Experimental characterization of triglycine sulfate as a radio-frequency radiation detector

The use of pyroelectric detectors for the detection of amplitude-modulated RF radiation is considered. The family of pyroelectric materials includes triglycine sulfate. Triglycine sulfate (TGS), chemical structure (NH₂CH₂COOH)₃-H₂SO₄ , was selected for the study partly because it is nontoxic, it does not require exotic equipment to grow a usable crystal, and the crystal is easily manipulated into the desired shape. A crystal of 4-5 cm (maximum dimension) with an acceptably low number of defects/occlusions can be grown in four weeks under less than pristine conditions. TGS is water soluble, which makes it easily cut and shaped. Another factor in the selection of TGS is the ability to easily determine the ferroelectric axis for initial cleaving of the crystal. To investigate electrical performance potential at frequencies between 0.1 and 20 GHz, prototype pyroelectric detectors were fabricated, and some of their characteristics were experimentally determined in the 3-6-GHz band. The results demonstrate that the detection of free-space radiation using the pyroelectric effect in TGS is practical in certain applications