-
-
News
News Highlights
- Books
Featured Books
- pcb007 Magazine
Latest Issues
Current IssueThe Hole Truth: Via Integrity in an HDI World
From the drilled hole to registration across multiple sequential lamination cycles, to the quality of your copper plating, via reliability in an HDI world is becoming an ever-greater challenge. This month we look at “The Hole Truth,” from creating the “perfect” via to how you can assure via quality and reliability, the first time, every time.
In Pursuit of Perfection: Defect Reduction
For bare PCB board fabrication, defect reduction is a critical aspect of a company's bottom line profitability. In this issue, we examine how imaging, etching, and plating processes can provide information and insight into reducing defects and increasing yields.
Voices of the Industry
We take the pulse of the PCB industry by sharing insights from leading fabricators and suppliers in this month's issue. We've gathered their thoughts on the new U.S. administration, spending, the war in Ukraine, and their most pressing needs. It’s an eye-opening and enlightening look behind the curtain.
- Articles
- Columns
- Links
- Media kit
||| MENU - pcb007 Magazine
Continuous Roll-process Technology for Transferring and Packaging Flexible Large-scale Integrated Circuits
September 2, 2016 | KAISTEstimated reading time: 1 minute

A research team led by Professor Keon Jae Lee from the Korea Advanced Institute of Science and Technology (KAIST) and by Dr. Jae-Hyun Kim from the Korea Institute of Machinery and Materials (KIMM) has jointly developed a continuous roll-processing technology that transfers and packages flexible large-scale integrated circuits (LSI), the key element in constructing the computer’s brain such as CPU, on plastics to realize flexible electronics.
Professor Lee previously demonstrated the silicon-based flexible LSIs using 0.18 CMOS (complementary metal-oxide semiconductor) process in 2013 (ACS Nano, “In Vivo Silicon-based Flexible Radio Frequency Integrated Circuits Monolithically Encapsulated with Biocompatible Liquid Crystal Polymers”) and presented the work in an invited talk of 2015 International Electron Device Meeting (IEDM), the world’s premier semiconductor forum.
Highly productive roll-processing is considered a core technology for accelerating the commercialization of wearable computers using flexible LSI. However, realizing it has been a difficult challenge not only from the roll-based manufacturing perspective but also for creating roll-based packaging for the interconnection of flexible LSI with flexible displays, batteries, and other peripheral devices.
To overcome these challenges, the research team started fabricating NAND flash memories on a silicon wafer using conventional semiconductor processes, and then removed a sacrificial wafer leaving a top hundreds-nanometer-thick circuit layer. Next, they simultaneously transferred and interconnected the ultrathin device on a flexible substrate through the continuous roll-packaging technology using anisotropic conductive film (ACF). The final silicon-based flexible NAND memory successfully demonstrated stable memory operations and interconnections even under severe bending conditions. This roll-based flexible LSI technology can be potentially utilized to produce flexible application processors (AP), high-density memories, and high-speed communication devices for mass manufacture.
Professor Lee said, “Highly productive roll-process was successfully applied to flexible LSIs to continuously transfer and interconnect them onto plastics. For example, we have confirmed the reliable operation of our flexible NAND memory at the circuit level by programming and reading letters in ASCII codes. Out results may open up new opportunities to integrate silicon-based flexible LSIs on plastics with the ACF packing for roll-based manufacturing.”
Dr. Kim added, “We employed the roll-to-plate ACF packaging, which showed outstanding bonding capability for continuous roll-based transfer and excellent flexibility of interconnecting core and peripheral devices. This can be a key process to the new era of flexible computers combining the already developed flexible displays and batteries.”
Suggested Items
2025 ASEAN IT Spending Growth Slows to 5.9% as AI-Powered IT Expansion Encounters Post-Boom Normalization
06/26/2025 | IDCAccording to the IDC Worldwide Black Book: Live Edition, IT spending across ASEAN is projected to grow by 5.9% in 2025 — down from a robust 15.0% in 2024.
DownStream Acquisition Fits Siemens’ ‘Left-Shift’ Model
06/26/2025 | Andy Shaughnessy, I-Connect007I recently spoke to DownStream Technologies founder Joe Clark about the company’s acquisition by Siemens. We were later joined by A.J. Incorvaia, Siemens’ senior VP of electronic board systems. Joe discussed how he, Rick Almeida, and Ken Tepper launched the company in the months after 9/11 and how the acquisition came about. A.J. provides some background on the acquisition and explains why the companies’ tools are complementary.
United Electronics Corporation Advances Manufacturing Capabilities with Schmoll MDI-ST Imaging Equipment
06/24/2025 | United Electronics CorporationUnited Electronics Corporation has successfully installed the advanced Schmoll MDI-ST (XL) imaging equipment at their advanced printed circuit board facility. This significant technology investment represents a continued commitment to delivering superior products and maintaining their position as an industry leader in precision PCB manufacturing.
Insulectro & Dupont Host Technology Symposium at Silicon Valley Technology Center June 25
06/22/2025 | InsulectroInsulectro, the largest distributor of materials for use in the manufacture of PCBs and printed electronics, and DuPont, a major manufacturer of flex laminates and chemistry, invite fabricators, OEMS, designers, and engineers to attend an Innovation Symposium – Unlock the Power - this Wednesday, June 25, at DuPont’s Silicon Valley Technology Center in Sunnyvale, CA.
OKI, NTT Innovative Devices Establish Mass Production Technology for High-Power Terahertz Devices by Heterogeneous Material Bonding
06/21/2025 | BUSINESS WIREOKI, in collaboration with NTT Innovative Devices Corporation, has established mass production technology for high-power terahertz devices using crystal film bonding (CFB) technology for heterogeneous material bonding to bond indium phosphide (InP)-based uni-traveling carrier photodiodes (UTC-PD) onto silicon carbide (SiC) with excellent heat dissipation characteristics for improved bonding yields.