A new oxygen sensor with PN junction of silicon as the substrate is fabricated.The operation principle

structure design

process and characteristics analysis of the sensor are described.Ag electrodes and TiO

2

thin films are prepared by RF magnetron sputtering process.The microstructure and surface morphology are examined by X-ray diffractometer（XRD） and scanning electron microscopy（SEM）

and the oxygen-sensitive mechanism of TiO

2

thin films is discussed.Experiments results show that this kind of sensor has the characteristic of small volume

low power and good linear degreed.