The impact of areal density and millions of square inches (MSI) of produced memory on petabyte shipments of TAPE, NAND flash, and HDD storage class memories

Increases in annual petabyte (PB) shipments for storage class memories (SCM) are driven by both increases in areal density and increases in manufacturing capacity. Increases in areal density tend to reduce cost per bit while increases in manufacturing capacity are cost neutral or slightly increase cost per bit. This paper surveys the last five years of PB shipments, areal density, revenue, and cost per bit for magnetic tape (TAPE), hard disk drives (HDD), and NAND flash to study manufacturing and cost trends for storage class memories. First, using the five year data for PB shipments and areal density values for TAPE, HDD and NAND flash, this paper applies a manufacturing measure used by semiconductors, millions of square inches or MSI of produced memory, to TAPE, HDD, and NAND flash in order to compare manufacturing requirements for these three SCM technologies. The MSI calculations shows for HDD and NAND, with slowing areal density increases, that manufacturing investments will be required for sustaining PB shipment growth while for TAPE modest investment in manufacturing capacity is required. The MSI calculations also show that the cost of NAND replacing HDD is prohibitive based simply on present day manufacturing capacity and show that for HDD to adopt processing requirements for patterned media, the next proposed areal density improvement for HDD, would require significant manufacturing investments. Second, using the five year data for PB shipments and revenue for TAPE, HDD, and NAND flash, trends in cost per bit for the SCM technologies can be determined and related to both technology innovations, i.e. lithography for NAND flash and predictable areal density increases for TAPE, and to external market factors, i.e. industry consolidation for HDD and mobile computing for NAND flash. Lastly, while 2012 PB shipments for TAPE, HDD, and NAND flash totaled 430,000 PB, dominated by HDD with 380,000 PB, perceived information creation in 2012 was over 1,300,000 PB, posing the question to SCM manufacturers as to how information is stored in today's environment.