Benchmark study of metal core thermal laminates

New applications such as the use of High Brightness Light Emitting Diodes (HB-LED´s) for general lighting have brought about significant demand for thin dielectric materials laminated to metal substrates such as aluminum and copper. Conventional FR-4 printed wiring laminates have limited thermal performance due to the poor thermal conductivity. To maximize thermal performance, it is necessary to minimize the thermal resistance of the laminate structure. To accomplish this, the thermal conductivity of the dielectric must be maximized and the dielectric thickness must be minimized. This paper summarizes the results of a benchmark study comparing the thermal performance of DuPont CooLam™ and three competitive structures measuring Junction-to-Case Thermal Resistance (RΘ_jc) and using thermal impedance as a figure of merit for comparing thermal performance of substrates, a primary metric commonly used in the LED packaging industry. To ensure uniform and unbiased results all test samples were fabricated by the same PWB fabricator and the testing was conducted by an independent laboratory.