Title :
A statistical study of defect maps of large area VLSI IC´s
Author :
Koren, Israel ; Koren, Zahava ; Stapper, Charles H.
Author_Institution :
Dept. of Electr. & Comput. Eng., Massachusetts Univ., Amherst, MA, USA
fDate :
6/1/1994 12:00:00 AM
Abstract :
Defect maps of 57 wafers containing large area VLSI IC\´s were analyzed in order to find a good match between the empirical distribution of defects and a theoretical model. Our main result is that the commonly employed models, most notably, the large area clustering negative binomial distribution, do not provide a sufficiently good match for these large area IC\´s. Only the recently proposed medium size clustering model is close enough to the empirical distribution. An even better match can be obtained either by combining two theoretical distributions or by a "censoring" procedure in which the worst chips are ignored. Another goal of the study was to find out whether certain portions of either the chip or the wafer had more defects than the others.<>
Keywords :
VLSI; monolithic integrated circuits; probability; statistical analysis; censoring procedure; defect maps; empirical distribution; large area VLSI IC; medium size clustering model; negative binomial distribution; statistical study; theoretical model; Conferences; Fault tolerant systems; Integrated circuit modeling; Performance analysis; Random variables; Semiconductor device measurement; Semiconductor device modeling; Testing; Time measurement; Very large scale integration;
Journal_Title :
Very Large Scale Integration (VLSI) Systems, IEEE Transactions on