PhD student and research assistant, The University of Texas at Austin
Built-in Nonlinear Characteristics of Low Power Operating One-Resistor Selector-less RRAM
The sneak-path leakage current issue is one of the severe hindrances for the application of high density resistive random access memory (RRAM) array design. In this work, we demonstrate nonlinear (NL) resistive switching characteristics of HfOx/SiOx-based stacking structure as a realization for selector-less RRAM devices. The NL characteristic was obtained and designed by optimizing internal filament location with low effective dielectric constant intending in HfOx/SiOx structure. First, the stacking HfOx/SiOx-based RRAM device as the one-resistor-only memory cell is applicable without additional selector device to solve the sneak-path issue with switching voltage ~1 V, which is desirable for low power operating in built-in nonlinearity crossbar array configuration. Second, low voltage (~1V) ambient-independent resistive random access memory (AI-RRAM) has been observed in a Pt/HfOx/SiOx/TiN one-resistor (1R) memory cell with intrinsic nonlinear behavior, which improves read/write immunity to sneak path issues for future large-scale array design. The conductive silicon-rich crystalline structure in filamentary region has been observed in single-layered SiOx device by TEM and X-ray diffraction, and discussed the potential knowledge bridge in SiOx resistive switching phenomena. The HfOx/SiOx stacked structure also shows excellent resilience to ambient changes, i.e. air, vacuum, nitrogen through inserting an interface structure providing high defect density and Hf-encapsulation of the filamentary region as compared to single-layered structures. In the future research scope, neuromorphic computing by using the bilayer RRAMs as synapses is likely to be realized attributed to the intrinsic beauty i.e. modulating conductance and spike-timing dependent plasticity (STDP).
I am a PhD student in the Department of Electrical and Computer Engineering (ECE) at The University of Texas at Austin since 2014. I received the B.S. degrees in electrical engineering from National Chiao Tung University, Taiwan in 2011; the M.S. degree in Electronics Engineering from National Chiao Tung University in 2014. From March to August 2017, I’m a hardware developer (Internship) at the IBM located East Fishkill, NY, and working on inline functional characterization and modeling. I was a graduate research assistant at The University of Texas at Austin since 2014. I have published over 20 journal publications and 12 conference proceedings, and has been awarded numerous academic research awards. At the University of Texas at Austin, I focus on the topics of current research on resistive switching memory used in next generation non-volatile memory application and wearable epidermal electronic devices.