Wavelength Dependent Anisotropic Photo Sensing Activity of Zirconium Trisulfide Crystal
Abstract According to the performance requirements, either bulk or nanocrystalline form of the material can be used for different types of device applications. In the present study, zirconium triselenide bulk crystals were grown by direct vapour transport technique. The as-grown crystals and powder have been examined under Carl Zeiss optical microscope and scanning electron microscope for morphological studies which revealed the evolution of crystalline phases of the material by the layered kind of growth mechanism. The energy dispersive analysis of X-ray (EDAX) characterization confirms that no impurity is found in the resulting product except the desired material. To study the effect of different wavelength sources (Blue-470 nm, Green-540 nm, Red-670 nm) on bulk zirconium trisulfide photodetectors, pulsed photo response experiment was carried out. The anisotropic behaviour is also revealed using the same sources. Various device parameters like responsivity, sensitivity, detectivity and external quantum efficiency (EQE%) were calculated. The highest responsivity and detectivity of 81.7 µA/W and 3.56 × 1007 Jones were achieved for blue (470 nm) light source respectively.