Gamma Radiation Monitoring Through Thin Film of ClAlPc Doped With TiO{sub 2}

Chloroaluminum phthalocyanine (ClAlPc) synthesized by adopting focused microwave synthesis approach was doped with nanocrystalline TiO{sub 2} (5% by weight) and developed into the thin film sandwiched device having ITO/ClAlPc:TiO{sub 2}/Ag Schottky configuration by spin coating technique covering 1 cm{sup 2} as an active area. The so fabricated device having initial dark current of the order of 0.2 5 m A was exposed to variable dose of gamma radiation ranging from lcGy to 10 Gy at a dose rate of 1 Gy/hour. The experimental observation reveals the generation of localized traps leading to structural disorder within the solid material. Doping with TiO{sub 2} enhances the surface area of the film which in tern improves sensitivity of device to wider dose rage. Exposure of the device to variable dose of gamma radiation imparts decrease in forward bias current and capacitance characteristics with increase in radiation dose. Also, absorbance characteristics of the Al Pc: TiO{sub 2} was analyzed before and after exposure to radiation which reveals that absorbance decreases with radiation dose leading to decrease in optical band gap.