Scintillation characteristics and imaging performance of CsI:Tl thin films for X-ray imaging applications

We have manufactured thallium-doped cesium iodide (CsI:Tl) scintillator thin films by the thermal deposition method. The scintillation characteristics of the CsI:Tl thin films were studied by X-ray-induced luminescence for different Tl doping concentrations between 0.05 and 1.0 mol%. The wavelength of the main emission peak was about 550 nm and the light intensity was increased and the emission peak shifted toward the long wavelength for higher Tl concentration in the X-ray luminescence case. X-ray diffraction (XRD) and scanning electron microscopy (SEM) for observation of structural properties was used to investigate the relationship between the microstructure affected by the evaporation condition and post-heat treatment, and the scintillation properties of samples. The imaging performance of the various CsI:Tl films fabricated will also be evaluated by an X-ray radiographic test after coupling to a CCD sensor.