As we continue to expand our understanding of computing, the traditional von Neumann computers are increasingly shifting towards neuromorphic architectures. Grasping the intricacies of neural information processing is now pivotal for the progression of contemporary computing. The brain, in contrast to von Neumann machines, is distinguished by its extensive parallelism, ultra-high 3D density, low power consumption, and adaptive learning capabilities. To advance computing technology, I believe the optimal strategy is to establish a hybrid electronic platform that leverages both the strength of CMOS and the innovative capabilities of new nanodevices. Our objective is to explore the future of computing and electronics at large by harnessing new structures, devices, materials, ideas, and engineering principles.

3-D integration and wafer-level packaging

Current applications of interest include: Integration of 3D memories (RRAM, FeRAM) on CMOS Wafer-level bonding and its reliabiltiy Merging of different substrate technology Related projects: Development of CXL-based PIM (Processor in Memory) semiconductor technology with memory coherency for multiple DRAM modules Novel Highly Reliable ReRAM based PIM Device, Circuit, Architecture Development for Sequential Data Processing and Image Recognition Applications Development of ultra-thin 3D integration process technology (Samsung) Ultra-small pixel micro LED display manufacturing technology

Related Publications

• Hyun, Gihwan, et al.,and Seunghyun Lee “CMOS-Integrated Ternary Content Addressable Memory using Nanocavity CBRAMs for High Sensing Margin.” Small IF 13.3 (2024)

• Bae, Junseong, et al.,and Seunghyun Lee “Optimizing Ultra-thin 2D Transistors for Monolithic 3D Integration: A Study on Directly Grown Nanocrystalline Interconnects and Buried Contacts.” Advanced Materials IF 29.4 (2024)

• Junho Bae, YuSeop Shin,et al.,and Seunghyun Lee “Quantum dot-integrated GaN light-emitting diodes with resolution beyond the retinal limit” Nature Communications IF 14.9 (2022)

• Batyrbek Alimkhanuly,et al.,and Seunghyun Lee “Graphene-based 3D XNOR-VRRAM with ternary precision for neuromorphic computing” Nature Partner Journal: 2D materials & applications IF 11.1 (2021)

• Seunghyun Lee, Zhaohui Zhong, ‘‘Nanoelectronic circuits based on two-dimensional atomic layer crystals", Nanoscale, 6(22) 13283-13300. (2014)

• Seunghyun Lee, Kyunghoon Lee, Chang-Hua Liu, Girish S. Kulkarni, and Zhaohui Zhong, ‘‘Flexible and Transparent All-Graphene Circuits for Quaternary Digital Modulations", Nature Communications, 3, 1018 (2012).

• Seunghyun Lee, Seow Yuen Yee, Ali Besharatian, Hanseup Kim, and Khalil Najafi, ‘‘Adaptive gas pumping by controlled timing of active microvalves in peristaltic micropumps", in IEEE Solid-State Sensors, Actuators and Microsystems, Denver, Colorado.

• Li, Ling, Xiangyu Chen, Ching-Hua Wang, Ji Cao, Seunghyun Lee, Alvin Tang, Chiyui Ahn, Susmit Singha Roy, Michael S. Arnold, and H-S. Philip Wong. “Vertical and Lateral Copper Transport through Graphene Layers.” ACS nano 9, no. 8 (2015): 8361-8367.

Memory Technology and Neuromorphic Hardwares

Current applications of interest include: Memristor Fault-Aware Neuromorphic System for 3D Memristor array Memristor implementation of binary neural network and XNOR-net Neuromorphic hardware for Near/In memory computing and edge devices Ultralow power artifical neurons in vertical cross-point architecture Related projects: Memristor Fault-Aware Neuromorphic System for 3D Memristor array Development of CXL-based PIM (Processor in Memory) semiconductor technology with memory coherency for multiple DRAM modules Developing Re-RAM-bsed a near-memory bit-vector computing unit Novel Highly Reliable ReRAM based PIM Device, Circuit, Architecture Development for Sequential Data Processing and Image Recognition Applications

Related Publications

• Hyun, Gihwan, et al.,and Seunghyun Lee “CMOS-Integrated Ternary Content Addressable Memory using Nanocavity CBRAMs for High Sensing Margin.” Small IF 13.3 (2024)

• Patil, Shubham V., et al.,and Seunghyun Lee “Spike-time dependent plasticity of tailored ZnO nanorod-based resistive memory for synaptic learning.” Journal of Science: Advanced Materials and Devices (2023)

• Batyrbek Alimkhanuly,et al.,and Seunghyun Lee “Graphene-based 3D XNOR-VRRAM with ternary precision for neuromorphic computing” Nature Partner Journal: 2D materials & applications IF 11.1 (2021)

• Vo, Quang Hieu,et al.,and Seunghyun Lee “Hardware Platform-Aware Binarized Neural Network Model Optimization.” Applied Sciences (2021)

• Muhammad Salman Ali,et al., “ERDNN: Error-Resilient Deep Neural Networks With a New Error Correction Layer and Piece-Wise Rectified Linear Unit”, IEEE Access IF 3.74 (2020)

• Sunghwan Lee,et al., and Seunghyun Lee, “Metal oxide resistive memory with a deterministic conduction path”, Journal of Materials Chemistry C, IF 7.4 (2019)

• Shem Seo, Jinho Lim, Sunghwan Lee, Batyrbek Alimkhanuly, Arman Kadyrov, Dasom Jeon, Seunghyun Lee, “Graphene-edge electrode on a Cu-based chalcogenide selector for 3D vertical memristor cells”, ACS Applied Materials & Interfaces IF 9.2 (2019)

• Seunghyun Lee, Joon Sohn, Zizhen Jiang, Hong-Yu Chen, and H. -S. Philip Wong, ‘‘Metal Oxide Resistive Memory using Graphene Edge Electrode", Nature Communications 6, 8407 (2015).

