Abstract: Ba_xSr_1-xTiO₃（BST） thin films were prepared by sol-gel method, and the differential dielectric constant against temperature is improved up to 6% around 11℃ by the introduction of a buffer layer. The detector pixel patterns and microbridge were fabricated by lift-off and chemically etching methods after semiconductor lithographic process. Photograph results show that the fabrication of UFPA detector pixel is well resolved. A detector circuit were also designed, and the Protel simulation shows that it can provide appropriate signal for later process.