Working Report in 2023: SID Student Branch at SNU chapter

The SID Student Branch at Seoul National University (SNU) is aimed to offer various programs including paper presentation, exhibition, and seminar.

∙ Officer

- Faculty advisor: Prof. Yongtaek Hong (E-mail: yongtaek@snu.ac.kr, Homepage: http://axel.snu.ac.kr)
- Chair: Ms. Sujin Jeong (audio0427@snu.ac.kr)
- Vice-Chair: Mr. Hanul Kim (withsk21@snu.ac.kr)
- Treasurer: Mr. Jinsu Yoon (jsyun34@snu.ac.kr)
- Secretary: N/A

<Activities in 2023>

1. Display Open-lab: May 8, 2023, Building 104-1, Seoul National University, Seoul, Korea

<Photographs of display center open house event>

Students participated in the exhibition of Samsung display for display center open-house event, and our lab made an overall introduction of the research scope to the undergraduate students visited our lab.

2. SID Display Week 2023: May 21 – 26, 2023, Los Angeles Convention Center, Los Angeles, USA.

6 students participated in the symposium, and five presented the works as below:

∙ Hyunjun Yoo et al., “Temporal Photo-response Analysis of Inkjet-printed Transparent Single-walled Carbon Nanotube Thin-film Transistors”.

∙ Junhyeong Park et al. " In-Ga-Zn-O Synaptic Transistor with 1 μm Channel Length for Neuromorphic Computing".

∙Chanjin Park et al., "Novel a-IGZO TFT Micro-LED Circuit with Improved Stability and Area Efficiency".

∙ Kyeong-Soo Kang et al., "A New Line-by-Line SWEEP Signal Generation Method for PWM Driving MicroLED TFT Pixel Circuit".

∙ Ji-Hwan Park et al., "New a-IGZO TFT Pixel Circuit for High-Resolution Mobile AMOLED Display for Good Optical Uniformity at Low Gray Levels".

The SID Student Branch at Seoul National University (SNU) is aimed to offer various programs including paper presentation, exhibition, and seminar.

∙ Officer

- Faculty advisor: Prof. Yongtaek Hong (E-mail: yongtaek@snu.ac.kr, Homepage: http://axel.snu.ac.kr)
- Chair: Ms. Sujin Jeong (audio0427@snu.ac.kr)
- Vice-Chair: Mr. Hyeon Cho (kebin1027@snu.ac.kr)
- Treasurer: Mr. Hanul Kim (withsk21@snu.ac.kr)
- Secretary: Mr. Jinsu Yoon (jsyun34@snu.ac.kr)

<Activities in 2022>

1. SID Display Week 2022: May 8 – 13, 2022, San Jose McEnery Convention Center, California, USA.

3 students presented their works at symposium as listed below:

∙ Jaeyoung Yoon et.al, “Reconfigurable and Reusable Soft Modular LED Blocks Assembly”.

∙ Jinsu Yoon et.al, “Highly Uniform Speckle Pattern Created Via an Elastomeric Stencil Mask for High-precision Digital Image Correlation Analysis of Substrate Stretching Deformation”.

∙ Jongho Park et.al, “Selective Coating CdSe/ZnS Quantum Dots on Stretchable Substrate with Controlled Density by Inducing Ligand Exchange Reaction”

2. Open-lab: June 21, 2022, Building 104-1, Seoul National University, Seoul, Korea

<Photographs of lab tour>

Our lab made an overall introduction of the research scope to the undergraduate students visited our lab.

3. GoGE/SDG Workshop 2022: August 19, 2022 (Online)

Our lab participated in GoGE/SDG Workshop on the topics of optics, photonics and electro-physics. Dongju Jang (Ph. D. candidate) gave a presentation, titled with “Sensitivity-enhanced, strain-engineered, stretchable strain sensors” in student’s session.

4. Seminar: August 19, 2022, Building 301, Seoul National University, Seoul, Korea

<Dr. Yeongjun Lee’s presentation>

Dr. Yeongjun Lee, who is currently working at Stanford university as postdoctoral scholar, presented the high-speed printing of nanoscale semiconductor materials and next-generation neuromorphic electronic devices.

