Effect Of AlGaN/GaN Strained Layer Superlattice Period On InGaN MQW Laser Diodes

AlGaN/GaN strained layer superlattices have been employed in the cladding layers of InGaN multi-quantum well laser diodes grown by metalorganic chemical vapor deposition (MOCVD). Superlattices have been investigated for strain relief of the cladding layer, as well as an enhanced hole concentration, which is more than ten times the value obtained for bulk AlGaN films. Laser diodes with strained layer superlattices as cladding layers were shown to have superior structural and electrical properties compared to laser diodes with bulk AlGaN cladding layers. As the period of the strained layer superlattices is decreased, the threshold voltage, as well as the threshold current density, is decreased. The resistance to vertical conduction through p-type superlattices with increasing superlattice period is not offset by the increase in hole concentration for increasing superlattice spacing, resulting in higher voltages.

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Effect of AlGaN/GaN Strained Layer Superlattice Period on InGaN MQW Laser Diodes

MRS Proceedings ◽

10.1557/proc-595-f99w1.4 ◽

1999 ◽

Vol 595 ◽

Cited By ~ 1

Author(s):

Monica Hansen ◽

Amber C. Abare ◽

Peter Kozodoy ◽

Thomas M. Katona ◽

Michael D. Craven ◽

...

Keyword(s):

Hole Concentration ◽

Laser Diodes ◽

Chemical Vapor ◽

Threshold Current ◽

Threshold Current Density ◽

Strained Layer ◽

Strained Layer Superlattice ◽

Strained Layer Superlattices ◽

Cladding Layers ◽

Superlattice Period

AbstractAlGaN/GaN strained layer superlattices have been employed in the cladding layers of InGaN multi-quantum well laser diodes grown by metalorganic chemical vapor deposition (MOCVD). Superlattices have been investigated for strain relief of the cladding layer, as well as an enhanced hole concentration, which is more than ten times the value obtained for bulk AlGaN films. Laser diodes with strained layer superlattices as cladding layers were shown to have superior structural and electrical properties compared to laser diodes with bulk AlGaN cladding layers. As the period of the strained layer superlattices is decreased, the threshold voltage, as well as the threshold current density, is decreased. The resistance to vertical conduction through p-type superlattices with increasing superlattice period is not offset by the increase in hole concentration for increasing superlattice spacing, resulting in higher voltages.

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Current spreading in AlGaN:Mg cladding layers of laser structures

MRS Proceedings ◽

10.1557/proc-693-i11.26.1 ◽

2001 ◽

Vol 693 ◽

Cited By ~ 1

Author(s):

Stephan Figge ◽

Tim Böttcher ◽

Christoph Zellweger ◽

Marc Ilegems ◽

Detlef Hommel

Keyword(s):

Laser Diodes ◽

Current Spreading ◽

Strained Layer ◽

Current Path ◽

Current Voltage ◽

Strained Layer Superlattice ◽

Strained Layer Superlattices ◽

Cladding Layers ◽

Significant Spread ◽

Mg Doped

AbstractThe consequences of the anisotropic resistance in AlGaN/GaN strained layer superlattices for the operation of laser diodes were studied for structures driven in LED mode. A series of laser structures containing different Mg-doped AlGaN bulk and AlGaN/GaN strained layer superlattice cladding layers was compared to estimate the current spreading in the cladding due to the formation of 2D-hole gases. Current-voltage measurements revealed a significant spread of the current path in the superlattices, whereas no spreading was seen for the bulk cladding. In contrast to this, investigations of the electroluminescence showed no significant differences.

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The Growth of InAsSb/InGaAs Strained-Layer Superlattices by Metal-Organic Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-325-493 ◽

1993 ◽

Vol 325 ◽

Cited By ~ 3

Author(s):

R. M. Biefeld ◽

K. C. Baucom ◽

S. R. Kurtz ◽

D. M. Follstaedt

Keyword(s):

Chemical Vapor Deposition ◽

Thermodynamic Model ◽

Vapor Deposition ◽

Chemical Vapor ◽

Organic Chemical ◽

Strained Layer ◽

Strained Layer Superlattice ◽

Metal Organic ◽

Strained Layer Superlattices ◽

Organic Chemical Vapor Deposition

AbstractWe have grown InAsl-xSbx/Inl-yGayAs strained-layer superlattice (SLS) semiconductors lattice matched to InAs using a variety of conditions by metal-organic chemical vapor deposition. The V/III ratio was varied from 2.5 to 10 at a temperature of 475 °C, at pressures of 200 to 660 torr and growth rates of 3 - 5 A/s and layer thicknesses ranging from 55 to 152 Å. The composition of the InAsSb ternary can be predicted from the input gas molar flow rates using a thermodynamic model. At lower temperatures, the thermodynamic model must be modified to take account of the incomplete decomposition of arsine and trimethylantimony. Diodes have been prepared using Zn as the p-type dopant and undoped SLS as the n-type material. The diode was found to emit at 3.56 μm. These layers have been characterized by optical microscopy, SIMS, x-ray diffraction, and transmission electron diffraction. The optical properties of these SLS's were determined by infrared photoluminescence and absorption measurements.

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