Fabrication and Electro-Mechanical Characteristics of Piezoelectric Micro Bending Actuators on Silicon Substrates

Abstract

Fabrication and the electro-mechanical characteristics of fourteen types of piezoelectric micro bending actuators PMBA on silicon substrates using sol-gel multi-coated, thick PZT Pb Zr 0.52 , Ti 0.48 O 3 films and MEMS processes were investigated. A PMBA was a piezoelectric body adhered to an elastic body. If an electrical field is applied to the z-axis, the piezoelectric body expands along the z-axis while contracting along the x-and y-axes. The elastic body was therefore deflected due to the generated bending moment. It was thought that PMBA might be used for designs of micro-fluidic devices and micro transducers. PMBA were fabricated using 2 mm-thick PZT films on Pt 350 nm SiO 2 500 nm Si 300 mm substrates with a MEMS process. Fourteen types of PMBA were fabricated with different sizes of silicon diaphragms, PZT films and top electrodes. When sizes of silicon diaphragms, PZT films, and Pt top electrodes with 3000 mm by 1389 mm, 4000 mm by 1000 mm, and 4000 mm by 980 mm were reduced down to 3000 mm by 194 mm, 4000 mm by 140 mm, and 4000 mm by 120 mm, respectively, the center displacements of PMBA were decreased from 0.70 mm to 0.13 mm at 5 Hz and 12 V pp . At 5 V pp and 10 kHz, in case of Sample 1 of Group 4, the center displacements were maintained in the range of 0.50 mm-0.56 mm up to 1.25 G cycles without remarkable degradation.

A Feasibility Study of a Novel Piezo MEMS Tweezer for Soft Materials Characterization

“…Furthermore the piezoelectric materials can be manufactured using the same MEMS conventional technologies and for this reason these materials have been preferred to develop piezo-MEMS devices in the last decades. Typical applications include vibration energy harvesters [65,66], resonators [67], capacitors [68], micro sensors/actuators [69,70], micromachined ultrasonic transducer [71], gyroscopic sensors [72], microlens [73,74], 1D and 2D micro-scanners [75,76].…”

Ferroelectric Properties and Domain Structures of (Bi_0.5K_0.5)TiO₃-BiFeO₃ Ceramics

“…Lead-based perovskite ferroelectric materials represented by lead zirconate titanate (PZT) have been widely used for various kinds of electronic devices such as actuators, sensors, ultrasonic transducers, and many other applications because of their excellent piezoelectric properties [1][2][3][4]. However, the toxicity of lead is recognized as a serious problem, and the use of lead-containing materials in electronic devices is legally restricted among European Union by the Restriction of Hazardous Substances Directive (RoHS), except for the cases in which the use of lead-based materials is unavoidable, such as PZT for fabricating piezoelectric devices.…”

“…Bismuth ferrite (BiFeO 3 : BFO) has attracted considerable attention because of its high Curie temperature (T C ) of 830 °C, large spontaneous polarization (P s ) exceeding 100 C/cm 2 , and multiferroic properties [5][6][7][8][9]. It is expected that BFO-based solid solutions exhibit a higher depolarization temperature (T d ) than that for the other materials.…”

Microstructures Related to Ferroelectric Properties in (Bi0.5K0.5)TiO3–BiFeO3

“…Ferroelectric materials based on solid solutions of perovskite-structured oxides, such as lead zirconate titanate [Pb(Zr 1Àx Ti x )O 3 (PZT)], have been widely utilized for actuators and sensors because of their excellent piezoelectric properties. [1][2][3][4][5][6] On the other hand, materials containing poisonous substances, such as lead (Pb), are legally restricted in electric devices. This restriction requires us to develop new lead-free ferroelectric materials.…”