Effects of RF magnetron sputtering power density on NTC characteristics of Mn-Co-Ni thin films

摘要

Thin film NTCR (negative temperature coefficient resistance), based on Mn-Co-Ni oxide, was prepared by reactive RF magnetron sputtering with various sputtering power density (0.95-3.82 W/cm~2). The crystalline structure and surface morphology of the NTC thin film were analyzed by XRD and AFM. The NTC characteristics, as a function of sputtering power density, were investigated. The values of B, α_(25) and R_(25) were in the range of 3,740-3,847 K, -4.328 to -4.207 %/K and 8.7-2,082.5 KΩ, respectively. With the increasing power density, the standard resistance (R_(25)) decreased and the consistency of R_(25) increased. Thin film NTCR with stable B value (3,740 K), low R_(25) (104 Ω) and excellent consistency could be fabricated in mass production with about 3.82 W/cm~2 sputtering power density.