6月16日上午，由北京大学集成电路学院、集成电路高精尖创新中心、北京大学国家集成电路产教融合创新平台、集成电路科学与未来技术北京实验室、后摩尔时代微纳电子学科创新引智基地及北京大学校友会半导体分会联合主办的“未名·芯”论坛系列讲座第六十期在北京大学微纳电子大厦103报告厅成功举行。本期论坛特邀韩国科学技术院Mincheol Shin教授，带来了题为《Quantum Transport Simulations of Oxide Semiconductor Devices: A First-principles-based Multiscale Framework》的讲座。讲座由北京大学集成电路学院刘飞研究员主持。
Shin教授首先指出，为了满足快速周转时间的需求，传统的漂移-扩散TCAD工具是不可或缺的，但许多量子效应在漂移-扩散模型中并没有被体现。同时随着技术的进步，制造时间和成本均不断攀升，亟需开发既精确又实用的量子力学仿真工具。接着，Shin教授介绍了其团队在c-IGZO沟道器件仿真的工作，Shin教授团队发展了第一性原理级别的无序输运计算的有效模型，使用DFT方法计算体系的透射率，并使用随机替换离子来引入无序，该方法计算的迁移率和实验结果取得巨大的一致性。因为DFT方法计算依然耗时，将离子替换视为能量差别构建有效模型，同时使用利用模式空间方法最终可以取得107的加速效果。Shin教授还展示了c-IGZO器件的关键仿真发现，包括通过调控In或Zn组分提升载流子迁移率等重要规律。
随后，Shin教授介绍了模式空间加速计算的方法，各种模式空间方法的思路均为降低哈密顿量维度来加速计算，Shin教授的方法为通过选取一组和输运相关的基组和能量区间重构哈密顿量，此方法可以极大地降低哈密顿量维度，如在粗糙界面的硅纳米线中，可以将哈密顿量维度从1000降至约50。更特别地，在高度震荡电势的IGZO中，此方法仅仅选用3个模式便可以比一般模式空间方法中134个模式的结果优异。
最后，Shin教授介绍了团队其他工作，如DFT-NEGF器件仿真方法、金属互连线中晶界掺杂问题、基于机器学习的器件优化、PINN器件仿真方法、NNH-MD方法加速计算、ML-based模式空间方法、面向铁电器件的五场耦合相场建模工具等工作。
在最后的互动环节中，Shin教授与现场师生就器件仿真方法、模式空间方法等内容展开了深入地交流与讨论，探讨了仿真方法中的计算细节与技术，为在场师生带来了深刻的启发。
个人简介：
Mincheol Shin received the B.S. degree from Seoul National University, Seoul, Korea, in 1988 and the Ph.D. degree from Northwestern University, Evanston, IL, in 1992, both in physics. From 1993 to 2002, he was with the Basic Research Department, Electronics and Telecommunications Research Institute, Daejeon, Korea, as a Senior Researcher. In 2002, he joined the faculty of School of Engineering, Information and Communications University, Korea. As the university was merged with Korea Advanced Institute of Science and Technology (KAIST) in 2009, he is currently a full professor in the Electrical Engineering department at KAIST. In 2008 and 2014, he spent his sabbatical years as a visiting scholar at ECE department of Purdue University, IN, USA, and Korea Institute of Science and Technology, respectively. His research interest has focused on developing in-house simulation tools for nanoelectronic devices, specializing in advanced electronic transport calculations utilizing quantum mechanical methodologies. He has investigated electron, phonon, spin transport in various novel nanoscale logic and memory devices. He also has a keen interest in disseminating research tools for community use, as he is a principal developer of the nanoelectronics tools hosted on nanoHUB and led a government-funded collaborative project to deliver these technological resources for education and research. In 2021, he served as the chair of IWCN, the computational electronics community workshop.
