Integrated pyroelectric detector arrays with the sensor material PVDF

Abstract

Integrated PVDF pyroelectric radiation detectors have been made, using a simple technique to interface the pyroelectric material with the silicon substrate. The silicon substrates incorporate the electronics for a 8x1 array and a 2x2 array. The relevant sensor parameters voltage responsivity, detectivity and the thermal crosstalk are measured within a frequency range from 0.01 Hz to 5000 Hz. With the 400 μm thick silicon substrate the voltage responsivity is typically 100 V/W, the maximum detectivity is 7×10⁶ cm□Hz/W at a frequency of 30 Hz. An improvement of both voltage responsivity and detectivity is possible by reducing the heat loss to the silicon substrate. This can be realized by a reduction of the substrate thickness, at least underneath the detector area. A further improvement is possible by a reduction of the capacity of the electronic circuit on the silicon chip and by the use of ferroelectric materials with higher pyroelectric coefficients, for example TGS.