Comparison of intrinsic gettering and epitaxial wafers in terms of soft error endurance and other characteristics of 64k bit dynamic RAM

Intrinsic gettering (IG) and P/P
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epitaxial wafers are compared in terms of soft error endurance and other characteristics of a 64k bit dynamic RAM. It was confirmed that soft error rate is improved in IG wafers, while it is deteriorated in P/P
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epitaxial wafers. However, when epitaxial layer thickness is reduced to a certain value, the soft error rate tends to be improved. Several other characteristics of 64k bit DRAM's were also evaluated for devices made on IG and epitaxial wafers with various denuded zone (DZ) widths and epitaxial layer thicknesses, respectively.