We successfully fabricated the high-performance transparent thin film heaters using ITO/AgPd/ITO laminated films with various thickness combinations and investigated their optical, electrical, structural and heating properties in detail. The surface temperature rise rate (TRR) from 0 to 7 seconds for the ITO (200 nm)/AgPd (10 nm)/ITO (200 nm) under the applied voltage of 6.0 V was 16℃/s, where the temperature reached over 300℃ within 20 sec. The transmittance at 550 nm of this heater was 81%, where the sheet resistance was 4.2 Ω/□. The cross-sectional HREM analyses revealed that the bottom and top ITO films showed quite different polycrystalline structures after the temperature rising tests, which can be explained by the solid-phase and vapor-phase crystallizations, respectively.
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