There has been much industry activity lately on this topic. Basically, in 1986 Ray Prasad and others from Intel presented data showing that plastic ICs undergoing surface mount soldering were delaminating or cracking and causing field failures. The Surface Mount Council commissioned a white paper, which was finished in 1988. A special IPC task group, chaired by Prasad, then developed a specification--IPC-SM-786-- which defined levels (for classifying the susceptibility of certain types of components to delamination) and gave preconditioning and handling guidelines, including drypacks and nitrogen storage. In 1995, IPC released the "A" revision of IPC-SM-786. This industry standard is used by many manufacturers and suppliers. Other standards also available are JESD A112/A113 from JEDEC and EIA 4071A and ED407 from Electronics Industry Association Japan. The JEDEC and IPC standards are fairly similiar with regard to the specific requirements, although the IPC standard offers much more baackground information and tutorial. Six levels of classification are designated in the standard. We have found the industry really only uses three or four of these, although a new level probably needs to be developed between the current levels 2 (1 year out of bag at less than 30C/60%RH) and 3 (1 week at 30C/60%RH). For a full description of the baking parameters and handling, see the standard. In March 1996, 30-odd industry participants (including John Tsutsui of Rockwell) attended an ITRI-SEMATECH sponsored workshop in Dallas at which we developed a number of industry needs. One of these is a single specification for classification and handling of moisture sensitive ICs. With that mandate, IPC and JEDEC formed a joint task group to carry out this goal. The first meeting of this task group is next week at the IPC office in Northbrook, IL. ANSI has designated J-STD-020 as the number for this future standard. It is important to note that Amkor and other component suppliers have shown that although delamination is a red flag, there is no one-to-one correlation between delam and failure. IPC-SM-786A is available from IPC's order department: email [log in to unmask], or call 847-509-9700, ext. 348. Price is $15 for IPC members/30 for nonmembers. Mike Buetow IPC Technical Staff 2215 Sanders Road Northbrook, IL 60062 P: 847-509-9700, ext. 335 F: 847-509-9798 [log in to unmask] On Wed, 5 Jun 1996, David T. Novick wrote: > On 5 June 1996 a request from manufacturing engineering was placed for > forwarding to TechNet. This request is as follows: > > Several programs going into production will be using plastic parts. > There parts tend to absorb moisture and will crack during the reflow > process. Since our entire experience has been with military > packaging, we are not certain what to expect from plastic components. > We are requesting information on the packaging and storage of these > parts. We also would like to know the baking parameters typically > required to mitigate any risk during the soldering processes utilized > throughout industry. It is our understanding that if these parts are > exposed to humidity for a period of time we need to vacuum bake them. > However we do not know for what period of time and at what > temperatures. Since this is an area which is fairly new to us, we > need all the feedback we can get. > > Thanks for your help. > > Rosaura Corral-Perez > >