A domestic research team has developed a new technology that implements semiconductor devices on hair‑thin optical fibers. It is expected to provide a new breakthrough for the development of "wearable computers," a future dream product.

The research team led by Professor Tae‑Wook Kim at Jeonbuk National University (JBNU)'s Graduate School of Flexible Printed Electronics announced on the 20th that it has developed a "highly integrated electronic‑fiber technology" that can serve as a core platform for next‑generation wearable electronic devices.

The research results were published as a paper titled "Integration of multiple electronic components on a microfibre towards an emerging electronic textile platform" in the online edition of Nature Communications (IF: 14.919) on June 8. The paper was also selected as an Editors' Highlight, a designation by the journal's editors for particularly noteworthy articles, reflecting worldwide academic interest in this research.
* Editors Highlights page (https://www.nature.com/ncomms/editorshighlights)

The study involved research teams from the KIST Jeonbuk Branch, Pusan National University, Chonnam National University, Seoul National University and Korea University, and was conducted under the National Research Foundation of Korea's mid‑career researcher support program.

Conventional semiconductors are fabricated on flat substrates (wafers) and therefore lack flexibility, limiting their use in wearable computers that can be integrated into clothing. Recent foundational research on wearable computer fabrication has focused on approaches such as making thin flexible substrates that attach to garments as patches, or weaving metal fibers with semiconductor fibers to create electronic fibers.

However, these technologies often lack integration with garments, which can cause discomfort for the wearer. When fibers are woven to make electronic textiles, high‑density integration is not achievable, preventing the manufacture of high‑performance semiconductors. This is why the development of a new electronic‑fiber platform technology is required.

To address this, Professor Tae‑Wook Kim's team used an optical fiber core with hair‑like thickness (diameter 150 microns) as a substrate and fabricated semiconductor devices on its surface. To apply semiconductor processes to the hair‑like fiber substrate, they used a coating method that exploits capillary action to deposit a photoresist (a light‑sensitive polymer material used for semiconductor patterning), called capillary Tube Assisted Coating (CTAC). They successfully implemented transistors, inverters, ring oscillators, a UV sensor and temperature sensors on a 10 cm length of fiber surface.

They applied these fibers to garments and confirmed that they exhibit high performance together with what they describe as the highest electronic‑fiber integration density currently available. The research team reported that the devices operated stably and normally under various bending states, temperature conditions and external UV exposure, as well as before and after washing and when in contact with sweat.

Compared with conventional electronic fibers produced by weaving semiconductor fibers and electrode fibers, this technology integrates semiconductor devices directly onto the fiber surface. In terms of integration density and performance, it represents a fundamentally different electronic‑fiber platform from previously reported electronic fibers.

Moreover, if applied to infinitely long fibers, the process could enable continuous manufacturing—unlike conventional wafer‑based semiconductor fabrication—making it a potential game changer that could alter the existing paradigm for producing wearable semiconductors.

If dedicated electronic‑fiber manufacturing processes are further developed, it would be possible to implement Intel's Pentium CPU, released 20 years ago, in a 19.3‑centimeter electronic fiber. This demonstrates the vast potential of the technology as a core technology for future fiber‑based computers.

Professor Tae‑Wook Kim said, "Unlike existing electronic fibers, this new electronic‑fiber platform technology applies current semiconductor processes to create semiconductor devices on hair‑thin fiber surfaces, enabling the development of highly integrated, high‑performance electronic fibers. By applying this technology, it will be possible to produce new‑concept, high‑performance electronic fibers in a continuous process—much like drawing thread in a textile mill."