Reliability of InGaN laser diodes grown on low dislocation density bulk GaN substrates

We used single crystals of GaN, obtained from high-pressure synthesis, as substrates for Metalorganics Vapor Phase Epitaxy growth of violet and UV laser diodes. The use of high-quality bulk GaN leads to the decrease of the dislocation density to the low level of 105 cm−2, i.e. two orders of magnitude better than typical for the Epitaxial Lateral Overgrowth laser structures fabricated on sapphire. The low density and homogeneous distribution of defects in our structures enables the realization of broad stripe laser diodes. We demonstrate that our laser diodes, having 15 μm wide stripes, are able to emit 1.3-1.9 W per facet (50% reflectivity) in 30 ns long pulses. This result, which is among the best ever reported for nitride lasers, opens the path for the development of a new generation of high power laser diodes.

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LPE Growth of Bulk GaN Crystal by Alkali-Metal Flux Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.600-603.1245 ◽

2008 ◽

Vol 600-603 ◽

pp. 1245-1250 ◽

Cited By ~ 1

Author(s):

Fumio Kawamura ◽

Hidekazu Umeda ◽

Masanori Morishita ◽

Ryohei Gejo ◽

Masaki Tanpo ◽

...

Keyword(s):

Dislocation Density ◽

Secondary Ion Mass Spectrometry ◽

Impurity Content ◽

Single Crystal Substrate ◽

Flux Method ◽

Low Dislocation Density ◽

Bulk Gan ◽

New Apparatus ◽

Metal Flux ◽

Gan Crystal

We succeeded in growing a GaN single crystal substrate with diameter of about two inches using the Na flux method. Our success is due to the development of a new apparatus for growing large GaN single crystals. The crystal grown in this study has a low dislocation density of 2.3×105 (cm-2), The secondary ion mass spectrometry (SIMS) technique demonstrates that the Na element is difficult to be taken in the crystal in both the + and – c directions, resulting in a Na concentration of 4.2 × 1014 (cm-3) in the crystal. Our success in growing a two-inch GaN substrate with a low impurity content and low dislocation density should pave the way for the Na flux method to become a practical application.

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Reliability of AlGaN/GaN high electron mobility transistors on low dislocation density bulk GaN substrate: Implications of surface step edges

Applied Physics Letters ◽

10.1063/1.4829062 ◽

2013 ◽

Vol 103 (19) ◽

pp. 193507 ◽

Cited By ~ 16

Author(s):

N. Killat ◽

M. Montes Bajo ◽

T. Paskova ◽

K. R. Evans ◽

J. Leach ◽

...

Keyword(s):

Dislocation Density ◽

Electron Mobility ◽

High Electron Mobility Transistors ◽

High Electron ◽

High Electron Mobility ◽

Surface Step ◽

Electron Mobility Transistors ◽

Low Dislocation Density ◽

Bulk Gan ◽

Step Edges

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High-Power and Long-Lifetime InGaN Multi-Quantum-Well Laser Diodes Grown on Low-Dislocation-Density GaN Substrates

Japanese Journal of Applied Physics ◽

10.1143/jjap.39.l647 ◽

2000 ◽

Vol 39 (Part 2, No. 7A) ◽

pp. L647-L650 ◽

Cited By ~ 181

Author(s):

Shin-ichi Nagahama ◽

Naruhito Iwasa ◽

Masayuki Senoh ◽

Toshio Matsushita ◽

Yasunobu Sugimoto ◽

...

Keyword(s):

Dislocation Density ◽

Quantum Well ◽

High Power ◽

Laser Diodes ◽

Quantum Well Laser ◽

Low Dislocation Density ◽

Long Lifetime ◽

Multi Quantum Well

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Growth of Bulk GaN with Low Dislocation Density by the Ammonothermal Method Using Polycrystalline GaN Nutrient

Japanese Journal of Applied Physics ◽

10.1143/jjap.46.l525 ◽

2007 ◽

Vol 46 (No. 22) ◽

pp. L525-L527 ◽

Cited By ~ 11

Author(s):

Tadao Hashimoto ◽

Feng Wu ◽

James S. Speck ◽

Shuji Nakamura

Keyword(s):

Dislocation Density ◽

Low Dislocation Density ◽

Bulk Gan

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Low stress and low dislocation density AlGaAs/GaAs laser diodes fabricated on Si substrates

13th IEEE International Semiconductor Laser Conference ◽

10.1109/islc.1992.763568 ◽

2005 ◽

Cited By ~ 1

Author(s):

N. Wada ◽

S. Yosfumi ◽

S. Sakai ◽

M. Fukui

Keyword(s):

Dislocation Density ◽

Laser Diodes ◽

Si Substrates ◽

Low Dislocation Density ◽

Gaas Laser

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400-nm Band AlGaInN-Based High Power Laser Diodes

MRS Proceedings ◽

10.1557/proc-693-i4.1.1 ◽

2001 ◽

Vol 693 ◽

Cited By ~ 3

Author(s):

Takeharu Asano ◽

Motonobu Takeya ◽

Tsuyoshi Tojyo ◽

Shinro Ikeda ◽

Takashi Mizuno ◽

...

Keyword(s):

Dislocation Density ◽

Active Layer ◽

High Power ◽

Continuous Wave ◽

Laser Diodes ◽

Epitaxial Lateral Overgrowth ◽

Direct Result ◽

Electron Blocking Layer ◽

Low Dislocation Density ◽

Operating Current

AbstractHigh-power AlGaInN-based laser diodes (LDs) operating with high reliability in the 400-nm band have been successfully fabricated using a high-productivity process. Epitaxial lateral overgrowth (ELO) over a 10-m m region was employed to obtain a broad growth area with low dislocation density, and the thickness of the ELO-GaN layer was limited to approximately 5 m in order to minimize wafer bending. These techniques allow for the easy and reproducible alignment of the laser stripe on the region of low dislocation density. The insertion of a GaInN interlayer between the active layer and the AlGaN electron blocking layer was effective for reducing the strain between these two layers, resulting in homogeneous luminescence from the active layer and lower operating current. A mean time to failure of 15000 h under 30-mW continuous-wave operation at 60°C was realized as a direct result of the lower operating current. Productivity was remarkably improved by performing epitaxial growth on a 3-inch substrate. Highly uniform laser wafers were successfully fabricated by achieving minimal temperature variation (1000 ±7°C) over the 3-inch substrate. The resultant laser structures varied in thickness by only ±5%, and the photoluminescence wavelength was consistent within ±2.5 nm over the entire 3-inch substrate. The average threshold current of 550 LDs selected from a fourth wafer was 32.7 mA, with small standard deviation of 3.2 mA.

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