IBM attracts Crocus to magnetic RAM biz

Big Blue wants stiffer poles

IBM has drafted in Crocus Technology in hope of blossoming its long-running MRAM flash follow-on technology effort. Where this leaves Big Blue's racetrack memory effort is unclear.

Crocus Technology is a developer of magnetoresistive memory and has devised a thermally-assisted Magnetic Logic Unit (MLU), which caught IBM's eye. The two have signed an agreement to jointly develop semiconductor technology combining MLUs with IBM's MRAM (magnetoresistive random access memory).

The agreement includes patent licensing: IBM and Crocus will have mutual access to patents so they can collaborate and integrate magnetic memory technology into chips.

IBM's William Gallagher, a senior manager in the Quantum Computing and Exploratory Magnetic Memories unit, went all misty eyed, saying: "This joint development and patent license agreement with Crocus furthers IBM's longstanding commitment to enabling innovation through cooperation." Translation: we can't do it alone.

The MLU technology should improve IBM's MRAM effort; that's the plan anyway. An MRAM cell is a Magnetic Tunnel Junction (MTJ) - two magnetic layers either side of an insulating layer. The magnetic field direction of the first layer is kept constant, while the field of the second layer can either be aligned to that of the first or it can run in the opposite direction to the first layer.

The direction of magnetism in the variable layer causes a variation in the cell's resistance and, hey presto, we have binary one and zero logic signals defined by high or low resistance levels.

Crocus MRAM: stored data follows the magnetisation direction of the magnetic tunnelling junction.

The MLU technology should help IBM and Crocus to build smaller MRAM cells, down to 90nm and beyond, increasing storage density. It provides more stability to the stored data, meaning the applied magnetisation. Crocus states that its MLU "opens the way to implementation of NAND configurations in magnetic memory, which was previously possible only in flash memory technology. MLU NAND memory can be two to four times denser than conventional magnetic memory with the added benefit of full random access."

Crocus Technology's exec chairman, Bertrand Cambou, said: "MLU has the potential to replace SRAM, DRAM, NAND, NOR and OTP in many stand-alone and embedded memory products. Because MLU's NOR, NAND and XOR capabilities are built on a single wafer manufacturing process with different design architectures, they can be easily integrated into system-on-chip."

Crocus has previously said it will establish volume production of MLU-based products in 130nm at its foundry partner TowerJazz Semiconductor, as well as at its new Russian subsidiary Crocus Nano Electronics (CNE) for 90nm, 65nm, 45nm and smaller lithography. Crocus said it plans to deploy the process technology resulting from the joint development with IBM at the CNE manufacturing venture.

IBM said that its "MRAM technology promises significant advantages over competing memory technologies including low power usage, high speed, unlimited endurance (read and write cycles), and inherent non-volatility meaning data can be retained even if power is discontinued. MRAM has the potential to enable 'instant-on' computers and longer battery life for mobile computing devices".

Sounds a bit like racetrack memory to me. So IBM obviously has its glam Almaden Research Centre's racetrack memory effort ongoing alongside this separate MRAM deal with Crocus. There are no sure bets in the post-NAND memory race and Big Blue knows it. ®