At its 70,000-square-foot Microelectronics Center (MEC) in Nashua, N.H., BAE Systems develops and produces GaAs- and GaN-based compound semiconductor materials, devices, circuits, modules and subsystems at frequencies from below 1 to 200 GHz. The MEC supplies compound semiconductor ICs and modules to a variety of internal and external customers and has been a Department of Defense Category 1A Trusted Supplier since 2008. In addition to advanced device research and development, the company fabricates devices in production quantities for DoD programs, inserting its technology into fielded products. For example, BAE Systems delivered nearly 1 million GaAs MMICs to support F-22 production.
The MEC’s advanced 100 kV e-beam lithography capability defines critical features as small as 20 nm, enabling highly repeatable definition of larger gate features. The facility uses MBE technology to precisely grow high quality PHEMT and MHEMT active device layers on GaAs substrates. GaN-on-SiC wafers grown by MOCVD are obtained from carefully-qualified suppliers. The MEC’s 6-inch wafer processing line has been running production GaAs MESFET and PHEMT processes since 2004, and the company installed a facility for high rate manufacturing of high power GaN modules in 2015.
In 2016, the company consolidated microwave hardware development and production into the MEC, from material growth and wafer processing to IC and module design, test and manufacturing. This greatly enhanced the ability to design for manufacturability and affordability.
The foundry’s current 4-inch GaN-on-SiC production processes leverage the enhanced uniformity and automation of its 6-inch equipment. Six-inch GaN wafer processes have recently been demonstrated with high yield, equivalent performance and excellent reliability, with an MTTF of more than 107 hours at 200°C channel temperature. Release to production is planned for August 2017. Producing GaN MMICs on 6-inch wafers addresses one of the last remaining challenges to making this new technology affordable.