Thin thermistor films of Mn1.56 Co(0.96-x)Ni0.48CuxO4 with spinel structure were prepared on amorphous A12O3 substrate by chemical solution deposition method at a temperature of 750 ℃ in air, which is much lower than the traditional sintered temperature of 1100 ℃. The X-ray diffraction indicates that with the increase copper content, the preferred direction of crystalline is different under the same growth condition, but these films keep spinel structure well with increased crystallinity. The calculation of the grain size for all films have been performed by using the Scherrer' s equation, and we found that the grain size increased with the increase of the content of Cu. Scanning electron microscope (SEM) analysis showed that their surfaces were smooth and dense, free from cracks. The values of characteristic temperature T0, activation energy E and NTC(Negative Temperature Coefficient) α(295K) for Mn1.56Co(0.96-x)Cux04 films were obtained from their electrical properties. The result revealed that a lower Cu component corresponded to a higher value of a. Increasing Cu constituent,α decreased from -4. 12% to -3. 29%. The extinction coefficients of this films were determined by spectroscopic ellipsometry(SE) and their extinction coefficient peaks were identified. Key words; X-ray diffraction; scanning electron microscope (SEM) characteristic temperature T0; activation energy E; spectroscopic ellipsometry(SE); extinction coefficient%用化学溶液沉积法,以Al2O3为衬底在750℃温度下制备了锰钴镍铜Mn1.56 Co(0.96_x) Ni0.48 CuxO4系列薄膜.制备温度低于传统烧结工艺需要的温度(1100℃).采用X射线衍射(XRD)对所制备材料的结晶性能进行测量.结果表明,在一定范围内随着铜组分的增加,材料的择优取向发生变化,结晶性能提高且保持立方尖晶石单相结构.根据Scherrer方程和XRD数据计算薄膜的晶粒尺寸,Cu含量的增加导致薄膜晶粒尺寸增大.扫描电镜(SEM)图验证了制备的薄膜材料均匀致密,无裂痕.测量材料的变温I-V特性,计算材料在295 K下负温度电阻系数α及其活化能和特征温度,当Cu含量低时材料的α值较大,随着Cu组分的增加,α由-4.12％下降到-3.29％.利用椭偏光谱仪(SE),拟合材料在近紫外-可见-近红外波段的消光系数,并初步指认消光系数峰.
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