Improve signal integrity performance by using hybrid PCB stackup

FR4 is a commonly used material in industry to build printed circuit boards. However signals propagating in this media have significant attenuation when date rate gets higher and higher, gating the solution space. Low loss materials can be considered to enable longer board routing but they are very costly for most of commercial platforms. In this paper, hybrid PCB stackup is investigated. The investigation focuses on full channel signal integrity analysis. Simulations for SATA3 and PCIE3 show noticeable improvement of using this hybrid stackup. Such a hybrid is normally less costly than all low loss PCB stackup, thus achieving a good compromising between cost and performance for PCB design and manufacturing.