Stacking singulated dies is an efficient way to create die stacks; IMEC uses this so-called die-to-die (D2D) stacking approach often to manufacture small to medium volumes of test chips. There is a need to perform a post-bond test on still-unpackaged (???bare???) D2D stacks, if only to avoid unnecessary packaging costs. This paper presents an approach to perform automatic stepping and probing on arrays of D2D stacks pick-n-placed (PnP'd) on a carrier substrate. We describe an algorithm for Cascade Microtech's CM300 probe station to automatically correct small PnP misalignments. Subsequently we present experimental results for PnP'd D2D stacks on three types of carriers: (1) dicing tape on tape frames for ??100mm wafers, (2) sheets of single-sided thermal-release tape, and (3), ?? 300mm carrier wafers with double-sided thermal-release tape. Finally, we describe adaptations to the CM300 probe station to be able to handle 400mm-wide tape frames for, ?? 300mm wafers.
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