From FeRAM to Integrated Passive Devices (IPDs): will MEMS applications be the driver for future growth of thin film PZT?
The most promising effect of thin film PZT for future aplications would certainly be its piezoelectric effect
In September 2013, EPSON has announced its next generation inkjet technology, PrecisionCore, introducing for the first time MEMS inkjet heads manufactured with thin film PZT technology. This announcement has been highly publicized: First, thin film PZT MEMS applications are now on the market, proving the reliability and maturity of this technology! Second, more inkjet head players will soon follow.
Thin film piezoelectric materials are gaining increasingly more importance within the MEMS industry. Although semiconductor manufacturing companies are historically reluctant to introduce such exotic materials into their production lines, every major MEMS foundry nowadays is working on the implementation and qualification
of piezoelectric thin film in their MEMS manufacturing processes.
Lead zirconium titanate or PZT (Pb[ZrxTi1-x]O3 with 0≤x≤1)) is a very interesting ferroelectric material. Depending on its composition, it has the advantage of combining 3 different material properties: high dielectric constant, pyroelectric effect and piezoelectric effect.
Its high dielectric constant property is still extensively being used with the integration of thin film PZT in Integrated Passives Devices (IPDs) and to a lesser extent in Ferroelectric memories (FeRAM). These have been the 2 leading applications for thin film PZT for many years. NXP Semiconductors and STMicroelectronics dominate this IPD market.
The pyroelectric effect of PZT is today being used by Pyreos for thin film PZT based uncooled Infrared detectors, although this thin film PZT based technology remains quite marginal in this field.
The most promising effect of PZT for future applications would certainly be its piezoelectric effect.
Companies like Wavelens and PoLight are extensively working on the introduction of their autofocus based products to the market using thin film PZT technology. This profusion of new MEMS applications using thin film PZT technology is just beginning.
The roadmap for high volume production is still to be built
The main difficulty for thin film PZT technology is the integration of this exotic material into a robust and reproducible process flow. There are major technological challenges associated with thin film PZT integration into a product :
These are complex topics and although many R&D efforts have been made so far by labs, equipment and material suppliers, and device manufacturers, some work remains to be done to achieve robust products for high volume production.
More information on that report at http://www.i-micronews.com/reports/Thin-Film-PZT-Semiconductor-Trends-Update/1/404/