The Korea Institute of Machinery and Materials (KIMM), under the Ministry of Science and ICT (President Park Sang-jin), has developed the world's first mass manufacturing technology for chemical adsorption nano-transfer-based nano-photonic devices that do not require adhesive. This is expected to dramatically improve the production process of expensive nano-photonic devices used in various fields, ranging from nano-photodetectors to nano-LEDs and nano-solar cells, thereby increasing economic efficiency.

The Korea Institute of Machinery and Materials (KIMM) announced on the 17th that Director General of the Strategic Coordination Division, Jung Jun-ho, developed an adhesive-free chemical adsorption nanotransfer technology and published the research results in the 16th issue of 'ACS NANO,' a prominent journal in the field of nanotechnology. This research was conducted in collaboration with the research team of Professor Moon-Ho Kim from the Department of Electrical and Electronic Engineering at Nanyang Technological University (NTU) in Singapore.

This study succeeded in developing a chemo-adsorption nanotransfer technology capable of mass-producing high aspect ratio nanostructure-based nanophotonic devices at a low cost. It has been successful to mass-produce high-performance nano-optical devices using only low-cost nano-transfer equipment and wet etching equipment instead of existing high-cost lithography equipment and dry etching equipment.

The chemisorption nanotransfer process developed in this study utilizes the chemisorption phenomenon that occurs when a 20 nm thick layer of gold is deposited on a flexible nanostamp patterned with nanostructures and pressure is applied to a substrate under specific pressure (5 bar) and temperature conditions (160-200℃). When chemisorption occurs, an adhesive force is formed between the gold thin film and the substrate, causing the gold thin film of the nanostamp to be transferred to the substrate.

Until now, expensive dry etching processes were required due to the adhesive between the structure and the substrate, but by utilizing the developed technology, an economical wet etching process called Metal-Assisted Chemical Etching (MAC etch) is possible. The MAC etch process is a wet chemical etching process using a metal catalyst such as gold, in which the substrate is etched through an oxidation-reduction reaction between the substrate immersed in the etching solution and the metal catalyst.

Professor Moon-Ho Kim of Nanyang Technological University (NTU) in Singapore stated, “We fabricated large-area, uniform micro-semiconductor structures on the entire surface of a wafer at low cost,” adding, “We succeeded in securing core technology that enables the uniform production of a large number of devices while minimizing defects.”

"This research achievement is the result of synergy created through international joint research based on the strengths of both institutions, such as KIMM's nano-transfer technology and Nanyang Technological University (NTU)'s wet etching technology," said Jung Joon-ho, Head of the Strategic Coordination Division. "We plan to develop mass manufacturing technologies for nano-LEDs, nano-solar cells, and next-generation batteries through follow-up research."

Meanwhile, this research was supported by the 'Extreme Material Property System Manufacturing Platform Technology' project of the Wave Energy Extreme Control Research Group under the Ministry of Science and ICT.