A Novel Manufacturing Approach of Phase-change Heat Sink for High-power LED
Abstract Heat removal in packaged high-power light-emitting diode (LED) chips is critical to device performance and reliability. Thermal performance of LEDs is important in that lowered junction temperatures extend the LED's lifetime at a given photometric flux. Optionally, lower thermal resistance can enable increased brightness operation without exceeding the maximum allowable junction temperature for a given lifetime. The goal of this study is to improve the thermal characteristics of high-power LED package by using phase change heat sink. The heat-release characteristics of high-power LED package are analyzed and a novel phase change heat sink with 3D integral-fin boiling structures for high-power LED is developed. Two different fin structures were obtained in grooves formed with chopping-ploughing-extrusion compound forming technology and observed by scanning electron microscope (SEM).
The computer controlled Laserthermia system by the method of using double ::: channel endoscope with the contact frosted probe and a thermocouple was reported ::: previously.25 In this paper, the single channel method with the new single ::: laser delivery system was studied experimentally. Especially hyperthermal effect ::: by the newly developed Hybrid Laserthermia feedback probe(Hybrid probe) was discussed ::: comparatively with the effects by the interstitial contact probe. The Hybrid ::: probe could be possible to treat clinically more accurate Laserthermia in ::: the near future.