Ans (1) lot to lot :不同lot之间的差异性, due to EQ, material, environmental shift(2) within lot waferto wafer:同一个lot中,不同wafer之间的差异性, due to batch run conditional shift. E.g. Lensheating, CVD film thicknes
Ans Vbd: pattern 2000×2000um2, die no=72ea, Vbd>= 8V for oxidethickness 70A, Vbd>=12V for oxide thickness 115A. Vbd>=6.5V, pass orVbd<=2.5V, mode A failure, 2.5V < Vbd< 6.5V, B mo