Life-Cycle Assessment of Flash Memory
Solid state drives (SSD) show the potential for environmental benefits over magnetic data storage due to their lower power consumption. In this study, a complete life-cycle assessment (LCA) of flash memory over five technology generations (150 nm, 120 nm, 90 nm, 65 nm, and 45 nm) is presented to investigate this idea. The inventory of materials and energy used in NAND flash manufacturing is based on process data, while the impacts associated with chemicals, equipment, fab construction, electricity, and water are determined using economic input-output life-cycle analysis (EIO-LCA) and hybrid LCA. Sensitivity analysis shows that the most influential factors which can reduce the environmental impact of flash memory are perfluorinated compound (PFC) abatement in wafer fabrication and electricity use in manufacturing. A comparison between the complete life-cycle of 96 GB of flash memory and the use and transportation stages of a 2.5” hard disk drive (HDD) shows that the flash memory consumes less primary energy and water and results in lower global warming potential (GWP), ecotoxicity and smog formation than the magnetic HDD, though the relative benefit of flash-based SSD in other impact areas cannot be determined without a complete LCA of HDD.
KeywordsImpact Category Global Warming Potential Hard Disk Drive Flash Memory Wafer Fabrication
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