Showing posts with label Neural. Show all posts
Showing posts with label Neural. Show all posts

Jan 11, 2024

[paper] Neural Compact Modeling Framework

Eom, Seungjoon, Hyeok Yun, Hyundong Jang, Kyeongrae Cho, Seunghwan Lee, Jinsu Jeong, and Rock‐Hyun Baek
Neural Compact Modeling Framework for Flexible Model Parameter Selection with High Accuracy and Fast SPICE Simulation
Advanced Intelligent Systems (2023): 2300435
DOI: 10.1002/aisy.202300435

Department of Electrical Engineering, Pohang University of Science and Technology, Pohang 37673 (KR)

Abstract: Neural compact models are proposed to simplify device-modeling processes without requiring domain expertise. However, the existing models have certain limitations. Specifically, some models are not parameterized, while others compromise accuracy and speed, which limits their usefulness in multi-device applications and reduces the quality of circuit simulations. To address these drawbacks, a neural compact modeling framework with a flexible selection of technology-based model parameters using a two-stage neural network (NN) architecture is proposed. The proposed neural compact model comprises two NN components: one utilizes model parameters to program the other, which can then describe the current–voltage (IV) characteristics of the device. Unlike previous neural compact models, this two-stage network structure enables high accuracy and fast simulation program with integrated circuit emphasis (SPICE) simulation without any trade-off. The IV characteristics of 1000 amorphous indium–gallium–zinc-oxide thin-film transistor devices with different properties obtained through fully calibrated technology computer-aided design simulations are utilized to train and test the model and a highly precise neural compact model with an average IDS error of 0.27% and R2 DC characteristic values above 0.995 is acquired. Moreover, the proposed framework outperforms the previous neural compact modeling methods in terms of SPICE simulation speed, training speed, and accuracy.

Fig: a) The structure of a-IGZO TFT structure simulated with TCAD
b) Calibrated a-IGZO sub-gap DOS

Acknowledgements: This work was supported in part by the LG Display Company, in part by the Brain Korea 21 Fostering Outstanding Universities for Research (BK21 FOUR) program, in part by Institute of Information and Communications Technology Planning and Evaluation (IITP) grant funded by the Korea government (MSIT) (grant no. 2019-0-01906, Artificial Intelligence Graduate School Program [POSTECH]), in part by the Ministry of Trade, Industry and Energy (MOTIE) under grant no. 20020265, in part by Korea Semiconductor Research Consortium (KSRC) support program for the development of the future semiconductor device, and in part by the Technology Innovation Program (grant no. RS2023-00231985) funded by the Ministry of Trade, Industry and Energy (MOTIE, Korea) (grant no. 1415187390).









Jul 12, 2023

[paper] Bionic Neural Probe

Yu Zhou, Huiran Yang, Xueying Wang, Heng Yang, Ke Sun, Zhitao Zhou, Liuyang Sun, Jianlong Zhao, Tiger H. Tao and Xiaoling Wei
A mosquito mouthpart-like bionic neural probe
Microsystems & Nanoengineering volume 9, Article number: 88 (2023)
DOI: 10.1038/s41378-023-00565-5

Abstract: Organic electronics can be biocompatible and conformable, enhancing the ability to interface with tissue. However, the limitations of speed and integration have, thus far, necessitated reliance on silicon-based technologies for advanced processing, data transmission and device powering. Here we create a stand-alone, conformable, fully organic bioelectronic device capable of realizing these functions. This device, vertical internal ion-gated organic electrochemical transistor (vIGT), is based on a transistor architecture that incorporates a vertical channel and a miniaturized hydration access conduit to enable megahertz-signal-range operation within densely packed integrated arrays in the absence of crosstalk. These transistors demonstrated long-term stability in physiologic media, and were used to generate high-performance integrated circuits. We leveraged the high-speed and low-voltage operation of vertical internal ion-gated organic electrochemical transistors to develop alternating-current-powered conformable circuitry to acquire and wirelessly communicate signals. The resultant stand-alone device was implanted in freely moving rodents to acquire, process and transmit neurophysiologic brain signals. Such fully organic devices have the potential to expand the utility and accessibility of bioelectronics to a wide range of clinical and societal applications.

FIG: Multifunctional biomimetic neural probe system, with multichannel flexible electrode array and high sensitivity sensor array.