TechNetters, OK after speaking to a couple of industry friends, this is what we have come up with. I will leave it to them to speak up and identify themselves, if they wish. I have written this up in IPC-A-610 format and have tried to cover all situations for Class 2 and 3 products in particular. If we can nail this, I would like to present this to the IPC as the first IPC draft doc essentially hammered out by out TechNet community. Comments readily accepted! Bev RIM Workmanship Standards for BGA and CSP Underfills Target - Class 1,2,3 * Component requiring underfill completely underfilled with a good fillet all the way around, the fillet just approaching the maximum component body height, completely cured, no encroachment onto other components and no voiding whatsoever Acceptable - Class 3 * At least 50% fillet height up the side of the component body * Small pin holes and voids are permissible provided they do not exceed 5% of fillet surface area and have a maximum diameter of 0.5 mm (0.020 inches). Acceptable - Class 1,2 * Component requiring underfill underfilled such that all balls are covered, but no evidence of an exterior fillet, no encroachment onto other components and no voiding whatsoever * Component requiring underfill underfilled such that all balls are covered, with or without an exterior fillet, no encroachment onto other components and only small voids, not touching any solder joints * Component requiring underfill underfilled such that all balls are covered, with or without an exterior fillet, no encroachment onto other components and even large voiding, but not touching any solder joints * A void or voids less than or equal to 50% around the perimeter of one or more solder joints Defect - Class 1,2,3 * Underfill completely missing from components where it is required * Underfill not completely covering all the peripheral solder joints * Voiding such that a void traverses the distance between two or more solder joints under the array device requiring underfill * A void or voids more than 50% around the perimeter of one or more solder joints * Material extending on to the top of the BGA or CSP * Uncured material Special Conditions - Class 1,2 * Encroachment onto other components, but meeting all other criteria above for target or acceptable conditions will be dealt with as a pass/fail on a case-by-case basis --------------------------------------------------------------------- This transmission (including any attachments) may contain confidential information, privileged material (including material protected by the solicitor-client or other applicable privileges), or constitute non-public information. Any use of this information by anyone other than the intended recipient is prohibited. If you have received this transmission in error, please immediately reply to the sender and delete this information from your system. Use, dissemination, distribution, or reproduction of this transmission by unintended recipients is not authorized and may be unlawful. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------