Eco-friendly semiconductor free of toxic 'lead'... Hanyang University breaks through limits in performance and lifespan

[Financial News] South Korean researchers have developed next-generation eco-friendly semiconductor technology that, without using lead, which is harmful to humans, enables faster charge transport than existing technology and a lifespan of at least 16 years.
A joint research team led by Professor Park Hee-jun of Hanyang University's Department of Organic and Nano Engineering and Professor Kim Gyeong-hak of its Department of Chemical Engineering said on the 5th that it had developed a molecular design technology that greatly improves the performance and long-term stability of eco-friendly perovskite semiconductors using tin instead of lead. The research findings were published in the international journal Science Advances.
The semiconductor industry has long looked to perovskite materials, which efficiently control light and electrons, as a next-generation semiconductor. However, existing materials contain lead, a toxic substance, limiting their commercialization as eco-friendly electronic devices. Tin was studied as an alternative to lead, but it has a critical weakness: it oxidizes easily in air and develops defects, causing its performance to deteriorate quickly.
The research team addressed this problem by introducing a chemical molecular-design technique that precisely controls ionic interactions within the crystal, using guanidinium thiocyanate. This suppressed defects inside the semiconductor and greatly enhanced the stability of its crystal structure.
As a result, the newly developed eco-friendly transistor achieved world-leading levels in switching speed and efficiency among existing tin-based semiconductors.
In particular, the team dramatically improved what had been the technology's greatest weakness: long-term reliability. The semiconductor maintained stable performance after being switched on and off at least 12,000 times, or after exposure to air for at least 100 days. Accelerated lifetime tests conducted at room temperature showed that it could retain at least 70% of its initial performance for approximately 16 years.
Professor Park Hee-jun said, "This study demonstrates that the unstable structure of tin-based semiconductors can be overcome through precise design at the molecular level, going beyond simply controlling defects," adding, "We expect this approach to be broadly applied in various advanced industries, including next-generation displays, optical sensors, and low-power logic circuits."  

[email protected] Kim Man-gi Reporter