设计并制备了110V Ga N基交流高压LED芯片,阐述了其制作的关键工艺,并通过I-U-L曲线,近场光型等手段进行表征,该芯片具有良好的光电性能,通过两并两串方式封装在陶瓷支架并匹配相应的限流电阻组装成灯具,对比测试了灯具初态和稳态下的...设计并制备了110V Ga N基交流高压LED芯片,阐述了其制作的关键工艺,并通过I-U-L曲线,近场光型等手段进行表征,该芯片具有良好的光电性能,通过两并两串方式封装在陶瓷支架并匹配相应的限流电阻组装成灯具,对比测试了灯具初态和稳态下的光电参数。展开更多
High-power and high-reliability GaN/InGaN flip-chip light-emitting diodes （FCLEDs） have been demonstrated by employing a flip-chip design, and its fabrication process is developed. FCLED is composed of a LED die and...High-power and high-reliability GaN/InGaN flip-chip light-emitting diodes （FCLEDs） have been demonstrated by employing a flip-chip design, and its fabrication process is developed. FCLED is composed of a LED die and a submount which is integrated with circuits to protect the LED from electrostatic discharge （ESD） damage. The LED die is flip-chip soldered to the submount, and light is extracted through the transparent sapphire substrate instead of an absorbing Ni/Au contact layer as in conventional GaN/InGaN LED epitaxial designs. The optical and electrical characteristics of the FCLED are presented. According to ESD IEC61000-4-2 standard （human body model）, the FCLEDs tolerated at least 10 kV ESD shock have ten times more capacity than conventional GaN/InGaN LEDs. It is shown that the light output from the FCLEDs at forward current 350mA with a forward voltage of 3.3 V is 144.68 mW, and 236.59 mW at 1.0A of forward current. With employing an optimized contact scheme the FCLEDs can easily operate up to 1.0A without significant power degradation or failure. The li.fe test of FCLEDs is performed at forward current of 200 mA at room temperature. The degradation of the light output power is no more than 9% after 1010.75 h of life test, indicating the excellent reliability. FCLEDs can be used in practice where high power and high reliability are necessary, and allow designs with a reduced number of LEDs.展开更多
The light extraction enhancement of freestanding GaN-based flip-chip light-emitting diodes （FS- FCLEDs） using two-step roughening methods is investigated. The output power of LEDs fabricated by using one-step and tw...The light extraction enhancement of freestanding GaN-based flip-chip light-emitting diodes （FS- FCLEDs） using two-step roughening methods is investigated. The output power of LEDs fabricated by using one-step and two-step roughening methods are compared. The results indicate that two-step roughening meth- ods show more potential for light extraction. Compared with flat FS-FCLEDs, the output power of FS-FCLEDs with a nanotextured hemisphere surface shows an enhancement of 90.7%.展开更多
GaN based MQW epitaxial layers were grown on Si （111） substrate by MOCVD using AIN as the buffer layer. High light extraction LEDs were prepared by substrate transferring technology in combination with thin-film and...GaN based MQW epitaxial layers were grown on Si （111） substrate by MOCVD using AIN as the buffer layer. High light extraction LEDs were prepared by substrate transferring technology in combination with thin-film and flip-chip design. The blue and white 1.1 × 1.1 mm2 LED lamps are measured. The optical powers and external quantum efficiency for silicone encapsulated blue lamp are 546 mW, and 50.3% at forward current of 350 mA, while the photometric light output for a white lamp packaged with standard YAG phosphor is 120.1 lm.展开更多
文摘High-power and high-reliability GaN/InGaN flip-chip light-emitting diodes （FCLEDs） have been demonstrated by employing a flip-chip design, and its fabrication process is developed. FCLED is composed of a LED die and a submount which is integrated with circuits to protect the LED from electrostatic discharge （ESD） damage. The LED die is flip-chip soldered to the submount, and light is extracted through the transparent sapphire substrate instead of an absorbing Ni/Au contact layer as in conventional GaN/InGaN LED epitaxial designs. The optical and electrical characteristics of the FCLED are presented. According to ESD IEC61000-4-2 standard （human body model）, the FCLEDs tolerated at least 10 kV ESD shock have ten times more capacity than conventional GaN/InGaN LEDs. It is shown that the light output from the FCLEDs at forward current 350mA with a forward voltage of 3.3 V is 144.68 mW, and 236.59 mW at 1.0A of forward current. With employing an optimized contact scheme the FCLEDs can easily operate up to 1.0A without significant power degradation or failure. The li.fe test of FCLEDs is performed at forward current of 200 mA at room temperature. The degradation of the light output power is no more than 9% after 1010.75 h of life test, indicating the excellent reliability. FCLEDs can be used in practice where high power and high reliability are necessary, and allow designs with a reduced number of LEDs.
基金supported by the National Natural Science Foundation of China(Nos.61274040,61274008)the National Basic Research Program of China(No.2011CB301902)the National High Technology Program of China(No.2011AA03A103)
文摘The light extraction enhancement of freestanding GaN-based flip-chip light-emitting diodes （FS- FCLEDs） using two-step roughening methods is investigated. The output power of LEDs fabricated by using one-step and two-step roughening methods are compared. The results indicate that two-step roughening meth- ods show more potential for light extraction. Compared with flat FS-FCLEDs, the output power of FS-FCLEDs with a nanotextured hemisphere surface shows an enhancement of 90.7%.
文摘GaN based MQW epitaxial layers were grown on Si （111） substrate by MOCVD using AIN as the buffer layer. High light extraction LEDs were prepared by substrate transferring technology in combination with thin-film and flip-chip design. The blue and white 1.1 × 1.1 mm2 LED lamps are measured. The optical powers and external quantum efficiency for silicone encapsulated blue lamp are 546 mW, and 50.3% at forward current of 350 mA, while the photometric light output for a white lamp packaged with standard YAG phosphor is 120.1 lm.
