Improved Structure for Package Substrates with Embedded Thin-Film Capacitor

Embedding thin-film capacitors (TFC) in a package substrate is a technology aimed at improving the performance of power supply. The package substrate that we have developed and produced embeds TFCs into the core layer of a built-up substrate. Using this substrate promises to dramatically reduce the impedance on power supply lines and provide a stable power supply to the integrated circuit (IC) chip, resulting in improved performance of electronic devices. In this paper, we propose three improved structures for package substrates with embedded TFCs: the first is an asymmetric single-sided embedded TFC structure that uses the warpage-control layer; the second is a standalone embedded TFC structure that places solitary TFCs directly under the IC chip only; the third is a coreless embedded TFC structure that embeds TFCs in a coreless substrate. These technologies promise to help lower the cost of package substrates, increase their efficiency, and reduce their thickness.