5. IMID 2022: August 23-26, 2022, Bexco, Busan, Korea

5 students presented their works at symposium as listed below:

∙ Dongju Jang et al., “High-Performance, Stretchable Thermoelectric Generators with Reduced Internal Resistance for Practical Wearable Applications”.

∙ Hyunjun Yoo et al., “Light Stress Test of Flexible and Transparent Carbon Nanotube Thin-Film Transistors for Daylight Application”

∙ Hayun Kim et al., “Tailored Density Modulation of Carbon Nanotube Random Networks at the Channel for High-Performance Thin-Film Transistors”

∙ Jinsu Yoon et al., “Fabrication of Meniscus-free Stretchable Vertical Interconnect Access”

∙ Dong Keon Lee et al., “Cellulose/Carbon Black-based Flexible Pressure Sensor with High Linearity”

The SID Student Branch at Seoul National University (SNU) is aimed to offer various programs including paper presentation, exhibition, and seminar.

Officers
- Faculty advisor : Prof. Yongtaek Hong (E-mail: yongtaek@snu.ac.kr, Homepage: http://axel.snu.ac.kr)
- Chair : Ms. Sujin Jeong
- Vice-Chair : Mr. Hyeon Cho
- Treasurer : Mr. Hanul Kim
- Secretary : Mr. Jinsu Yoon

1. SID Display Week 2021: May 17 – 21, 2021, Online Conference

Student officers presented the laboratory’s emerging technologies at SID I-zone booth for the 10th anniversary.

<10th anniversary I-zone booth of AXEL>

2. IMID 2021: August 25 - 27, 2021, COEX, Seoul, Korea

2-1. SF-Zone exhibition

In SF-Zone, Daesik Kim, Jiseok Seo, Hanul Kim, and Donggen Lee demonstrated soft platform in front of participations as listed below;

∙ Real-time pressure mapping system using composite-based pressure sensor sheet

Highly sensitive piezoresistive pressure sensor could be demonstrated, enabling interactive visualization of the pressure distribution of a human palm and even small letters on a stamp in real-time. It is expected to be utilized in e-skin, HMI, or force/touch sensors for flexible displays.

 <Demonstration of pressure mapping system at SF-Zone exhibition>

2-2. Paper presentations

8 students presented their works at symposium as listed below:

∙ Dahyun Kim et al. “Inorganic Polysilazane-based Solution-processable Thin-film Encapsulation for Flexible Polymer Light-emitting Diodes”.

∙ Jiseok Seo et al. “Stretchable Pressure Sensor Using Conductive Silicone Elastomer Composite with Rigid Island Structure”.

∙ Hyunjoon Yoo et al. “Charge Trapping and Hysteresis Behavior in Carbon Nanotube Thin-Film Transistor with Ferroelectric Dielectric Layer”.

∙ Donggeon Lee et al. “Inkjet Printed Cellulose Nanofiber/Carbon Nanotube-based Flexible Pressure Sensor”.

∙ Dongju Jang et al. “Gold-welded silver nanowire network-based stretchable electrodes for wearable applications”.

∙ Sujin Jeong et al. “Enhancement of Adhesion and Reflectance of Silver Thin-film via Thiol-terminated Self-assembled Monolayer for Reliable Stretchable Electronics”.

∙ Geonhee Kim et al. “Precise Subtractive Patterning Method of AgNWs on Deformable Platform”.

∙ Jinsu Yoon et al. “Facile Adhesive Patterning of 3-D Curved PDMS for Various Human-interactive Sensors”.

The SID Student Branch at Seoul National University (SNU) is aimed to offer various programs including paper presentation, exhibition, and seminar.

Officers
- Faculty advisor : Prof. Yongtaek Hong (E-mail: yongtaek@snu.ac.kr, Homepage: http://axel.snu.ac.kr)
- Chair : Ms. Sujin Jeong
- Vice-Chair : Mr. Hyeon Cho
- Treasurer : Mr. Hanul Kim
- Secretary : Mr. Jinsu Yoon

1. IMID 2020: August 25 - 28, 2020, Online Conference

2 students presented their works at symposium as listed below:

∙ Seunghwan Lee et.al, “Electrohydrodynamic inkjet printed optical waveguide based on micro-pinning structures”.

