Issue link: https://iconnect007.uberflip.com/i/978458
MAY 2018 I PCB007 MAGAZINE 35 This time-consuming process needs to be sped up by interacting during the alpha and beta stages of the material testing so necessary modifications are done before launching it to market. Here again, the standardization of the building blocks comes in handy for the reus- ability of simulation data. Both electrical and mechanical properties need to be considered. Another consideration is the supply chain for the material, so it can be produced as locally Material Group Dk Df Frequency [GHz] Main Thickness [mm] Thermal Conductivity [W/m/K] CTE X and Y FR-4.1* FR-4.1 high Tg 4.3 +/- 0.2 < 0.015 < 5 0.150 (6 mil) 0.114 (4.5 mil) FR-4.1 low CTE 4.3 +/- 0.2 < 0.015 < 5 10 ppm FR-4.1 low Dk 3.9 +/- 0.1 < 0.015 < 5 0.114 (4.5 mil) Low Df, Dk and CTE 3.6 < 0.003 < 5 0.150 (6 mil) 10 ppm Low Df and low Dk 3.6 +/- 0.1 < 0.003 < 5 0.508 (20 mil) > 0.6 Low Df and high Dk > 6 < 0.003 < 5 0.508 (20 mil) > 0.6 Microwave 3.6 +/- 0.1 < 0.004 50 0.254 (10 mil) 0.127 (5 mil) *FR-4.1 = HFFR4 (halogen-free) Material Group Dk Df Frequency [GHz] Main Thickness [mm] Thermal Conductivity [W/m/K] CTE X and Y FR-4.1 high Tg 4.3 +/- 0.2 < 0.015* < 15 0.150 (6 mil) 0.114 (4.5 mil) HDI PCB < 3.6 < 0.005 < 40 Prepreg system < 10 ppm Antenna ~ 1 < 100 0.5 –1.0 Microwave ~ 3 < 0.002 < 100 Prepreg system * Low variation on Df over temperature Table 3: Current halogen-free PCB material needs. *FR-4.1 = HFFR4 (halogen-free). Table 4: Future halogen-free PCB material needs. *Low variation on Df over temperature.