After attending Curtis Zwenger’s presentation introducing Amkor’s latest contribution to the package-on-package (PoP) family based on the company’s proprietary through mold via (TMV) technology, I feel compelled to correct some misinformation I read last week on a colleague’s blog.
Although TMV appears to borrow conceptually from TSV technology, it is by no means meant to be an alternative technology to TSV. In fact, the two technologies address 3D stacking at different levels, and were developed to address different issues. TMVPoP is a 3D package configuration, and the technology was developed to address PoP warpage issues, overall package size, improve fine-pitch stacking and improved density and signal integrity at the package level. On the other hand, TSV is a 3D IC integration building block for stacking the chips themselves to improve performance, form factor, and signal process packing density. And according to Eric Beyne of IMEC, high density TSV solutions will ultimately be required to optimize system partitioning.
In actuality, according to Lee Smith of Amkor, not only is TMV NOT an alternative to TSV, it was designed to support TSV stacked chips in its bottom package, in addition to flip chip and wire bond designs. I hope this helps clear up any confusion.
Zwenger’s presentation shared data proving TMV’s PoP benefits such as demonstrating the smallest warpage at 25 and 260°. TMV flattens out the package at the corners and improves fine pitch stacking. As a result, when compared to bare die flip chip POP, lower warpage with TMV enables substrate thickness and PoP stack up reductions. Additionally, improved design rules allow for increased die size by 30%. Zwenger also said TMVPOP meets package requirements for high density and signal integrity.
The Device Packaging Symposium has just concluded for the year, but as I suspected it supplied me with enough material to write about for days. So there’s more to come. – F.v.T.
