From: Kelly Kovalovsky, Raw Card Quality Engineering Phone:704-595-7336 Tie Line:795-7336 FAX Ext. 4727 Subject: 0.020" pitch SMT pad widths We design our 0.020" pitch SMT pads at an 0.011" pad width. Our specification calls for these pads to finish at 0.011" +/- 0.002" as measured at the laminate. The problem is that the pads tend to come in at 0.0085" to 0.0095" at the top of the pad due to etch factor. Our SMT paste screens are manufactured at 0.011" nominal. It is the dimension at the top of the pad that is important to the card assembler. We have requested that the raw boards be built to meet 0.011" +/- 0.002" as measured at the top of the pad. This involves compensating the artwork to meet our requirement. My questions to the raw board manufacturers are: 1) Is 0.011" +/- 0.002" as measured at the top of a 0.020" pitch pad a manufacturable feature at an acceptable yield? 2) If so, what comp factor would you use to achieve this finished dimension? 3) Does board finish (HASL, entek, etc.) put any limitations on your ability to manufacture this? IBM Microelectronics Division 6800 IBM Drive MG12/251 Charlotte, NC 28262-8563