Raw Material Choices for PCBs

This article provides recommendations for choosing materials to manufacture multilayer PCBs that achieve two critical requirements: limit manufacturing problems (e.g., bowing or twisting, as well as mis-registering; and meeting performance standards. A successful PCB production begins with proper material selection. For a low number of board layers, your PCB manufacturers default materials are usually your best choice as they are reliable and cost effective. However, when designs have special requirements or incorporate a high number of layers, then it is worth a designer’s effort to become more familiar with the available material options, in order to make the best decisions for their product. To get more news about Isola 370HR PCB, you can visit pcbmake official website.

The most important material for PCB manufacturing is raw laminate. It also represents the largest cost of all other materials needed to produce a multilayer PCB. Raw laminate has a critical impact for the prices and the delivery time of PCBs. Due to the amount of material needed for PCB fabrication, it is essential to optimize the size of your designs; even a small difference in size can result in a significant difference in cost. Different materials incur different costs and possess different characteristics, but higher quality laminates are typically also more expensive. The following are some of the main characteristics to take note of when comparing properties of different laminates:

Tg = Glass Transition Temperature – Temperature at which a critical change of physical properties will occur. In the case of laminates, it transitions from a hard, glassy material into a soft, rubbery material

Td = Decomposition Temperature - Temperature at which the laminate chemically decomposes

Dk = Dielectric Constant (also referred to as εr in electromagnetics) – Indicates the relative permittivity of an insulator material, which refers to its ability to store electrical energy in an electric field. For insulating purposes, a material with lower dielectric constant is better and in RF applications a higher dielectric constant may be desirable

Df = Dissipation Factor – Indicates the efficiency of an insulating material by showing the rate of energy loss for a certain mode of oscillation, such as mechanical, electrical, or electromechanical oscillation

Our fabrication facilities are located in China, so it is advisable to choose high-quality local laminates in order to minimize shipping cost and lead time. The Shengyi S1000-H (Tg 150) laminate is generally our default choice for a high-performance, mid-Tg laminate. Shengyi S1000-H is comparable to Isola FR406 (Tg 150), a standard North American laminate option. As outlined in Table 2 below, FR406 does slightly outmatch Shengyi S1000H in terms of Dielectric Constant and Dissipation Factor, but some clients may be willing to compromise on these factors for a lower cost and/or a faster lead time.