The thermal conductivity of LED under the influence of vacuumsputtering films

摘要

The thermal conductivity has the important influence in quantum effect of light emitting diodes (LED) especially in high brightness light emitting diodes (HB LED). One of the biggest challenges is efficient heat transfer from PCB to aluminum plate when it base on printed circuit board (PCB). Because it enables transfer the heat from electric device to the aluminum plate, which completely removes the heat. In this study, alumina (Al203), alumina nitride (A1N) and zinc sulfide (ZnS) films soldered the HB LED lamps to enhance the heat transfer. All of the films were fabricated onto 1070 aluminum substrate by vacuum sputtering technology. The dielectric coatings were characterized by several subsequent analyses, especially the measurement of thermal resistance. The X-Ray diffraction (XRD) diagram analysis reveals three kinds of ceramic thin films were successfully grown on the individual substrate. Moreover, the alumina nitride coating has low sheet resistivity, high hardness, high critical load, and good thermal conduction, 200 W/m-K, as compared to those of Al203 and ZnS films.