Piezoelectric, SAW Wafers and Crystals

A Piezoelectric Crystal is a crystal material that exhibits the positive piezoelectric effect and the inverse of the piezoelectric effect. This means piezoelectric crystals can generate an electric charge or redistribution of charge centers corresponding to an exerted mechanical stress or deformation, and the amount of charge transferred is proportional to the magnitude of the mechanical strains. The piezoelectric effect is reversible, therefore in the converse situation, when a piezo crystal is subjected to an electric field, there will be mechanical deformation along a certain direction occurring inside the crystal. The piezoelectric properties of the piezoelectric crystals, in essence, arise from the asymmetric arrangement of atoms in the crystal lattice, allowing small displacements or rearrangements/rotations of the electric dipoles. In the case of stress-induced electrical effect, when stress is applied, changes in the crystal structure alter the positions of electric dipoles, redistributing charge centers and generating electrical charges. In the case of field-induced mechanical effect: when an electric field is applied, the realignment of electric dipoles causes the crystal to deform, resulting in mechanical strains.

The applications of piezoelectric crystals are wide, including piezoelectric sensors/filters/resonators, harvester and actuator, sonar detection, ultrasonic transducers for medical imaging, SAW filters and SAW sensors, etc. Compared to that of the bulk ceramics, the electromechanical conversion properties of the base crystal cells are better. Since the piezoelectric effects were first discovered in crystals such as quartz and tourmaline by French scientist Curie's brother in 1880, scientists developed manifolds of new piezoelectric crystals in succession, such as Quartz (SiO2), Lithium Niobate (LiNbO3), Lithium Tantalate (LiTaO3), Lead Magnesium Niobate-Lead Titanate (PMN-PT, or PMNT), and more.

Piezoelectric crystals are often used in Surface Acoustic Wave (SAW) Devices. A Surface Acoustic Wave (SAW) device is a device that transfers the input electrical signal into an acoustic (mechanical) signal through the piezoelectric effects, The acoustic wave propagates along the surface of the piezoelectric SAW grade substrates or wafer, and in the end, the acoustic signal will be transferred into electrical signal at the other terminal of the substrates. This is achieved using Interdigital Transducers (IDTs), which are comb-like electrodes patterned on the surface of a piezoelectric material. Types and applications of SAW devices including SAW filters for telecommucations, SAW resonators in oscillator circuits, Saw delay lines in radar systems and signal synchronization. SAW devices serve essential roles with the advantages of processing signals of high frequencies, compact sizes, low power consumption, and high sensitivities.

Hangzhou Shalom EO is a specialized supplier providing Piezoelectric Crystals, Wafers, and Substrates or Surface Acoustic Wave (SAW) Grade Crystals Wafers, and Substrates in both off-the-shelf and custom versions. Shalom EO offers a series of top-class piezoelectric crystals and SAW grade crystals and wafers/substrates at competitive prices, our product portfolio includes Quartz, LiNbO3, LiTaO3, LGS, PMN-PT, PIN-PMN-PT in the form of crystal ingots/boules, substrates/wafer blanks, and polished substrates/wafers with dimensions up to 6 inches in diameter. Special shapes can be customized and electrodes can be coated. From crystal growth and fabricating, and machining, to inspection, Hangzhou Shalom EO observes each stage with care and ensures that our customers receive a premium product at an excellent value with our professional knowledge.

Quartz excels with high thermal stability and a high-quality factor which makes it excellent for high-frequency oscillators and filters even with a low electromechanical coupling coefficient; LiNbO3 has a great electromechanical coupling coefficient but its negative temperature coefficient is large; LiTaO3 has an advantage over LiNbO3 in terms of temperature coefficient but its electromechanical coupling coefficient does not even reach a quarter of LiNbO3’s. With leading-edge craftsmanship, Shalom EO also presents our PMN-PT (or PMNT) and PIN-PMN-PT crystals and crystals substrates, which are novel piezo crystal materials for the next generation of electromechanical transducers, we offer PMN-PT and PIN-PMN-PT with superior bandwidth, output power, and optimized piezoelectric sensities.