Fe^(3+)对钛酸锶稀薄燃烧氧敏薄膜电阻的影响

Effect of Fe^(3+) addition on resistance of SrTiO_3 thin film as oxygen sensor

利用溶胶-凝胶的方法制备钛酸锶氧敏薄膜,掺杂不同含量的铁离子,并测试了不同氧分压、温度下薄膜的电阻。发现铁离子的含量在20mol%～25mol%之间时,掺杂对钛酸锶电阻的降低有明显的影响,含铁在20%和25%的钛酸锶在600～800℃之间电阻的变化趋近为零,铁的含量大于25%或小于20%薄膜没有出现这种现象。

The SrTiO3 thin film used as oxygen sensor was prepared by Sol- gel method. The Fe ion content in Fe- doped SrTiO3 thin film is 10mol% , 15mol% , 20mol% , 25mol% , 30mol% , respec- tively. All samples were measured in the temperature range of 600℃ - 800℃ and PO2 region from 0 to 0.25× 105Pa.The results show that the thin film exhibit P- type conduction. It is found that when the Fe ion content is between 20mol% to 25mol% ,the resistance of SrTiO3 fells obviously and it is independent on temperature from 600℃ to 800℃ .The results can be explained according to the defect chemistry equations.