News and New Products

Piezoelectric substrates are temperature-compensated

By Gabe Moretti -- EDN, 11/13/2003

Piezoelectric materials can convert electrical signals into sound waves that can propagate along the materials surface or through its bulk. Conversely, sound waves or mechanical vibrations on the surface or in the bulk of the material can convert into electrical signals. You can use piezoelectric crystals for converting electrical signals into sound waves. You use the crystals to build structures that resonate within narrowly defined frequency ranges. These structures are well-suited for highly selective filters in wireless-communication systems. However, heating and cooling effects during operation of these devices affect their performance. To address that problem, Ziptronix has announced temperature-compensated piezoelectric substrates to improve component performance for a range of wireless-communication and consumer-electronic devices.

To overcome the thermal limitations of certain piezoelectric materials, the company combined low-cost piezoelectric materials, such as lithium tantalate and lithium niobate, with glass, quartz, or other materials that offer a low CTE (coefficient of thermal expansion). The resulting material offers the functions of the piezoelectric material and minimize the unfavorable effect from the high CTE of the piezoelectric material alone.

The new substrates enable cost-effective technologies, such as surface-acoustic-wave filters, to serve applications designers previously implemented with higher cost alternatives. Ziptronix is currently making the substrates available for sampling. Prices for evaluation lots of as many as 10 bonded-wafer pairs begin at about $13,000; shipping is usually two to three weeks after receipt of order. Volume prices vary based on the type of material and the size of the order.

Ziptronix, 1-919-459-2400, www.ziptronix.com.