Akoustis Technologies, a pre-revenue start-up pursuing single crystal bulk acoustic wave (BAW) filters for mobile devices, reported that the company has fabricated a single crystal BAW filter for the 2.7 GHz band. In a release, Akoustis said this is the world's first single crystal BAW filter.

The MMIC BAW filter, approximately 1 sq mm in die area, had less than 1.0 dB insertion loss in the 2.7 GHz passband, with "high" isolation and fractional bandwidths "consistent with the piezoelectric material composition in the resonator." The measured bandpass results agreed with simulations from the company's BAW resonator circuit models. To successfully develop the filter, Akoustis made several process enhancements, including band-specific resonator tuning for multi-pole ladder network filter configurations.

Jeff Shealy, CEO of Akoustis, said, “Through the process advancements reported today, Akoustis has leveraged its vertical IP portfolio to successfully extend our technical capabilities from developing single crystal resonators in a R&D capacity to producing integrated BAW RF filter die that will serve as the basis of our product offerings.”

Akoustis claims their single crystal piezoelectric material will provide better performance than current BAW filters. The company aims to be a pure-play supplier of high-band (4G/LTE/LTE-A) BAW filters, which the company sees as greater than a $2 billion market opportunity.

According to the company's release, Akoustis is focusing on:

• expanding its process capabilities to deliver high quality factor (Q) resonators,
• developing materials that deliver high K-squared resonator bandwidth, and
• designing and fabricating filter prototypes to support engagements with potential design clients and strategic partners.