On the investigation of the electro-optical sensor potential of Boswellia serrata resin

In a first step, Boswellia serrata (Bs) resin was purchased in its natural state and dissolved in deionized water and coated on the n-Si wafer by spin coating method as a thin film with about 1 mu m. SEM images and EDX analyses of Bs resin film on the n-Si wafer were obtained. It has been seen that the fabricated Bs/n-Si device has an unsymmetrical current-voltage (I-V) graph and a good rectifier feature. Then, we analyzed some electrical characteristics of Bs/n-Silicon heterojunction. Using light intensity-dependent (in the range of 100-250 mW/cm2) current-voltage (I-V) and in dark, capacitance-conductance-voltage (C-G-V) and capacitance-frequency (C-f) measurements of Bs/n-Si heterojunction were investigated. The heterojunction shows a photodiode behavior such that the reverse-bias photocurrent exceeds the dark reverse current and the reverse bias current increased linearly with increasing light intensity. Hence, we determined the sensitivity, responsivity, detectivity and main rectifying junction parameters such as rectifying ratio, ideality factor, barrier height, and series resistance. Furthermore, the barrier heights from the reverse bias C-V measurements were determined and it was found to depend on the frequency. In forward biases, the C decreased with increasing frequency while G increased. In summary, it was concluded that Bs forming a p-n heterostructure with n-Si is a potential material for optoelectronic applications.