Select

Piezoelectric Material Technologies

Technology Overview

A number of materials are known to exhibit the piezoelectric effect, which is the generation of electricity when the material undergoes mechanical stresses. Ferroelectric ceramics, such as lead ziroconium titanate (PZT) are commonly exploited for their piezoelectric properties. Piezoelectric devices have been made in the form of bulk piezoelectrics ceramics or as deposited films on a substrate.

There are certain challenges faced by the current industry, particulary in the processing conditions of such materials. These limit their widespread application and often lead to high costs. The challenges include high processing temperature for ceramic sintering, poor performance in piezoelectric thick film, and environmental concerns on the lead-based materials.

This series of technologies, know-how and in-house capabilities aim to address these concerns.

Technology Features & Specifications

The technologies and capabiltiies include:

1. Method of producing piezoelectric thick film starting from ceramic material to the deposition on substrate surface by screen printing process

  • Piezoelectric thick film potentially has larger actuating forces and larger sensing signals
  • Thickness of a thick film range between 10 - 100um
  • Lower annealing temperature between 800 - 1000 deg.C
  • Overcome the technical challenges relating to processing and integration compatibility with the underlying substrate
  • Improveed mixing homonogeneity in the distribution of the metal oxide powder throughout the PZT powder in the as-deposited film
  • Improve uniform distribution of the glass bonding phase in the piezoelectric ceramic material
  • More reliable piezoelectric performance

 

2. New ceramic composition of complex oxides that can be sintered at a lower temperatures of  800 - 900 deg C and at the same time exhibit excellent piezoelectric properties by using columbite synthesis route. Oxides of valence 2 metal elements is used to promote sintering and perovskite phase formation

  • Enable use of high silver alloy as internal electrode material to replace precious metals such as Pd and Pt
  • Improve the material and processing compatibilities for integrating piezoelectric ceramic thick film
  • Maintain excellent piezoelectric properties, demonstrated d33 of 151-393 pC/N

 

3. Method of producing lead-free metal-oxide piezoelectric thin films KNN which possess large effective piezoelectric coefficient comparable to lead-based piezoelectric thin film PZT. The preparation method involves chemical solution approach with the introduction of appropriate chelating agents in the KNN precursor solutions.

  • KNN films with similar piezoelectric performance of the un-doped KNN bulk ceramics: 90-120pm/V
  • Comparable effective d33 for PZT piezoelectric films under similar substrate constraint 70-130pm/V
  • Improved in current leakage - one order of magnitude lower than the smallest leakage current reported
  • Broad operation temperature range, up to 420 deg.C

Potential Applications

There are a variety of widespread applications for piezoelectric materials:

  • Piezoelectric ceramic materials for various piezoelectric sensor, actuator, transducer applications
  • High dielectric constant (high K) materials for capacitor applications

Customer Benefits

We are looking for industry partners:

  • To be collaborator to further develop the technology for specific applications
  • To license the technologies for self development and/or integratration into product

Make an Enquiry