Low profile inductor with lateral flux for 3D integrated POL (2007)
With the increased popularity of portable electronics, improved integrated solutions are desired to improve the low power DC/DC converter technology. With the state of the art designs, the bulky magnetic components are a major barrier for integrating a DC/DC converter into a single chip. The 3D integrated solution that uses a low profile inductor as the substrate is one possible method to integrate the magnetic component with the active component. Previously, the embedded winding with vertical flux is the conventional way to make low profile inductor. With this vertical flux structure, the inductance density will be suffered when the core thickness is very thin. In order to solve this problem, CPES proposed low profile inductor structure with lateral flux pattern, which can have large inductance density even with very thin core thickness. A high low profile inductor with coupled lateral flux was fabricated by using LTCC material.