Infrared pyroelectric detector and preparation method thereof

The invention discloses an infrared pyroelectric detector and a preparation method thereof. The detector comprises a wafer, the wafer comprises a silicon substrate, a dielectric film layer and a crystal layer which are sequentially arranged from bottom to top, two top metal electrodes are deposited on the surface of the crystal layer, an infrared absorption layer is deposited on at least one of the top metal electrodes, and the areas of the infrared absorption layers deposited on the two top metal electrodes are different; and a groove is etched in the back face of the wafer, the crystal layer is arranged at the bottom of the groove, and a bottom metal electrode is deposited on the crystal layer at the bottom of the groove. According to the infrared pyroelectric detector disclosed by the invention, the problem that the bottom metal electrode is difficult to lead out is solved by processing on the wafer, the thickness of the crystal layer is greatly reduced, and the detection rate of the infrared detector is i