Die Products Standards: Development
Standards Contents
Die Products Standards - The Critical Link
Certain trends in the die products industry support the notion of an expanding market and indicate that the timing is critical for a die products standard, and both suppliers and customers are taking a hard look at any remaining barriers to adoption. Several formal standardization efforts for die products are underway now. See a list of existing standards.
The Die Products Consortium is taking a leading role in developing standards that address provisions for quality and reliability metrics crucial for die assembly and a performance based approach that differentiates it from past standardization efforts.
DPC Standards activities
In 1993, the Defense Advanced Projects Agency (DARPA) funded two Austin, Texas based consortia to develop a standard for Known Good Die (KGD). The two consortia represented the die supplier community (Sematech) and the die user community (Microelectronics and Computer Technology Corporation - MCC). A joint task group of members of the two consortia developed the base document for KGD, termed the Procurement Standard for Known Good Die, as well as addenda for TAB and flip chip devices. The base document, along with the addenda, was forwarded to JC-13, the JEDEC Government Liaison subcommittee, which adopted an edited version of the documents as JESD 49 in February, 1996.
JESD 49 Procurement Standard for Known Good Die (KGD)
This standard was created to facilitate the procurement and use of high reliability semiconductor
microcircuits or discrete devices provided in bare die form. It provides requirements and guidance
to bare die suppliers for as-delivered performance, quality and long term reliability expected of
this product type. It also reflects the special needs of KGD product customers in terms of design
and application data. It stresses that cooperation between suppliers and users is essential.
This standard is seen in the industry as primarily a guideline that gives users a checklist of issues to be addressed in the transaction. The DPC recently initiated an upgrade cycle by JEDEC's JC-13 and JC-14 taskgroups, which are currently underway.
IEC 62258: Semiconductor die products - Minimum requirements
for procurement and use
A project team of TC47, the semiconductor devices technical committee, has been developing
IEC62258 under the direction of Jim Wolbert of Chip Supply. The DPC submitted a new item work
proposal in 2001 in response to the European standards body, CENELEC, adopting a die products
standard that was deemed to be excessively complex and restrictive for die suppliers. Part 1 of
the standard contains the minimum requirements for die products information exchange, and will,
in all likelihood, be adopted in 2004.
IEC 62258, part 1 provide definitions, requirements for handling, shipping and storage requirements and requires disclosure of quality and reliability metrics for bare semiconductor die, with or without connection structures, and minimally packaged semiconductor die (now termed wafer level CSPs in the industry). The standard focuses on the unique information that must be available for successful application of die products in electronic assembly.
Issues
An essential function of standardization is to facilitate communication between producer and customer by specifying what is available and giving confidence that the ordered goods will comply with the requirements as stated . Definitions of terms, a description of procedures, and statements of required results provide the context of any standard, and aspects of each of these are still being debated among the standardization teams.
A quantitative definition of Known Good Die has proved elusive.
In standards work generally, when product characteristics are specified, the standard test methods must be designated. The DPC Fault Modeling and Test Coverage Description project is a step in this direction, but much work remains to be done. Each market segment has differing requirements for quality and reliability of the individual die products, and each has a different cost target. Getting agreement on one definition for all markets is not possible, and making different definitions based on markets is impossibly complex.
The DPC is making an effort to change the focus for die products from prescriptive to performance based.
Rather than specifying the tests and screens that should be used to qualify die to a certain level, it is more effective to specify the quality and reliability levels needed, putting the burden on the supplier to provide evidence of compliance. This requirement means that the supplier will have to have an incentive for providing the evidence.
Next Steps
The JC-13 committee has agreed to broaden the scope of JESD49 to include die products (it originally focused exclusively on KGD), and will add a section detailing the specific requirements for KGD, or other special die requirements that supercede the base document. The DPC standards project participants would like your input - please take a moment to complete our standards survey.