Fabrication and Characterization of NiMn 2 O 4 NTC Thermistor Thick Films by Aerosol Deposition

Abstract Negative temperature coefficient (NTC) materials have been widely studied for industrial applications, such assensor, temperature compensation devices. NTC thermistor thick films of Ni 1+x Mn 2-x O 4+δ (x = 0.05, 0, −0.05) were fabricatedon glass substrate using the aerosol deposition method at room temperature. Resistance verse temperature (R-T) characteristicsof as-deposited films showed that B constant was ranged from 3900 to 4200 K between 25 o C and 85C without heat treatment.When the film was annealed at 600oC 1h, the resistivity of film gradually decreased due to crystallization and grain growth.The resistivity and the activation energy of films annealed at 600C for 1 h were 5.203, 5.95, 4.772 KΩ·cm and 351, 326,299 meV for Ni 0.95 Mn 2.05 O 4+δ , NiMn 2 O 4 and Ni 1.05 Mn 1.95 O 4+δ , respectively.Key wordsThermistor, Negative temperature coefficient (NTC), Aerosol deposition, Thick film. 1. 서 론 유비쿼터스 센서 네트워크, 지능형 자동차, 모바일 전자기기 등의 산업이 발전함에 따라 다양한 종류의 정밀한 센서가 요구되고 있다. 그 중 온도에 따라 재료의 저항이 변화하는 서미스터(thermistor)는 대표적인 온도 감지 센서로서 그 종류에는 NTC (Negative temperature coefficientof resistance)와 PTC (Positive temperature coefficient ofresistance)가 있다.