Preparation and photo-induced properties of lead lanthanum zirconate titanate multilayers

Abstract

This paper reports on the formation of multilayer structures and the highly improved photo-induced output current of the lead lanthanum zirconate titanate (PLZT) employed. The photo-induced effect of ferroelectrics has the advantage of simple mechanisms of non-bias applications, which are indispensable for semiconductor p-n junctions. But the output current of PLZT bulk is too low for it to be used as a device current source. The new design is described using an upper transparent indium tin oxide electrode. The PLZT film structure exhibited an output current of the order of microamperes upon light illumination. The photo-induced current of the PLZT film was more than 102 times that of bulk PLZT. These differences are due to the characteristics of the design of the multilayers including the configuration of the electrode. The PLZT film also has the advantage of easy output control and suitability for use on Si. A simple model is used for an illustratative explanation of the improved photo-induced effect in the PLZT film. Results show that the photo-induced effect of the ferroelectric multilayer is useful as the current source for micro-electro-mechanical systems.

Hyper-sensitive piezophotovoltaic effects in ferroelectric nanocylinders

“…Recent experimental and theoretical works have established that among all known perovskite ferroelectric materials, ͑Pb 0.97 La 0.03 ͒ ϫ͑Zr 0.5 Ti 0.5 O 3 ͒ ͑PLZT͒, or BFO could be the most promising candidates for photoelectric applications. [16][17][18][19][20][21][22][23][24] Photovoltaic effects occur generally in systems with asymmetric interfaces, such as semiconducting p-n junctions or metal-semiconductor interfaces with Schottky barriers. [1][2][3][24][25][26] Both experimental and theoretical works have shown that the FPV effect is different from that in conventional p-n junctions or Schottky barriers of the semiconductors.…”

“…[1][2][3][24][25][26] Both experimental and theoretical works have shown that the FPV effect is different from that in conventional p-n junctions or Schottky barriers of the semiconductors. [18][19][20][21][22][23][24][25][26][27] Although a complete understanding of the physical mechanisms involved in the FPV effect in metal-ferroelectric-metal ͑MFM͒ structures with the shortcircuit boundary conditions has not yet been accomplished, a widely accepted explanation of the photoelectric current is the separation of the photon-generated electron-hole pairs ͑excitons͒ by the internal electric field, [20][21][22][23][24] which also provides the potential difference that drives the photocurrent in the external circuit connected to the ferroelectrics. In absence of an external electric field, the internal electric field comes from the depolarization field produced by polarization screening charges in the metal electrodes and the inhomogeneous polarization distribution near interfaces.…”

“…41,42 It is clear that FPV effects may become very small when the average internal electric field in FNC is zero. [16][17][18][19][20][21][22][23][24] In this case, the photocurrent is only due to charge transport via diffusion.…”

Modelling and experiments of PLZT/PVDF hybrid drive method for non-contact shape adjustment

“…In 2000, Poosanaas et al explained the mechanism of PLZT anomalous photovoltaic effect using a voltage source model, and verified it by experiments [18]. In 2004, Ichiki et al studied an output current improving scheme based on PLZT multilayers, and made the output current 100 times higher than previously reported result [19].…”

Modeling of wireless remote shape control for beams using nonlinear photostrictive actuators

“…Although the PLZT's response speed to light irradiation has been improved dramatically by optimizing ceramic composition and dopant type in the last five years, the response of bulk material is not fast enough to be used in vibration control of structures so far (Ichiki et al, 2004). Therefore, the focus of this research will be on the quasi-static or static shape control of structures using photostrictive material.…”