The partial substitution of sulphate (SO<sub>4</sub><sup>2-</sup>) by phosphate (PO<sub>4</sub><sup>3-</sup>) in triglycine sulfate (TGS) single crystal can improve the properties of the TGS family crystal as room temperature infrared (IR) detector. Phosphoric acid (H<sub>3</sub>PO<sub>4</sub>)-doped triglycine sulfate (TGSP) single crystal has strong pyroelectric properties due to its high pyroelectric coefficient and reasonably low dielectric constant. This family of single crystals can grow easily and rapidly and are reasonably good uniform detectors in the electromagnetic region from UV to IR at room temperature and without using cryogenic cooling.
TGSP single crystals were grown by saturated solution method. In order to investigate the detection sensitivity of the TGSP crystal, single crystals with different dopant concentration of phosphate (PO<sub>4</sub><sup>3-</sup>) ion were grown. A rather complete back-scattering Raman scattering spectra and hysteresis loops of the grown crystals were recorded and compared with each other. The Raman spectra and their assignments only will be reported here.