Functional embedded RF circuits on multi-layer printed wiring board (PWB) process

For getting more economy and smaller electronic products, technology of system in package (SiP) could complement the technology of system on a chip (SoC) perfectly. About SiP technology, we chose integral substrate technology to realize embedded passives, and used fine process such as high density interconnection (HDI) technology with a special dielectric material to achieve specific circuit functions. The special material is a high dielectric constant (Hi-DK; DK>40 @ 1GHz) material, which is suitable for Multi-Layer Printed Wiring Board (PWB) lamination process, and it was used to fulfill embedded capacitors. In the past years, we had utilized the technology to design Bluetooth/sup TM/ module, or other RF circuits. Furthermore, this technology is more economy than any other SiP processes, like Low Temperature Co-fired Ceramic (LTCC) substrate or silicon substrate, because it bases on the conventional PCB process. In this paper, we introduce not only the embedded capacitors but also some functional embedded passives in RF front-end circuits design on the Hi-DK organic substrate. Moreover, the RF front-end circuits include some functional passive elements: band pass filter, balun, and antenna, etc. Thus, in high frequency circuits, this kind organic substrate can reduce the module size, and in high-speed digital circuits, it also provides inexpensive decoupling capacitors. In the future, we will use this cost-effective technology to design analog and digital circuits on the same board, and the technology of SiP and SoC can be co-designed.