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Integration of thin-film oxide piezoelectrics on glass is imperative for the next generation of transparent electronics to attain sensing and actuating functions. However, their crystallization temperature (above 650 °C) is incompatible with most glasses. We developed a flash lamp process for the growth of piezoelectric lead zirconate titanate films. The process enables crystallization on various types of glasses in a few seconds only. The functional properties of these films are comparable to the films processed with standard rapid thermal annealing at 700 °C. A surface haptic device was fabricated with a 1 μm-thick film (piezoelectric e33,f of −5 C m−2). Its ultrasonic surface deflection reached 1.5 μm at 60 V, sufficient for its use in surface rendering applications. This flash lamp annealing process is compatible with large glass sheets and roll-to-roll processing and has the potential to significantly expand the applications of piezoelectric devices on glass. Direct growth of piezoelectric oxides on glass is difficult due to high processing temperatures. Here, the authors demonstrate a flash lamp process for the growth of films on various glasses in a few seconds only. The films have piezoelectric e33,f of −5 C m−2 and can be used in haptic devices. [ABSTRACT FROM AUTHOR]

Emerging haptic technology based on piezoelectric actuators enables to realize innovative tactile human–machine interface. The standard solution is based on stand-alone bulk ceramics glued directly on the haptic device. Thin-film actuators with metal–insulator–metal structure have been developed to directly integrate actuators on haptic plates. The thickness of thin films is limited to 2 μm, leading to large capacitance and, thus, too high-power consumption. To solve this issue, we developed haptic devices based on a 10 μm-thick PZT film deposited on a 0.65 mm-thick platinized silicon substrate. These thick films are made of a PZT composite slurry associated with sol-gel sol infiltration. They are dense and exhibit a permittivity of 1000 and dielectric loss lower than 0.05. Our fabricated haptic device containing three actuators connected in series exhibits an antisymmetric Lamb wave resonant mode at 62.0 kHz, in line with finite element modeling. At the limit of touch detection (1 μm out of plane deflection), the power consumption of the haptic device is 150 mW at 40 V. This represents a 15-fold consumption reduction with respect to the same haptic device made with 0.5 μm-thick PZT thin films. [ABSTRACT FROM AUTHOR]

Transparent thin‐film piezoelectric transducers are attractive for haptic displays. However, for their widespread use in consumer electronics, innovative and cost‐effective processing methods need to be developed. In this contribution the effectiveness of the deposition of lead zirconate titanate thin films by inkjet printing for the fabrication of haptic devices is demonstrated. The 1,3‐propanediol solvent is used to prepare effective inkjet‐printing inks from chemical solution deposition solutions. The printed thin‐film structures on fused silica glass substrates are 900 nm thick and strongly {100} oriented perovskite phase is detected in X‐ray diffraction patterns. To fabricate devices, interdigitated capacitors and SU‐8 insulation layers are deposited on top of the printed lead zirconate titanate. Dimensions of the final device are 15.7 × 3.4 mm2. A standing antisymmetric Lamb wave is observed at 63.3 kHz, with out‐of‐plane displacement reaching 2 µm at an applied voltage of 100 V. This value exceeds the limit at which the texture rendering function can be induced in the device. Good functional performance of the device is linked with good electromechanical properties of the printed piezoelectric, with permittivity ε ′ and piezoelectric coefficient e33,f values of 1000 and 7.7 C m−2, respectively, which are comparable to films prepared by standard spin‐coating process. [ABSTRACT FROM AUTHOR]

Surface haptic devices based on piezoelectric actuators are one of the most promising solutions to achieve subtle touch feedback on various surfaces. In comparison to stand-alone actuators, piezoelectric thick film actuators not only have a low power consumption and a large deflection range, but also allow for direct integration on various substrates. Herein, we fabricated power-efficient haptic actuators by screen-printing 10 µm-thick platinum bottom electrode and 80 µm-thick niobium-doped lead zirconate titanate (PZT) on alumina substrate (25.5 ×12.5 mm2). Our fabricated haptic device containing two actuators (10 ×1 mm2 per actuator) connected in parallel exhibits an antisymmetric Lamb wave resonant mode at 17.8 kHz, in line with finite element modelling. At the limit of touch detection (1 µm out of plane deflection), the device consumes only 5 mW at a unipolar voltage of 20 V pp. At a unipolar voltage of 150 V pp , the peak-to-peak out-of-plane displacement reaches nearly 10 µm. [Display omitted] • Screen printed 80 µm niobium-doped PZT on alumina substrate creates a piezoelectric haptic device inducing a 17.8 kHz Lamb wave resonant mode. • Low power haptic effect: 1µm deflection needs 20V, using 5mW power- 20x less than closest state of the art, allowing tactile feedback. • At 150 V the deflection reaches 9.5 µm. [ABSTRACT FROM AUTHOR]