Pyroelectric detectors based on high-performance PMN-PT single crystals

摘要

Single crystal of Pb(Mg~(1/3)Nb~(2/3))O_3-PbTiO_3 (PMN-PT), as one of the best pyroelectric materials, wasrnfirst discovered by Chinese scientist. In this paper, PMN-PT was selected as pyroelectric detectorrnmaterial. Firstly, an electrically calibrated pyroelectric detector with special structure was developed forrncalibration of radiation. The sensitive area of the detector is 10mm×10mm and the entrance aperturernis Φ8mm. The research about the coating film on the surface of the sensitive area was carried out.rnCarbon nanotubes (CNTs) were selected as the coating material. The responsivity of the detector isrnabout 18.3 V/W at 14 Hz. The detectors were used to establish an electrically calibrated system withrnuncertainty less than 4% at room temperature. The relative deviation of measurement is less than 3 %rnbetween 0.2 W/m~2 and 200 W/m~2, and the relative deviation is less than 5 % between 0.002 W/m~2 andrn0.02 W/m~2. Secondly, a 128×1 linear array was designed and fabricated. The responsivity of the linearrnarray is 3.5×10~4 V/W at 10 Hz, and the noise equivalent radiant power (NEP) is 0.4 nW. Thernpyroelectric array and CMOS read-out circuit were electrically bonded by ultrasonic bonding processrnto be uncooled focal plane array (FPA). The FPA was tested under different radiation intensity. Thesernresults lay a foundation for the development of high-performance uncooled pyroelectric FPA based onrnnovel ferroelectric single crystals.