Preparation and Photovoltaic Properties of a Sintered CdS/CdTe Thin Film Light Sensor

Abstract

The sintered CdS/CdTe thin-film photovoltaic cells have been prepared on borosilicate glass substrates by successively repeating screen printing and sintering. The preparation conditions of the sintered CdS/CdTe cell for a visible-light-radiation sensor were investigated. The sintering condition of CdTe film has a strong influence on the electrical and the optical properties of the CdS/CdTe junction. The optimum sintering condition of CdTe on the as-sintered US film with less 0.1wt% of CdCl₂ was 600-620°C for 60 minutes.
The sintered CdS/CdTe photovoltaic cells show a spectral response of the quantum efficiency nearly constant in the range of 530 to 850nm. The temperature coefficient of short-circuit current density is almost constant in the range of -50 to 70°C. The temperature coefficient of open-circuit voltage is about -1.85mV/°C. The cell shows a linear dependence of short-circuit current density on light intensity over the whole measurement range. A photosensitivity under a white fluorescent lamp and a response time of the cell are about 0.7nA/mm²⋅lx and about 3μs respectively. These values of the CdS/CdTe cells are comparable to those of a typical single crystal silicon p-n photodiode. The sintered CdS/CdTe photovoltaic cell can be used as a visible-light-radiation sensor.