Known Good Die (KGD)

A Known Good Die (KGD) is defined as “a package type fully supported by suppliers to meet or exceed quality, reliability, and functional data sheet specifications, with non-standardized (die specific) but completely and electronically transferable mechanical specifications”. In other words, the category of challenges associated with KGD are no different than those faced by any customer using a new or different package type. Electrical performance and power dissipation values and variations, mechanical specifications, handling issues, cooling, attachment to the next level of assembly, etc., all must be reevaluated and solutions found whenever the package changes, even though the die remains identical. Hence, KGD is no more than a different package type for a known die that incorporates mechanical specifications that cannot be standardized (unless or until die designers agree on standard die sizes and pad layouts, etc.). The challenges associated with KGD usage may be greater than with standardized packaged dice because of less standardization of mechanical specifications, handling of bare dice, etc. The ben-efits, challenges, and approaches to KGD usage are discussed in this chapter.