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⁺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⁺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.