3D NAND has been in the memory headlines a lot this year. Samsung took the reins last August with their 24-layer
128Gb flash. This past May, they announced a 32-layer chip used in their high-end solid state drives
(SSDs) targeted towards data centers and high-end computers. With their quick advancements in this arena, Samsung seems very confident about the future of 3D NAND. By 2015, they are predicting up to 20% growth
in this segment. When compared to the production timetables available from Toshiba/Sandisk (2015) and Hynix (2016), Samsung has the clear edge in this market.
To continue positioning themselves as the market leader, Samsung announced earlier this month
that they have started mass production of the industry’s first 3-bit, multi-level-cell (MLC) 3D NAND chips. By increasing the number of bits per cell, this new chip reduces the error rate while maintaining a longer lifecycle when compared to triple-level-cell (TLC), which also utilizes 3-bit technology. The 32-layer chips have also doubled Samsung’s wafer productivity over their comparable planar NAND. Samsung has even put together a proprietary etching technology that connects the layers by shooting holes from the bottom up. One of the main applications for Samsung’s newest chip is SSDs
We have also heard about magnetoresistive random access memory
(MRAM) fairly often when it comes to advancements in NAND technology. MRAM has the cache capability of DRAM but designed to prevent data and session loss when the machine is powered on. At the Ceatec expo near Tokyo, TDK demonstrated
a prototype of their MRAM chips. TDK designed their chips with a spin-transfer torque process (STT) which uses the electrons’ angular momentum to create magnetic field changes as it writes data. During the demonstration, TDK’s STT-MRAM chip was tested side-by-side with a NOR flash chip. When completing the same task, the STT-MRAM had a read and write speed that was seven times faster than the NOR. Even though MRAM is still many years from mass production, the demonstration at Ceatec is a big step forward. Plus, TDK’s biggest competitor, Everspin Technologies, has already shipped small quantities of their STT-MRAM products which are being used as cache in SSDs like those from Buffalo Memory.