NXP opened a new GaN fab in Arizona to focus primarily on the communications infrastructure market for 5G radio systems, but looking ahead to 6G...
NXP opened its own new 150mm (6-inch) GaN fab built in Arizona to focus primarily on the communications infrastructure market for 5G radio systems and with technology migration to future 6G in mind.
In an interview with EE Times, Paul Hart, executive VP and GM at NXP, pointed out that in-house capacity was vital to address the growth in the RF market for telecoms. “Supply security is one reason to have our own fab, as well as the need to be able to evolve the technology faster for GaN over the next decade. To run at the pace we want in this market, we wanted to have ownership of that technology. For us to be successful in the market, we had to differentiate.”
The new 150mm factory supports the expansion of advanced communications infrastructure in the industrial, aerospace and defense markets. Hart also explained that the new facility has all the most advanced quality control systems which are connected to the same silicon fab on the same campus.
The opening ceremony featured speeches and comments from NXP’s executives and federal, state and local government officials. During the opening keynote, NXP’s CEO pointed out that this marks the beginning of a new era for NXP as an integral part of GaN technology for the future of 5G.
NXP’s new GaN fab, based in Chandler, is now qualified with a whole range of products that are coming to market and expected to reach full capacity by the end of 2020. Hart said that NXP had invested around $100 million over the last three years, and it was a retrofit of an existing site. “The fab was in use for some end of line functions. Because of its locale and the fact that many GaN experts within NXP were already based in Chandler, Arizona, we could leverage existing capabilities already in place there.”
GaN features for 5G
With 5G, the density of RF solutions required has increased exponentially. That makes it imperative to reduce energy consumption. GaN power transistors have emerged as the holy grail as they are able to offer the best performance.
NXP has optimized its GaN technology to improve electron entrapment in the semiconductor, so as to ensure high linearity and low memory effects.
The new structure allows NXP to keep an eye on the future of technology with the growth of frequencies at stake not only with 5G but also with the future 6G telecommunications. The idea behind this is the same as in Motorola, says Hart, “Where we started to invest about 20 years ago, first in device physics, device engineering, and then in the process engineering elements needed to create or manufacture these rather complicated structures.”
Over the years, NXP has perfected its technology by offering new GaN solutions starting in 2014. Subsequently, with the proprietary process achieved in 2016, this allowed for a closer match between technology development and product development so that “we could play on the advancement of state-of-the-art at a fairly fast pace”.
Hart added, “This is also how we have approached this RF power market sector over the past two decades. We have been market leaders in this sector since the mid-1990s with LDMOS silicon solutions as our technology of choice. And with this technology, we have evolved every 18-24 months with a new node, a new generation, leading to greater efficiency, better linearity, better performance. And it was really a closely coupled journey between systems engineering, product engineering and device technology so that our products were really aligned with the ever-evolving communications industry. And that’s how we want to approach GaN development in the future, which is why we made this great investment with a new factory.”
The new GaN fab’s flagship products are RF power amplifiers for 5G radio infrastructure that require a MIMO antenna coverage solution with 32 or 64 elements in a phased array radar configuration, along with more traditional higher power lower antenna order solutions.
“Most deployments will target at 3.5 gigahertz, which is a wide global frequency range for 5G, as well as the lower frequency ranges in more traditional communications bands like 1.8 and 2.1 GHz. This is what we are doing today with silicon products, we also have GaN products in that space we have produced through foundry partners. This fab will help us to continue the roadmap of products towards greater efficiency in these frequency spaces because the general trend we see on the market today is a push towards more power,” Hart said.
“The 5G radios support much higher bandwidth to allow higher data rates, higher bandwidth, and high antenna diversity. Power is important if we want to maintain the same coverage at higher bandwidth and the goal is to increase the transmitted power without increasing the size or weight of the radios at the top of the tower.”
“In order to be able to increase efficiency and continue to push in power, it is necessary to use GaN, as its’ properties make the process possible, thus providing a good reason for investment.”
“As for the fab, we are producing gallium nitride pHEMTS’s on silicon carbide. We are focusing on silicon carbide substrates because we think it gives the highest efficiency and best thermal management for gallium nitride. The process node is at 150mm which is very advanced, with the same quality systems we use in all other NXP factories. Most of the GaN on SiC production is at 100mm,” said Hart.
He added, “In our production flow, we have established three or four test points during the production process to monitor both standard semiconductor parameters along with specialty testing to monitor memory effect levels. The structure of the material, the lattice structure of gallium nitride on the silicon carbide, is obviously not as uniform as silicon and can create these memory effects which can significantly degrade performance in communications systems. Therefore we have created a number of unique in-line tests to monitor these behaviors and ensure we are creating the highest quality GaN for 5G.”
“We have about 10 new products that will be released by the end of this year and we expect the fab to be at full capacity by early 2021. If we can successfully implement our roadmap, we will allow our customers to significantly reduce the size of their boxes, radios, weight, cost. As the cost and size decrease, it becomes economically more viable to see wider global deployments of 5G; beginning first in denser urban to suburban areas and later including wider area coverage solutions,” Hart commented.
NXP’s strategic move to build an in-house GaN fab was driven by a desire to more tightly couple technology innovation with radio system performance leveraging their core experience in cellular infrastructure developed over the past 25 years. The factory will serve as a hub of innovation that will facilitate collaboration between the fab and NXP’s on-site R&D team. NXP’s engineers can now develop, validate and protect inventions more quickly for current and future generations of GaN devices, reducing cycle times and increasing the pace of future innovations.
Hart emphasized that the company has the scalability in mind. “Technology migration from 5G to 6G will happen over the next 8-10 years. The GaN technology and toolset is built with that frequency migration in mind, presently from 3.5GHz to 15GHz. We have a GaN plan for this.”