Research On Adulteration Of SrTiO₃ Thick Film Sensor

Preparation techniques of Sol-Gel were researched in this dissertation and SrTi_0.8Mg_0.2O_2.8 was produced successfully. The polycrystalline oxide semiconductor Sr_1-xLa_x(Ti_1-yM_y)O_z was prepared by solid state synthesis reaction, the M includes Mg, Al, Fe and Cr and B was added in Simultaneously. Resistance-temperature properties and sensitivities of the samples in different temperature and oxygen partial pressures were investigated and explained properly.The samples were measured by SEM and XRD. XRD shows that the samples prepared by both Sol-Gel and solid state synthesis reaction are perovskite at different temperature. SEM shows that the powders prepared by Sol-Gel is smaller and consist of relatively homogeneous particles.The results show that substitution of Cr³⁺ at the Ti⁴⁺ site achieved P adulterate. Extrinsic oxygen vacancy can be produced and the exchange quantity of oxygen is increased between materials and ambient, hence it is possible to obtain SrTiO₃ exhibiting high oxygen sensitivity, the sensitivity has increased to nine. The hole concentration is increased as the valence transition between Cr³⁺ and Cr²⁺, and the conductivity is improved, the resistance is decreased to a few kilohms. The addition of B improves the attachment coefficient.