∙ Geonhee Kim et.al, “Electrohydrodynamic inkjet printed micro-rigid-island arrays for application to stretchable platform”.

2. SID Display Week 2020: August 3 - 7, 2020, Online Conference

4 students presented their works at symposium as listed below:

∙ Hyeonggyu Kim et.al, “In-situ selective UV-O3 based facile patterning method of random SWCNT networks for solution-processed SWCNT TFT and circuit application”.

∙ Jaeyoung Yoon et.al, “Soft and reconfigurable wearable LED display using soft modular blocks”.

∙ Boik Park et.al, “Micrometer-scale patterning of self-assembled SWCNTs films and thin-film transistors using patterned PLL layer”

∙ Geonhee Kim et.al, “Micro-patternable AgNW-PEDOT:PSS hybrid electrodes for all-solution-processed polymer light-emitting diodes”

3. Invited seminar: May 1, 2020, Building 104-1, Seoul National University, Seoul, Korea

4 professors presented their works related to electrohydrodynamic (EHD) printing and its applications

∙ Presenter 1: Prof. Jae-Woo Joung

Jae-Woo Joung is professor at the Sungkyunkwan University. He introduced the manufacturing methods of inkjet printing head and discussed the future works for commercialization in various industries.

<Prog. Jae-Woo Joung's presentation>

∙ Presenter 2: Prof. Doyoung Byun

Doyoung Byun is professor at the Sungkyunkwan University and CEO of ENJET Corporation. He presented the concept of new EHD printing technology, named as the induced-EHD (iEHD), which can solve the electro-chemical reaction problem.

<Prof. Doyoung Byun's presentation>

∙ Presenter 3: Prof. Hyun Jae Kim

Hyun Jae Kim is professor at the Yonsei University. He presented the development of in-situ laser sintering, nozzle design, guide ring, and autofocusing techniques for EHD printing.

<Prof. Hyun Jae Kim's presentation>

∙ Presenter 4: Prof. Byung Doo Chin

Byoung Doo Chin is professor at the Dankook University. He introduced the recent progress of inkjet-printed devices including OLED and QLED. He also presented the important factors for fine printing in terms of the characteristics of ink such as viscosity, surface tension, and drying methods.

<Prof. Byung Doo Chin's presentation>

4. Invited seminar: February 20, 2020, Building 301, Seoul National University, Seoul, Korea

∙ Title: Structurally engineered nanocrystal quantum dots for light-emitting applications

∙ Presenter: Prof. Wan Ki Bae

Wan Ki Bae, who is currently assistant professor at the Sungkyunkwan University, presented recent achievements for high performance light-emitting diodes enabled by the structurally engineered QDs. In addition, he discuss the state-of-the-art of QD based optoelectronics applications and their potentials/limitations for practical realization.

 <Prof. Wan Ki Bae’s presentation (left) and SID student branch members at SNU (right)>

The SID Student Branch at Seoul National University​ (SNU) is aimed to offer various programs including paper presentation, exhibition, and seminar.

Officers
- Faculty advisor : Prof. Yongtaek Hong (E-mail: yongtaek@snu.ac.kr, Homepage: http://axel.snu.ac.kr)
- Chair : Mr. Seungwhan Lee
- Vice-Chair : Mr. Jaeyoung Yoon
- Treasurer : Mr. Deasik Kim
- Secretary : Mr. Hyeon Cho

1. Invited seminar: March 19, 2019, Building 104-1, Seoul National University, Seoul, Korea

∙ Title: Wireless electronics tattoos

∙ Presenter: Prof. Nanshu Lu

Nanshu Lu, who is currently temple foundation endowed associated professor at the University of Texas at Austin, is doing researches on the mechanics, materials, manufacturing and human integrations of soft electronics. In this seminar, a dry and freeform “cut-and-paste” method to fabricate wireless e-tattoos was introduced. She also explained about the concept of modular and reconfigurable e-tattoos.

2. SID Display Week 2019: May 12 - 17, 2019, San Jose McEnery Convention Center, California, USA

2-1. I-Zone exhibition

In I-Zone, Jaeyoung Yoon and Hayun Kim demonstrated two different skin-attachable devices in front of participations as listed below:

∙ Soft wearable LED display

∙ Soft wearable joint flexion monitoring system

These devices showed the feasibility of soft modular block assembly for “Do it yourself (DIY)” wearable, which enables to complete the customized wearable systems on the skin of each individual.

