금속 산화물 기반의 완전 투명 히터

Abstract

In this study, a transparent heater based on metal oxides was developed. Although conventional heaters have been studied to improve transparency, their electrodes typically employ metallic materials that inherently possess opaque characteristics. To address this limitation, a functional electrode with an oxide/metal/oxide (OMO) structure was introduced for transparent electrodes to realize an all-transparent heater design. This structure maintained the excellent conductivity of silver (Ag) while achieving high transparency through indium-tin-oxide (ITO). The heating layer used ITO, similar to conventional transparent heaters, thereby maintaining an overall transparent structure. The ITO heating layer exhibited an excellent low sheet resistance of approximately 10 Ω/□, and the OMO electrode structure exhibited a low sheet resistance of approximately 2.5 Ω/□. Owing to this superior conductivity, the heater could reach a high heating temperature of approximately 220°C at an applied voltage of 7 V. In contrast to conventional Ag metal electrodes, this OMO electrode design implemented a multilayer structure combining Ag and ITO for the electrodes, satisfying the requirements of both transparency and conductivity. The multilayer structure was designed to maintain high transparency without compromising the performance, enabling the realization of transparent electrodes with excellent properties. The heater demonstrated an electrode transparency of approximately 67% and a heating layer transparency of 87%, significantly enhancing the overall transparency compared with conventional heaters. This transparent heater is expected to be applied in various next-generation transparent electronic devices such as smart windows and transparent displays.