Research
Novel Access Device and Selectorless Resistance Random Access Memory (ReRAM)
My primary research focused on characterization of low power, one-resistor only (1R) selectorless RRAM as a solution for suppressing the sneak path current (SPC) and read error. The current results provided comprehensive insights of the device structure design and optimized operation approaches. Also, a model for device switching mechanisms is developed, which will be the key for realizing a low power ReRAM applications i.e. brain-inspired neurosynaptic computing for vision, audition, and multi-sensory fusion etc.
Ying-Chen Chen, Jack Lee, Chih-Yang Lin, "Dual-Functional Hybrid Selectorless RRAM and Selection Device for Memory Array Application", IEEE Transactions on Electron Devices (2021)
Ying-Chen Chen, Chao-Cheng Lin, Szu-Tung Hu, Chih-Yang Lin, Burt Fowler, and Jack Lee, "A Novel Resistive Switching Identification Method through Relaxation Characteristics for Sneak-path-constrained Selectorless RRAM application," Scientific Reports (2019)
Ying-Chen Chen*, Hui-Chun Huang, Chih-Yang Lin, Szu-Tung Hu, and Jack C. Lee “Selectorless Resistive Switching Memory: Non-uniform Dielectric Architecture and Seasoning Effect Determination for Low Power Array Applications”, AIP Advances (2019) (Featured on Cover)
Ying-Chen Chen*, Szu-Tung Hu, Chih-Yang Lin, Burt Fowler, Hui-Chun Huang, Chao-Cheng Lin, Sungjun Kim, Yao-Feng Chang, and Jack C. Lee, “Graphite-based Selectorless RRAM: Improvable Intrinsic Nonlinearity for Array Applications”, Nanoscale (2018)
Ying-Chen Chen*, Chih-Yang Lin, Hui-Chun Huang, Sungjun Kim, Burt Fowler, Yao-Feng Chang, Xiaohan Wu, Gaobo Xu, Ting-Chang Chang, and Jack C. Lee. "Internal Filament Modulation in Low-dielectric Gap Design for Built-in Selector-less Resistive Switching Memory Application." Journal of Physics D: Applied Physics (2018)
Helical-shaped Device
The dual functions on nano helical shaped memory have been presented, i.e., nonvolatile switching (NVS) and volatile switching (VS). The selectivity of volatile switching devices can be integrated as a selector device in a memory application. Meanwhile, the device's nonvolatile switching behavior has shown as the self-selective characteristic for suppressing the sneak path current in the high-density memory array without switch devices integration. The highly CMOS compatible materials as HfOx and WOx have been investigated and presented in this work as the candidates of embedded memory and selectors in future computational applications.
Chen, Ying-Chen, Sumant Sarkar, John G. Gibbs, Yifu Huang, Jack C. Lee, Chao-Cheng Lin, and Chang-Hsien Lin. "Nano Helical-Shaped Dual-Functional Resistive Memory for Low-Power Crossbar Array Application." ACS Applied Engineering Materials (2022).
Chen, Ying-Chen, Yifu Huang, Sumant Sarkar, John Gibbs, and Jack Lee. "Direct-Grown Helical-Shaped Tungsten-Oxide-Based Devices with Reconfigurable Selectivity for Memory Applications." Journal of Low Power Electronics and Applications 12, no. 4 (2022): 55.
Ying-Chen Chen, Sumant Sarkar, John Gibbs, Chao-Cheng Lin, Chang-Hsien Lin, "Dual-Functional Nano Helical-Shaped Devices for Self-rectified Memory and Selector Applications," 53rd IEEE Semiconductor Interface Specialists Conference (SISC) (2022).
John F. Hardy, John A. Castaneda, John Gibbs, Ying-Chen Chen, "Helical-shaped Tungsten Oxide as Active Layer with Dual Switching Behaviors for Emerging Memory Applications," 7th IEEE Electron Devices Technology and Manufacturing (2023).
Emerging post-CMOS solid-state devices: Synaptic Behaviors in Memory Devices for Bio-mimicking Applications
The device with biological synaptic behaviors by integrating metal oxide memristor with Si diodes is realized. Minimal synaptic power consumption due to sneak-path current is achieved and the capability for spike-induced synaptic behaviors (LTP, LTD, and STDP) is demonstrated, representing critical milestones for the use of metal oxide–based materials in future neuromorphic computing applications.
Yao-Feng Chang, Burt Fowler, Ying-Chen Chen, Fei Zhou, Chih-Hung Pan, Ting-Chang Chang and Jack C. Lee, “Demonstration of Synaptic Behaviors and Resistive Switching Characterizations by Proton Exchange Reactions in Silicon Oxide," Scientific Reports, (2016)
Sungjun Kim, Jia Chen, Ying-Chen Chen, Min-Hwi Kim, Hyungjin Kim, Min-Woo Kwon, Sungmin Hwang, Muhammad Ismail, Yi Li, Miao Xiangshui, Yao-Feng Chang, Byung-Gook Park “Neuronal dynamics in HfOx/AlOy-based homeothermic synaptic memristors with low-power and homogeneous resistive switching” Nanoscale (2018)
Ambient Sensory Responses on Emerging Memory Platform
The HfOx/SiOx stack structure shows with not only improved electrical performance but also excellent resistivity to ambient changes i.e. air, vacuum, nitrogen environment than single SiOx layer structures owing to oxygen reaction stabilization. The conductive silicon crystalline structure in filamentary region and resistive switching (RS) region were observed in single SiOx layer device by TEM and X-ray diffraction pattern. With the actual visualization of the switching pathway, the size of Si filament makes scaling to ultra small localized switching more feasible for low power cognitive sensory application.
Ying-Chen Chen*, Hui-Chun Huang, Chih-Yang Lin, Sungjun Kim, Yao-Feng Chang, and Jack C. Lee “Effects of ambient sensing on SiOx-based resistive switching and resilience modulation by stacking engineering” ECS Journal of Solid State Science and Technology (2018)