes, anneal conditions and a host of other parameters relevant for ultimate device performance. From an instrumentation perspective, we show how thousands of I-V (current vs. voltage) measurements can be both repeatable and reliable. We describe how to overcome C-AFM challenges such as set-up inconsistency, non-repeatable I-V performance, probe life and lack of large statistics. One-to-one correlations between data from automated probe testing and C-AFM measurements, and unique fabrication knowledge and extensive device scaling data obtained via C-AFM will be presented.
Dr. Kumar Virwani is a Research Staff Member at the IBM Almaden Research Center in San Jose, California. He obtained Bachelor of Engineering (BE) degree from the University of Mumbai, India and MS and PhD degrees (in 2007) from the University of Arkansas at Fayetteville, USA. Dr. Virwani joined IBM Almaden Research Center in 2008 where his research activities include application of electrical SPM techniques to analyze mixed ionic electronic conduction materials/devices, non-volatile memory materials/devices, nanoindentation of low-K dielectrics and Auger spectroscopy. Prior to joining IBM he worked at Bruker Nano (formerly Veeco Instruments) on various aspects of scanning probe microscopy.