MRAM Hopeful Tweaks Game Plan Under New CEO

　　Spin Transfer Technologies (STT), one of a handful of startups developing MRAM technology, has tweaked its strategy under the leadership of former Maxim and Spansion executive Tom Sparkman, who took the helm of the company in July.

　　STT (Fremont, Calif.) is still developing what it calls orthogonal spin transfer MRAM featuring perpendicular magnetic tunnel junctions (pMTJs) and continues to sample MRAM devices to potential customers in North America and Asia. But in addition to working to offer functional MRAM memories, STT is now planning to productize what it calls an MRAM engine to be embedded in a spin torque transfer MRAM array to correct for inherent flaws in the MTJ technology and boost the performance of MRAM.

　　In his first interview with EE Times since taking over as CEO of STT, Sparkman did not provide many details on the MRAM engine, saying the company is working to patent  the technology before going public with it. But he said he believes the MRAM engine can do for MRAM what SanDisk's invention of All Bit Line (ABL) technology did for NAND flash memory in the early 2000s, providing a mechanism to enhance the performance and reliability of what was an inherently flawed technology.

　　"NAND was a terrible technology," Sparkman said. "But Eli Harari at SanDisk said, 'I know how to take this technology and put some electronics around it to make it work.' "

　　The rest, as Sparkman noted, is history. NAND today is considered a key technology in mobile phones and beyond, with a market that is set to be worth more than $50 billion in 2017.

　　The idea for the MRAM engine grew from technology that STT has been playing with for years as a way to correct for the inherent flaws in MRAM technology — the most widely known being that MRAM is a probabilistic technology as opposed to deterministic, meaning that writing to an MRAM cell will work nearly all the time, but occasionally fail. A big part of the challenge of MRAM development has been trying to make the write error rate as low as possible while compensating for the errors that do occur.

　　STT's engineers "have become experts of correcting for all the flaws in the MTJ," Sparkman said. He added that the engine must be embedded directly into the MRAM array because it's not "a fix after the fact," an approach that STT does not believe will result in MRAM achieving its potential.

　　In addition to pushing what is essentially a new strategy for the company arrived at within the past few months, Sparkman is also far more bullish on the prospects for MRAM to replace DRAM and NAND — both of which are bumping up against fundamental scaling limits — sooner than his predecessor, Barry Hoberman. Many industry insiders, including Hoberman, believe that MRAM will have more luck as an embedded memory technology and replacement for SRAM long before it will make a dent in the massive markets for stand alone DRAM and NAND.

　　"That's not to say that there won't be early adopters," Sparkamn said. "People with the biggest pain points are going to be the first to adopt," he added, citing as an example the military/aerospace market.

　　But Sparkman believes that adoption for MRAM will be far faster than widely believed. "I actually personally believe that this adoption is going to be very fast," he said.

　　With some companies, including Samsung, saying they expect to have MRAM in production next year, "we need to be strapping on our boots and saying 'Where do we play? Where's our piece?' " Sparkman said.

　　MRAM has long been seen as a potential replacement for SRAM, DRAM and flash, but development, which began in earnest in the 1990s, has been slow. To date, only one company, Everspin Technologies, has shipped working MRAM products. Everspin has been shipping MRAM since back in 2006 when it was still part of Freescale Semiconductor. Last August, Everspin became the first vendor to announce it was sampling MRAM with pMTJs,  considered by all vendors developing MRAM to offer the best scalability, shape dependence and magnetic scalability.

　　Today, a host of companies — old and new alike — are scrambling to bring products to market, including the likes of IBM, Intel, Samsung, Fujitsu, Hynix, Qualcomm, Renesas and Toshiba, as well as Avalanche Technology, a startup that like STT is also headquartered in Fremont. Major foundries including TSMC, Globalfoundries and Samsung have all announced plans to offer embedded MRAM technology in the next year or two.

　　The potential size and growth rate of the MRAM market is still largely a matter of debate. Everspin, in documents filed for its IPO last year, estimated that the MRAM market would be worth $1.8 billion this year. An April report by Grand View Research, a San Francisco-based market research and consulting company, estimated that the MRAM market would be worth $4.8 billion by 2025.

　　Sparkman was appointed STT CEO on July 11 by Allied Minds, an IP commercialization firm which has incubated STT since prior to its founding in 2007. Sparkman brings to the job more than 35 years of experience in the semiconductor and wireless industries, including stints at Motorola, Maxim, Samplify Systems, IDT and Spansion.