NAND scaling has already extended further than expected, but the search for alternative non-volatile memories continues apace. At ISSCC 2010 in San Francisco next month, progress in a number of alternatives will be presented:
A 64Mb STT (Spin Transfer Torque)-MRAM which is the highest density yet achieved. The cell size is 0.358μm2 in 65nm CMOS, and it has a 30ns access time.
A 64Mb CMOx memory, the technology being pioneered by Unity Semiconductor, which is the highest density yet achieved for CMOx. It is made in 0.13μm CMOS in a four-layer 0.17μm2 cross-point-cell array. Using the multi-layer capability, this memory is scalable to 64Gb capacity.
The fastest 12ns 4Mb embedded PCM (Phase-Change Memory) in 90nm CMOS ever reported. The fast read is achieved by using low-voltage MOS in the hierarchical column decoder
A 1Gb PCM, the highest density PCM ever achieved, made in 45nm CMOS with 1.8V operation. It has features the fastest-ever read/write performance with 266MB/s and 9MB/s read/write throughputs respectively.
Another way of getting to higher memory density will very likely be 3D stacking and, at ISSCC2010, the first prototype of a commercially-viable cost-effective 3D-stacked IC will be demonstrated by IMEC. It is based on a new analysis of methodologies for the use of Through-Silicon Vias (TSVs).
TOMORROW MORNING: Ten Black Swans For 2010