MACOM Announces STMicroelectronics as GaN on Si Manufacturing Partner

Updated on 7 February to add information disclosed during MACOM's earnings call on 6 Feb 2018.

MACOM and STMicroelectronics (ST) are teamed to commercialize MACOM’s RF GaN on Si technology, with ST becoming a second source and adding capacity to MACOM’s GaN fab in Lowell, Massachusetts. ST will run RF GaN on Si wafers in its 6-in power electronics fab in Catania, Italy, expanding to ST’s 8-in fab when volume warrants.

A formal agreement between the two companies gives MACOM exclusive rights to use its technology for mobile phone, wireless base station and commercial telecommunications infrastructure applications. MACOM has granted ST a license to use the technology for RF power applications, such as solid-state cooking, automotive spark plugs and industrial lighting, which are complementary to ST’s power electronics business.

In a call with Microwave Journal, MACOM CEO John Croteau said the two companies have been working together for more than two years. MACOM’s GaN on Si process couldn’t simply be transferred to ST; it had to be adapted to be compatible with ST’s CMOS platform, then qualified. MACOM’s process uses gold metallization for bond pads, while ST’s process only uses aluminum. Croteau said ST has replicated MACOM’s process, achieving equivalent or better RF performance and reliability.

Sample production from ST will begin this year (2018), although that won’t pace MACOM’s initial production programs for base stations. Croteau said these programs have been qualified with devices from the Lowell process, and the Lowell fab has the capacity to support program volumes.

MACOM sought a manufacturing partner for GaN on Si to establish high-volume manufacturing capacity and dramatically reduce the cost to displace LDMOS in base station power amplifiers. Croteau said GaN on Si running on 6-in wafers achieves more than 90 percent of the benefits MACOM is seeking.

The agreement with ST also gives MACOM access to ST’s high volume assembly and test capabilities in Malta.

In a release announcing the agreement, Croteau said, “MACOM has refined and proven the merits of GaN on Si using rather modest compound semiconductor factories, replicating and even exceeding the RF performance and reliability of expensive GaN on SiC alternative technology. We expect this collaboration with ST to bring those GaN innovations to bear in a silicon supply chain that can ultimately service the most demanding customers and applications.”

Marco Monti, president of the automotive and discrete product group at STMicroelectronics, said, “While expanding the opportunities for existing RF applications is appealing, we’re even more excited about using GaN on Si in new RF energy applications, especially in automotive applications, such as plasma ignition for more efficient combustion in conventional engines, and in RF lighting applications, for more efficient and longer-lasting lighting systems.”

According to Eric Higham, longtime industry analyst at Strategy Analytics, reducing power amplifier cost to $0.04/W is viewed as the threshold for high-volume RF energy applications. “Potential RF energy device shipments could be in the hundreds of millions for applications including commercial microwave cooking, automotive lighting and ignition and plasma lighting, with sales reaching into the billions of dollars,” he said.

Earnings Call Color

During MACOM’s earnings call, held shortly after the company announced the agreement with ST, Croteau spoke about the importance of the agreement, saying “Our collaboration with ST is expected to have the scale, cost structure and frontend wafer supply chain which we believe will uniquely position MACOM to become a top-tier supplier servicing the roughly $1 billion market for 4G LTE power amplifiers.”

He added that ST will give MACOM the cost structure and capacity to produce the next generation of infrastructure power amplifiers for massive MIMO arrays.

Listen to his comments:

During the question-and-answer portion of the call, Tore Svanberg, a financial analyst with Stifel Nicolaus, asked whether the deal with ST is influenced by MACOM’s lawsuit against Infineon concerning GaN on Si IP. Croteau responded that a court ruling on 29 January affirmed MACOM’s rights, including the right to sublicense the technology to ST.

Listen to the exchange: