Characteristics of a GaN-Based Light-Emitting Diode With an Inserted p-GaN/i-InGaN Superlattice Structure

An interesting GaN-based light-emitting diode (LED) with a ten-period i (undoped)-InGaN/p (Mg doped)-GaN (2.5 nm/5 nm) superlattice (SL) structure, inserted between a multiple-quantum well (MQW) structure and a p-GaN layer, is fabricated and studied. This inserted SL can be regarded as a confinement layer of holes to enhance the hole injection efficiency. As compared with a conventional LED device without the SL structure, the studied LED exhibits better current spreading performance and an improved quality. The turn-on voltage, at 20 mA, is decreased from 3.32 to 3.14 V due to the reduced contact resistance as well as the more uniformity of carriers injection. A substantially reduced leakage current (10- 7 to 10- 9 A) and higher endurance of the reverse current pulse are found. The measured output power and external quantum efficiency (EQE) of the studied LED are 13.6 mW and 24.8%. In addition, as compared with the conventional LED without the SL structure, the significant enhancement of 25.4% in output power as well as the increment of 5% in EQE are observed due to the superior current spreading ability and reduction of dislocations offered by the SL structure.

[1]  R. Dupuis,et al.  Characteristics of Green Light-Emitting Diodes Using an InGaN:Mg/GaN:Mg Superlattice as p-Type Hole Injection and Contact Layers , 2008 .

[2]  Stephen J. Sweeney,et al.  The temperature dependence of 1.3- and 1.5-/spl mu/m compressively strained InGaAs(P) MQW semiconductor lasers , 1999 .

[3]  Ashraf Uddin,et al.  Structural and photoluminescence study of thin GaN film grown on silicon substrate by metalorganic chemical vapor deposition , 2007 .

[4]  Influence of AlGaN/GaN superlattice inserted structure on the performance of InGaN/GaN multiple quantum well light emitting diodes , 2007 .

[5]  Cheul-Ro Lee,et al.  High-quality GaN/Si(111) epitaxial layers grown with various Al0.3Ga0.7N/GaN superlattices as intermediate layer by MOCVD , 2003 .

[6]  B. Šantić.  On the hole effective mass and the free hole statistics in wurtzite GaN , 2003 .

[7]  Donghwan Kim,et al.  Low turn-on voltage and series resistance of polarization-induced InGaN-GaN LEDs by using p-InGaN/p-GaN superlattice , 2006, IEEE Photonics Technology Letters.

[8]  Efficient Acceptor Activation in AlxGa1−xN/GaN Doped Superlattices , 2000 .

[9]  E. Fred Schubert,et al.  The origin of the high diode-ideality factors in GaInN/GaN multiple quantum well light-emitting diodes , 2009 .

[10]  Xian-An Cao,et al.  Microstructural origin of leakage current in GaN/InGaN light-emitting diodes , 2004 .

[11]  J. Sheu,et al.  Low-operation voltage of InGaN/GaN light-emitting diodes by using a Mg-doped Al/sub 0.15/Ga/sub 0.85/N/GaN superlattice , 2001, IEEE Electron Device Letters.

[12]  H. Korsch,et al.  Multi-barrier resonant tunnelling for the one-dimensional nonlinear Schrödinger Equation , 2009, 0908.4475.

[13]  Tsung-Han Tsai,et al.  On an AlGaInP-Based Light-Emitting Diode With an ITO Direct Ohmic Contact Structure , 2009, IEEE Electron Device Letters.

[14]  Y. Su,et al.  AlGaInP Light Emitting Diode with a Modulation-Doped Superlattice , 2003 .

[15]  K. Delaney,et al.  Auger recombination rates in nitrides from first principles , 2009, 0904.3559.

[16]  E. F. Schubert,et al.  Current crowding in GaN/InGaN light emitting diodes on insulating substrates , 2001 .

[17]  High Room-Temperature Hole Concentrations above 10 19 cm −3 in Mg-Doped InGaN/GaN Superlattices , 2000 .

[18]  Ja-Soon Jang,et al.  High output power GaN-based light-emitting diodes using an electrically reverse-connected p-Schottky diode and p-InGaN–GaN superlattice , 2008 .

[19]  Jay M. Shah,et al.  Experimental analysis and theoretical model for anomalously high ideality factors (n≫2.0) in AlGaN/GaN p-n junction diodes , 2003 .

[20]  W. Lanford,et al.  Low resistance Ti'Pt'Au ohmic contacts to p-type GaN , 2000 .

[21]  H. Yonezu,et al.  Suppression of threading dislocation generation in highly lattice mismatched heteroepitaxies by strained short-period superlattices , 1993 .

[22]  Ming‐Chung Wu,et al.  Measurement of Junction Temperature in a Nitride Light-Emitting Diode , 2008 .

[23]  Wen-Chau Liu,et al.  Performance investigation of GaN-based light-emitting diodes with tiny misorientation of sapphire substrates. , 2010, Optics express.