Ultraviolet sensor of non-bias type; layered film structure of photovoltaic ferroelectrics

This paper reports on the formation of layered film structures and the highly improved photoinduced output current of the lead lanthanum zirconate titanate (PLZT) employed. The photovoltaic effect of ferroelectrics has the advantage of its simple mechanisms of non-bias applications which are indispensable for semiconductor p-n junctions. The new design is described using an upper transparent indium tin oxide (ITO) electrode. The photovoltaic current of the PLZT film was more than 10 times than that of bulk PLZT. The PLZT film also has the advantage of easy output control and suitability for use on Si. Results show that the photovoltaic effect of the ferroelectric layered film is useful as the current source for micro-electro-mechanical systems (MEMS).