X-FAB: High-temp mission profile
September 19th, 2009 by Peggy Aycinena
Headquartered in Germany, X-FAB is a foundry with manufacturing operations in Erfurt and Dresden, Plymouth in the U.K., Lubbock in Texas, and Kuching, Sarawak in Malaysia. On September 8th, X-FAB made an interesting announcement with the introduction of their XA035 analog/mixed-signal CMOS high-temperature process for ICs that live tough lives: devices that operate in ambient temperatures of up to 175 degrees Celsius in places like the underside of your car.
I had a chance to speak this week by phone about the XA035 process with X-FAB Vice President of Business Development Mark Miller. Miller has a long and distinguished career in EDA with a track record that includes Business Development VP for DFM products at Cadence, VP at TeraSystems and at Synchronicity, and director of the IC Tech Center for Mentor Graphics. These days, Miller’s world is about manufacturing and that’s where our conversation started:
Mark said, “If you look around anyone’s living room, you’ll see a lot of electronics — high-definition TVs, computers, gaming stations, and so on. Our XA035 process, however, is targeted at something different. Of course, the process can be used for ‘standard’ ICs, and for non-volatile memory, [but it also addresses] a wide voltage range that extends beyond the usual digital foundry [offering].
“XA035 is focused on what we call the ‘hidden’ semiconductor markets. Extremely important, these markets include automotive, avionics, and military applications, all of which have as a key attribute the ability to meet stringent qualifications. Interestingly, it’s automotive reliability that involves a lot of such hot and harsh environments, even more so [than some other markets].
“If you’re building a control system in a car, for instance, the electronics have to withstand the underside of a car, where temperatures can go as high as 175 to 185 degrees C. That’s [also the case with] your braking system, another application area where reliability is critical. Just think of a designer being able to use a process technology like XA035, one that meets [industry standard specifications such as] AEC-Q100].
“But, there’s even more in our announcement. If you’re a designer, you also want to be able to analyze your design inside of its [target] environment, along with temperature-qualified models. You want to be able to cycle things 10,000 times or more, to look for dielectric breakdown and stress migration. That requires a lot of extended modeling. Yes, it can be expensive, but if you’re a designer for chips under the hood, you have no choice. Today’s [automotive standards] are not just a list of features, they also include a set of tests and reliability requirement. Most major auto manufacturer [understand this], especially in developing mission critical features.
“It’s outside of [the usual foundry business model] to offer analysis tools, but we have put together a reliability simulator and modeling tool that will take your particular design, establish a mission profile, and then go through and model it for you. The tool [allows you] to understand what the lifetime reliability parameters are, which is a really interesting and novel approach.
“Some products degrade in a step-function failure mode, while others may [exhibit] a gradual decline over a 20-year period. The designers can see all of that with our tools, and therefore understand how to tweak the design to meet the parametric degradation [predicted by the simulation].
“High reliability electronics is a very special applications area. Something a designer develops might be used [in a system] for the next 20 years. As a result, [we see] the designer’s paradox. If you have the responsibility for designing such a product, how do you model it? How many times will it be used. What is the mission profile? With our tools, the designer can take the specifications, and all the models, to get a very clear picture of the reliability. The tool interfaces directly to the device specification and characterizing — it’s pretty unique.”
I asked Mark if analog and mixed-signal devices are more susceptible than digital devices to degradation when deployed in harsh environment.
He said, “It turns out that [in general], the variety of devices manufactured in an analog/mixed-signal foundry is substantially different from what you make in a standard digital-type foundry. We’re not just talking about 3 to 5 volts here. Some of these analog/mixed-signal products [endure] up to 500 or 600 volts. Extensive modeling of those devices [during development] is critical.
“Analog and mixed signal have always been a great deal more work than standard digital. It’s the analog/mixed-signal product that has to interface with the real world. That kind of development requires pretty rigorous engineering and process development.”
I asked Mark if X-FAB headquartered in Germany because of the automotive industry centered there. Mark, who works out of Silicon Valley, said, “Our offering, and the XA035 process in particular, is not specifically an automotive application. In addition to Germany, we also have manufacturing in Malaysia and Texas. X-FAB is very much a global presence, but a lot of the history of the company is centered in Germany.
“There are other independent foundries in the world, but we’ve been in the business for longer than anybody else in analog, mixed-signal [domain]. Working in the general area of high reliability is not new for us.
“The XA035 [really speaks to all of that]: the overall high reliability of devices built on the process, the wide variety of device sizes available including non-volatile memory, and the tools for degradation modeling and developing a mission profile.”
Mark concluded, “There’s a lot of artistry, and creative, innovative design that [characterizes] the analog domain. At X-FAB, we feel that we are very much in that tradition and contributing to its growth.”
The Press Release …
X-FAB Silicon Foundries announced XA035, an analog/mixed-signal CMOS high-temperature foundry process for ICs requiring operating temperatures up to 175 degrees Celsius. The modular 0.35 micrometer process is the first to enable high-temperature-capable SoCs, combining high-voltage and embedded non-volatile memory elements.
Design support includes the XA035 Lifetime Calculator, a tool that calculates expected IC lifetime for a given mission profile to help determine lifetime/temperature trade-offs.
The new XA035 high-temperature process surpasses the stringent AEC-Q100 qualification tests for automotive IC quality and reliability, and is ideally suited for high-precision analog circuits, sensor front-ends, and brushless DC motor controls for automotive, industrial, aerospace and military markets.
X-FAB offers XA035 design kits covering all major EDA platforms. It also features a variety of dense standard cell libraries optimized for area, speed, low power or low noise; and I/O libraries, including ESD support. All libraries take the temperature effects into account. In addition, XA035 supports parasitic diode modeling. This new feature enables pre-layout parasitic diode leakage simulation and lets designers simulate leakages at high temperatures early in the design flow.