Improved Output Power of Nitride-Based Light-Emitting Diodes With Convex-Patterned Sapphire Substrates

Nitride-based light-emitting diodes (LEDs) grown on different convex-patterned sapphire substrates are proposed and fabricated. The electrical and optical properties of these LEDs are discussed in detail. It is found that the LED with a ball-shape patterned sapphire substrate has the best crystalline quality and I-V characteristic. On the other hand, on reducing total internal reflection, the LED with hexagonal-shape patterned sapphire substrate (HPSS) has the best performance on output power and external quantum efficiency. In comparison to the LED without patterned substrate, the LED with HPSS has 175% and 165% enhancement on output power and external quantum efficiency, respectively.

[1]  Jinn-Kong Sheu,et al.  Enhanced efficiency of GaN-based light-emitting diodes with periodic textured Ga-doped ZnO transparent contact layer , 2007 .

[2]  Yan-Kuin Su,et al.  Pattern-size dependence of characteristics of nitride-based LEDs grown on patterned sapphire substrates , 2009 .

[4]  R. Horng,et al.  Near-Ultraviolet InGaN/GaN Light-Emitting Diodes Grown on Patterned Sapphire Substrates , 2005 .

[5]  C.L. Lin,et al.  Enhanced Output Power of GaN-Based LEDs With Nano-Patterned Sapphire Substrates , 2008, IEEE Photonics Technology Letters.

[6]  M. L. Lee,et al.  InGaN light-emitting diodes with naturally formed truncated micropyramids on top surface , 2006 .

[7]  Yeong-Her Wang,et al.  Enhancement of the light output performance for GaN-based light-emitting diodes by bottom pillar structure , 2007 .

[8]  Y. Hsu,et al.  InGaN-GaN MQW LEDs with Si treatment , 2005, IEEE Photonics Technology Letters.

[9]  Hao-Chung Kuo,et al.  High Brightness GaN-Based Light-Emitting Diodes , 2007, Journal of Display Technology.

[10]  Gustaaf Borghs,et al.  Light-emitting diodes with 31% external quantum efficiency by outcoupling of lateral waveguide modes , 1999 .

[11]  J. K. Sheua.  InGaN light-emitting diodes with naturally formed truncated micropyramids on top surface , 2006 .

[12]  Chih-Chiang Kao,et al.  Light-output enhancement in a nitride-based light-emitting diode with 22° undercut sidewalls , 2005, IEEE Photonics Technology Letters.

[13]  S. Lee.  Study of photon extraction efficiency in InGaN light-emitting diodes depending on chip structures and chip-mount schemes , 2006 .

[14]  Dong-Sing Wuu,et al.  Improved Light Extraction of Nitride-Based Flip-Chip Light-Emitting Diodes Via Sapphire Shaping and Texturing , 2006, IEEE Photonics Technology Letters.

[15]  Shyi-Ming Pan,et al.  Improvement of InGaN-GaN light-emitting diodes with surface-textured indium-tin-oxide transparent ohmic contacts , 2003, IEEE Photonics Technology Letters.

[16]  S.J. Chang,et al.  Nitride-Based High-Power Flip-Chip LED With Double-Side Patterned Sapphire Substrate , 2007, IEEE Photonics Technology Letters.

[17]  W. Wang,et al.  Enhanced output power of near-ultraviolet InGaN-GaN LEDs grown on patterned sapphire substrates , 2005, IEEE Photonics Technology Letters.

[18]  InGaN/GaN light emitting diodes with Ni/Au mesh p-contacts , 2005 .

[19]  E. Suh,et al.  GaN-Based Light-Emitting Diodes on Micro-Lens Patterned Sapphire Substrate , 2008 .

[20]  Y. J. Sung,et al.  Refractive sapphire microlenses fabricated by chlorine-based inductively coupled plasma etching. , 2001, Applied optics.

[21]  Ching-Cherng Sun,et al.  Light extraction analysis of GaN-based light-emitting diodes with surface texture and/or patterned substrate. , 2007, Optics express.

[22]  Chia-Feng Lin,et al.  Enhanced light output in nitride-based light-emitting diodes by roughening the mesa sidewall , 2005 .

[23]  Jinsub Park,et al.  Improvement of luminous intensity of InGaN light emitting diodes grown on hemispherical patterned sapphire , 2006 .

[24]  Takashi Mukai,et al.  InGaN-Based Near-Ultraviolet and Blue-Light-Emitting Diodes with High External Quantum Efficiency Using a Patterned Sapphire Substrate and a Mesh Electrode , 2002 .