• Ahn, Chiyui, Scott W. Fong, Yongsung Kim, Seunghyun Lee, Aditya Sood, Christopher M. Neumann, Mehdi Asheghi, Kenneth E. Goodson, Eric Pop, and H-S. Philip Wong. ‘‘Energy-efficient phase-change memory with graphene as a thermal barrier", Nano Letters 15, no. 10 (2015): 6809-6814.

• Seunghyun Lee, Joon Sohn (co-1st author), Zizhen Jiang, Hong-Yu Chen and H.-S. Philip Wong, ‘‘Atomically Thin Graphene Plane Electrode for 3D RRAM", IEDM, paper 5.3, pp. 116-119, (2014)

• Yang, Yuchao, Jihang Lee, Seunghyun Lee, CheHung Liu, Zhaohui Zhong, and Wei Lu. ‘‘Oxide Resistive Memory with Functionalized Graphene as Built?in Selector Element", Advanced Materials 26, no. 22 (2014): 3693-3699.

Thermal Management of Electronics

Current applications of interest include: Heat management of systems using anistropic heat transfer materials Thermal analysis of 3D vertical architectures Temperature dependent carrier transfer characteristics Related projects: Reliability Improvement of GaN devices utilizing the anistropic thermal conductance of 2D materials Ultra-small pixel micro LED display manufacturing technology Development of ultra-thin 3D integration process technology (Samsung)

Related Publications

• Yuseop shin, Junho Bae,et al., and Seunghyun Lee, “Coupled thermo–electrical analysis of highly scaled GaN micro-LEDs with meshed hybrid conductors”, Semiconductor Science and Technology (2019)

• Dasom Jeon, Jinho Lim, Junho Bae, Arman Kadirov, Yongsu Choi, and Seunghyun Lee “Suppression of self-heating in nanoscale interfaces using h-BN based anisotropic heat diffuser”, Applied Surface Science IF 6.7 (jcr 2.3%) , (2021)

• Ahn, Chiyui, Scott W. Fong, Yongsung Kim, Seunghyun Lee, Aditya Sood, Christopher M. Neumann, Mehdi Asheghi, Kenneth E. Goodson, Eric Pop, and H-S. Philip Wong. ‘‘Energy-efficient phase-change memory with graphene as a thermal barrier", Nano Letters 15, no. 10 (2015): 6809-6814.

Sensors, Actuators, MEMS

Current applications of interest include: Unique structures (3D vertical, HEMT, junction transistor, TFT, Tunneling junction, Schottky junction, NEMS) Novel mechanisms (Ion, defect engineering, quantum confinement, floating gates, barrier conrol, ferroelectric) New materials (III-V, chalcogenide material, transition metal oxides, Nitrides, low-dimensional material) Related projects: Study on integrated multifunctional sensor platform based on autonomous energy Developement of radiation hardened electron devices based on functional nanomaterials

Related Publications

• Choi, Yongsu, et al.,and Seunghyun Lee “Active pixel image sensor array based on large-scale ReS2 semiconducting film.” Materials Science in Semiconductor Processing (2024)

• Venkatesan, A., et al.,and Seunghyun Lee “Air-stable, all-dry transferred ReS2/GaSe heterostructure-based NO2 gas sensor.” Journal of Materials Science & Technology, IF 10.9 (2024)

• Devnath, Anupom, et al.,and Seunghyun Lee “Real-time detection of mercury ions based on vertically grown ReS2 film.” Journal of Materials Science & Technology, IF 10.9 (2023)

• Ryu, Hyeyoon, et al.,and Seunghyun Lee “Enhanced performance of a photodetector based on a grapheneCVD-grown dendritic ReS2Ta2O5 vertical heterojunction.” Journal of Materials Chemistry C (2023)

• Junho Bae, YuSeop Shin,et al.,and Seunghyun Lee “Quantum dot-integrated GaN light-emitting diodes with resolution beyond the retinal limit” Nature Communications IF 14.9 (2022)

• Gankhuyag, Sukhbayar, et al.,and Seunghyun Lee “One-pot synthesis of SiO2@ Ag mesoporous nanoparticle coating for inhibition of escherichia coli bacteria on various surfaces.” Nanomaterials IF 5.1 (2020)

• Jinho Lim, Dasom Jeon, Sunghwan Lee, Jae Su Yu, and Seunghyun Lee, “Nucleation promoted synthesis of large-area ReS2 film for high speed photodetectors”, Nanotechnology, (2019)

• Seunghyun Lee, Alvin Tang, James P. McVittie, H. -S. Philip Wong, ‘‘NEM relays using 2-dimensional nanomaterials for low energy contacts", Energy Efficient Electronic Systems, pp. 1,2, (2013)

• Seunghyun Lee, Kyunghoon Lee, Chang-Hua Liu, Girish S. Kulkarni, and Zhaohui Zhong, ‘‘Flexible and Transparent All-Graphene Circuits for Quaternary Digital Modulations", Nature Communications, IF:11.33, 3, 1018 (2012). Link - Introduced in Science
  

• Seunghyun Lee, Seow Yuen Yee, Ali Besharatian, Hanseup Kim, and Khalil Najafi, ‘‘Adaptive gas pumping by controlled timing of active microvalves in peristaltic micropumps", in IEEE Solid-State Sensors, Actuators and Microsystems, Denver, Colorado, June. 21-25, (2009).

• Hanseup Kim, Seunghyun Lee, Khalil Najafi, “High force liquid gap electrostatic hydraulic micro actuator”, The 11th International Conference on Miniaturized Systems for Chemistry and Life Sciences (μTAS), pp. 1735-1737 (2007).