InGaN Laser Diodes with Etched Facets for Photonic Integrated Circuit Applications (original) (raw)

Laser Scribing for Facet Fabrication of InGaN MQW Diode Lasers on Sapphire Substrates

IEEE Photonics Technology Letters, 2010

In this letter, a novel method for the fabrication of high-quality facets for III-nitride lasers grown on-plane sapphire substrates as well as on GaN substrates is presented. Based on a laser scribing process gain-guided laser diodes with smooth facets were fabricated, which showed threshold current densities of 6.5 kA cm 2 at an emission wavelength of 405 nm under pulsed operation.

Optimization of InGaN Laser Diodes Based on Numerical Simulations

Acta Physica Polonica A, 2016

Simulations of blue and green laser diodes with InGaN quantum wells are presented. In this study, a particular emphasis on efficiency and optical power of the structures was placed. Effect of the aluminum content in an electron blocking layer on the electron overflow and efficiency is discussed. Substantial decrease of efficiency of laser diodes is reported for low aluminum levels. It is also shown that polarization charges existing in AlInGaN heterostructures grown on GaN polar direction and low ionization degree of magnesium acceptors lead to high resistance of these devices. These effects hinder the carriers from reaching an active region and consequently they impose high operating voltages.

CW Operation of InGaN MQW Laser Diodes

physica status solidi (a), 2000

The performance characteristic of continuous-wave (cw) InGaN multiple-quantum-well (MQW) laser diodes with optimized design parameters is reported. Room temperature, cw operation of InGaN MQW laser diodes was demonstrated with threshold current densities as low as 7 kA/cm 2 and emission wavelength near 400 nm. For 2 mm  300 mm ridge waveguide nitride laser with reflection-coated mirrors cw threshold currents of 60 mA have been obtained. CW operation was observed up to temperatures of 60 C. The transverse and lateral optical modes of nitride lasers, toward optimization of the layer structure and ridge waveguide parameters have been analyzed. Incorporation of a thick, superlattice n-cladding layer led to a considerable improvement in the transverse beam quality. Thermal modeling indicated the importance of lowering the diode voltage and efficient heat dissipation; and specifically, the benefit of thinning the sapphire substrate for achieving room temperature cw operation.

Characterization of InGaN/AlGaN multiple-quantum-well laser diodes

Physics and Simulation of Optoelectronic Devices VII, 1999

This paper discusses the design and characteristics of 111-nitride based multi-quantum well (MQW) laser diodes grown on a-as well as c-plane sapphire substrates by metal organic chemical vapor deposition (MOCVD). Threshold current densities as low as 4.8 kA/cm2 have been observed on devices with CAIBE etched mirrors and a SiO2ITiO2 high reflective coating on both facets. The lowest threshold currents obtained were around 55 mA (Uth= 9.5V) for 3.tm 300Mm ridge-waveguide laser diodes devices which allow room temperature pulsed operation up to 70% duty cycle (devices mounted p-side up). From cavity length studies the distributed loss in our structures was determined to be of the order of 35-45 cm1. At threshold this corresponds to a maximum modal gain of about I 10 cm1 or a material gain of about 2200 cm1.

InGaN/GaN Laser Diodes and their Applications

2018 20th International Conference on Transparent Optical Networks (ICTON), 2018

Gallium nitride (GaN) laser diodes are becoming popular sources not only for lighting but for applications ranging from communications to quantum. This paper presents the use of a commercial, off-the-shelf laser diode, with an emission wavelength of 450 nm, for visible light communication, both in free space and for underwater scenarios. Data rates up to 15 Gbit/s have been achieved by making use of orthogonal frequency division multiplexing (OFDM). In addition, distributed feedback (DFB) lasers have been realised emitting at a single wavelength which lend themselves towards applications where high spectral purity is crucial such as atomic clocks or filtered free space transmission systems. These devices have the grating structure etched into the sidewall of the ridge and work is ongoing to measure the linewidth of these lasers with the intended application of cooling Sr+ ions.

Low dislocation density, high power InGaN laser diodes

MRS Internet Journal of Nitride Semiconductor Research, 2004

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.

Characteristics of InGaN-AlGaN multiple-quantum-well laser diodes

1998

Abstract We demonstrate room-temperature pulsed current-injected operation of InGaAlN heterostructure laser diodes with mirrors fabricated by chemically assisted ion beam etching. The multiple-quantum-well devices were grown by organometallic vapor phase epitaxy on c-face sapphire substrates. The emission wavelengths of the gain-guided laser diodes were in the range from 419 to 432 nm. The lowest threshold current density obtained was 20 kA/cm 2 with maximum output powers of 50 mW.

InGaN Double Heterostructure (DH) Laser Diode Performance and Optimization

The laser performances of the blue DH InGaN laser diode (LD) structures have been numerically investigated by using ISE TCAD software. We have selected In0.13Ga0.87N as the active layer with thickness of 15 nm sandwiched between two layers of 70 nm Al0.15Ga0.85N separate confinement heterostructure (SCH). The output power with a value of 84 mW was obtained at a threshold current of 110 mA and with peak emission wavelength at 426 nm. We investigated the effect of graded Al0.15Ga0.85N layer on the output power and threshold current of our laser diode structure. The enhancement in the output power and a decrease in the threshold current resulting from graded layers effect were observed.

Characteristic of InGaN/GaN Laser Diode Grown by a Multi-Wafer MOCVD System

MRS Internet Journal of Nitride Semiconductor Research, 1999

InGaN/GaN multi-quantum well (MQW) laser diodes (LDs) were grown on c-plane sapphire substrates using a multi-wafer MOCVD system. The threshold current for pulsed lasing was 1.6 A for a gain-guided laser diode with a stripe of 10 × 800 μm2. The threshold current density was 20.3 kA cm−2 and the threshold voltage was 16.5 V. The optical power ratio of transverse electric mode to transverse magnetic mode was found to be greater than 50. The characteristic temperature measured from the plot of threshold current versus measurement temperature was between 130 and 150K.