SmartphoneRF switches use SOI wafers as the default substrate, says Soitec

July 15, 2013 // By Jean-Pierre Joosting
Soitec has announced that its silicon-on-insulator (SOI) technologies are now "mainstream" for manufacturing switches and antenna-tuners, key RF components used in all cell phones and tablet computers.

According to the industry research firm Yole Développement, more than 65% of substrates used in fabricating switches for handsets are SOI based, showing the massive adoption of RF SOI for this market experiencing double-digit growth. Chip manufacturers are relying on SOI technology to offer the best price/performance ratio and enable next-generation smartphones.

Soitec provides the engineered substrates - wafers - at the heart of RF integrated circuits, enabling chip manufacturers to integrate various functions on the same die, bringing down the overall system cost. An RF SOI substrate features an active layer on which CMOS transistors are built, isolated from a high-resistivity silicon base layer. This reduces noise and interference, helping the finished die reach its target performance in terms of signal integrity, handling RF power and integration density. SOI technologies enable devices to reach a figure of merit for on-series resistance and off-equivalent capacitance (Ron.Coff ) below 200 fsec with potential for further reduction. This directly relates to improved device performance and smaller die size.

Another driver of SOI's growth is the evolution towards more performance required for updating wireless networks from 3G to 4G/LTE and further LTE Advanced using carrier aggregation. SOI technologies exceed stringent linearity requirements such as intermodulation distortion (IMD) far beyond -110 dBm, helping to avoid interference with other networks.

"RF SOI technologies enable the device integration, cost effectiveness and high performance needed for high-volume 3G and LTE applications, " said Bernard Aspar, vice president, Communication & Power Business Unit at Soitec. " RF, with over 100% revenue growth last year, remains a strategic market in which we have been continuously investing for more than a decade. Soitec is the leading supplier of engineered wafers and we are continuing to pioneer strong innovations with our partners to catch the next wave of grow th in the RF market."