<Demonstration of DIY wearable devices at I-Zone exhibition>

2-2. Paper presentations

2 students presented their works at symposium as listed below:

∙ Seunghwan Lee et.al, “Printed reflective sloped wall for enhancing luminance of color-conversion light source”.

∙ Hyeonggyu Kim et.al, “Solution-processed single-walled carbon nanotube thin film transistor In-situ patterned by inkjet-printing of surface treatment materials”.

<Paper presentations at poster session of symposium>

3. IMID 2019: August 27 - 30, 2019, Hwabaek International Convention Center, Gyeongju, Korea

3-1. SF-Zone exhibition

In SF-Zone, Jaeyoung Yoon and Jiseok Seo demonstrated soft devices in front of participations as listed below:

∙ “Do it yourself (DIY)” wearable devices

∙ High-resolution pressure sensor array with real-time mapping system

The DIY wearable devices consist of soft modular electronic blocks with various functionalities. The customized wearable device can be achieved on the individual’s skin, enabling an accurate body signal processing.

With a magnetic field, Ni particles are vertically aligned in an elastomer, and conduction paths are formed. By simply attaching this soft electrodes at the top and bottom of the sensor array, high-resolution pressure sensor array over 100 dpi could be achieved.

<Demonstration of DIY wearable devices (left) and pressure sensor arrays (right) at SF-Zone exhibition>

3-2. Paper presentations

10 students presented their works at symposium as listed below:

∙ Hyeon Cho et.al, “Stretchable strain-tolerant soft printed circuit board: A systematic approach for design rules of stretchable interconnects” (KIDS gold award).

∙ Hyunuk Oh et.al, “All-solution-processed pressure-sensing active matrix PLED pixel” (Best poster award).

∙ Daesik Kim et.al, “Highly sensitive crack-based single-walled carbon nanotube strain sensor”.

∙ Hyunjun Yoo et.al, “Double-gate-structured carbon nanotube thin film transistors”.

∙ Jiseok Seo et.al, “A soft probe unit using conductive silicone elastomer composite for flexible electronic device inspection”.

∙ Geonhee Kim et.al, “All-solution-processed transparent polymer light-emitting diodes with transferred PEDOT:PSS electrodes”.

∙ Eunho Oh et.al, “Eutectic gallium-indium thermal VIA for heat dissipation on soft substrate”.

∙ Seunghwan Lee et.al, “Structural color generation from two-dimensional metallic nanostructures based on brushing assembly process”.

∙ Sujin Jeong et.al, “In-situ fabrication of wrinkled polymer light-emitting diodes on silicone rubber for applications in stretchable light-emitting devices”.

∙ Boik Park et.al, “Large-area assembly of aligned silver nano-wires conductors using parallel half-cylinder barrier by solution process”.

<Paper presentation at oral session (left) and SID student branch members at SNU (right)>

4. Invited seminar: December 13, 2019, Building 301, Seoul National University, Seoul, Korea

 ∙ Title: Polymer-assisted metal deposition for soft electronics

 ∙ Presenter: Prof. Zijian Zheng

Zijian Zheng, who is currently full professor at the Institute of Textile and Clothing (ITC) at the Hong Kong Polytechnic University, has been developed polymer-assisted metal deposition (PAMD) which allows ambient fabrication of flexible, stretchable, and wearable metal conductors with very high conductivity. He presented the fundamental chemistry and printing of PAMD, and its applications in soft electronic devices.

<Prof. Zijian Zheng’s presentation (left) and SID student branch members at SNU (right)>

5. Korea tech show 2019: December 13, 2019, Hall B, COEX, Seoul, Korea

In Korea tech show, Jaeyoung Yoon and Hanul Kim demonstrated soft devices in front of participations as listed below:

∙ “Do it yourself (DIY)” wearable devices

∙ High-resolution pressure sensor array with real-time mapping system

As well as the development of wearable devices, all of signal processing system implemented on a soft substrate.

<Demonstration of DIY wearable devices and pressure sensor arrays at Korea tech show>