设计并制备了51 V高压LED。对器件进行了大电流冲击试验并对器件的损毁原因进行了分析。运用有限元分析软件ANSYS对LED关键结构部位进行参数化建模及热分布模拟，得到其稳态的温度场分布；然后经过与红外热像仪成像图对比，得出电极烧毁的原因在于芯粒连接处的电极过薄过窄而导致的电阻过大，为后续设计更可靠的高压LED提供了参考。对芯片分别进行蓝光及色温5 000 K的白光封装，并分别测量了热阻，涂覆荧光粉的白光灯珠的热阻要比没有涂覆荧光粉的蓝光灯珠高约4 ℃/W。同时，51 V高压LED的热阻比1 W大功率LED要高，说明高压LED的散热性能比常规LED要差，这可能与高压LED具有深沟槽及众多的互联电极结构有关。

51 V high voltage LED (HV LED) was designed and fabricated. Firstly, the HV LED was tested by large current attack, then the damage reason was analyzed. The key parts thermal parameters distribution model of HV LED was simulated by using finite element analysis software ANSYS, and the steady distribution of temperature was achieved. By analyzing the infrared thermal image, the reason of HV LED failure after large current attack was gotten. The core particle electrode burned at the connection part which was thin and narrow, so the resistance was large. It provided a good reference for the sequence design of more reliable HV LED. Meanwhile, the chips were packaged into white lamp with color temperature of 5 000 K and blue lamp, respectively. The thermal resistance of the white lamp was about 4 ℃/W higher than the blue lamp without phosphor coating, and it was also higher than the conventional 1 W LED. The deep groove structure and numerous interconnected electrode structure of HV LED may be the reason of the thermal performance of high voltage LED worse than the conventional 1 W LED.