Characterization and Simulations of Long Wavelength Indium Aluminum Gallium Arsenideindium Phosphide Lasers
Characterization and Simulations of Long Wavelength Indium Aluminum Gallium Arsenideindium Phosphide Lasers

Author: Julie Nkanta

Publisher:

Published: 2008

Total Pages: 0

ISBN-13:

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This thesis studies the characterization and simulation of long wavelength indium aluminium gallium arsenide (InAlGaAs) lattice-matched to indium phosphide (InP) diode laser, emitting between 1.648 to 1.7 mum in wavelength. The active region of one laser diode sample consists of six In0.69Ga 0.31As quantum wells (1.0% compressive strain) and seven In0.52 Al0.36Ga0.12As unstrained barriers. The lasers are grown using digital alloy molecular beam epitaxy (MBE). The band diagram analysis shows a large conduction band offset which is typical of InAlGaAs lasers. The geometry-dependent and temperature-dependent measurement as well as the laser optical gain, loss and spectral properties were carried out and comparison done for different ridge widths (1.2 to 2.8mum), cavity lengths (555 to 2200mum) and temperature range between 25 and 70°C. The output power as a function of current characteristics reveals threshold current increase with cavity lengths and ridge widths with thermal roll-off occurring at higher injection currents. The slope efficiency and external differential quantum efficiency increases for the narrowest and widest ridge widths within the same cavity length laser device but decreases with increase in cavity length. The temperature analysis shows longer cavity length lasers exhibit better temperature characteristic than the shorter cavity length laser devices indicating the better thermal stability of the longer cavity lasers. Temperature elevations also caused increase in threshold current and decrease in efficiencies. The temperature distribution shows a higher temperature in the active region than the operating temperature due to self heating of the laser devices in continuous wave operation. The optical spectrum exhibits red-shifting of the emission wavelength with increasing bias current and temperature.

Comprehensive Semiconductor Science and Technology
Comprehensive Semiconductor Science and Technology

Author:

Publisher: Newnes

Published: 2011-01-28

Total Pages: 3572

ISBN-13: 0080932282

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Semiconductors are at the heart of modern living. Almost everything we do, be it work, travel, communication, or entertainment, all depend on some feature of semiconductor technology. Comprehensive Semiconductor Science and Technology, Six Volume Set captures the breadth of this important field, and presents it in a single source to the large audience who study, make, and exploit semiconductors. Previous attempts at this achievement have been abbreviated, and have omitted important topics. Written and Edited by a truly international team of experts, this work delivers an objective yet cohesive global review of the semiconductor world. The work is divided into three sections. The first section is concerned with the fundamental physics of semiconductors, showing how the electronic features and the lattice dynamics change drastically when systems vary from bulk to a low-dimensional structure and further to a nanometer size. Throughout this section there is an emphasis on the full understanding of the underlying physics. The second section deals largely with the transformation of the conceptual framework of solid state physics into devices and systems which require the growth of extremely high purity, nearly defect-free bulk and epitaxial materials. The last section is devoted to exploitation of the knowledge described in the previous sections to highlight the spectrum of devices we see all around us. Provides a comprehensive global picture of the semiconductor world Each of the work's three sections presents a complete description of one aspect of the whole Written and Edited by a truly international team of experts