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Key Words: Semiconductor Compound, Semiconductor, Semiconductor Laser, Gallium Nitride blue laser History and developmentGallium Nitride blue laser knowhow started at Cornell University with the formation of laser facets by utilizing Chemically Assisted Ion Beam Etching (CAIBE) process. Motivation behind this knowhow and its development thereafter to the current, encompassed prospects for profits and foreseeable economic benefits especially for the society (Jang et al 64730X-2). The latter aspect entailed finding economical means of lighting and storage of information; though before blue lasers there were red lasers (Watkins).
Initially, the advancement of this knowhow posed an impossible task to then experts prompting numerous companies and other users continue relying on red lasers. This is because of the task involved in the crystallizing semiconductor compound supposed to produce blue light (Watkins). The other major task was because of the elements, which the experts intended to use in fabricating blue lasers. These comprised of elements occupying the right extreme end of a periodic table, which are hard to crystallize (Group VIII).
This is because of their strong bonding characteristics though experts managed to do so with the aid of trial and error approaches. This gave rise to the first innovation and fabrication of ZnSe semiconductor laser in 1993. The fabricated product was capable operating in a continuous-wave at room-temperature, hence disapproving notion; the attainment or realization of the venture was impossible. In 1996, Sony managed to emerge with a continuous Oscillation product of the same semiconductor that operated for a duration of 1000 hours, hence bringing the knowhow’s development within reach (“Sony”).
This is especially to the commercial corporations, for instance, Nichia, which recorded exportations of approximately 2 Million GaN LEDs on monthly basis in 1996. Since then to date, the knowhow keeps on developing due to high preference of its products in the market and economic benefits associated with the usage (Jang et al 64730X-1). For example, optical storage devices like Bluray and HD-DVD players that have a wavelength of 405nm (Jang et al 64730X-1). GaN LDs market has also extended in other varied but incoming technological gadgets, for instance, portable laser projectors (Jang et al 64730X-1).
Recently, in 2003 Sony managed to fabricate blue violet semiconductor laser meant for use in consumer electronic gadgets, hence acting as a breakthrough in boosting their technological knowhow. This advancement prompted Sony Corporation to launch the ever fabricated world’s first BD recorder (BDZ-S77) (“Sony”). In addition, there are foreseeable prospects of high advanced gadgets after integrating this knowhow in future with other gadgets. Currently, experts contend there is an unequaled interest towards fabricating of inexpensive 405nm-emitting GaN based lasers (Behfar et al).
These will be for the incoming DVD application generation, which will boost creativity in making high quality and efficient electronic products (Behfar et al). Since, there will be continuous expedition of intending to produce nicer and even finer components meant to compete in the market (Behfar et al). Characteristics GaN blue lasers have long lifetime compared to the former gadgets that used to serve a similar purpose (Jang et al 64730X-9). Since, their duration under room conditions are capable of having a lifetime of approximately 10000 hours before exhibiting any malfunctions or slowing in terms of output (Jang et al 64730X-9).
In addition, they possess high power recording, which is a COD level of 334mW (under ordinary conditions) (Jang et al 64730X-9). Therefore, this makes them effective in their respective areas of application or in gadgets that normally use them for better end user’s services (Jang et al 64730X-9). However, there are no observable characteristic discrepancies between blue LDs on LEO-GaN/sapphire and that of GaN substrate (Jang et al 64730X-2). This is because of the large refractive index evident between these two aspects that normally hinder vertical ripple direction from forming (Jang et al 64730X-2).
Jang et al in their study cite this phenomenon occurred due to the use of blue LDs in the experiment that were optically confined using cladding layers (Jang et al 64730X-3). Blue-green LDs exhibit poor performance in their operation compared to their already expected outcomes, which they out to give. Jang et al in their study contend this poor performance emanates from piezo-electric’s effect responsible for the mismatch of lattice especially along the C-axis of GaN (Jang et al 64730X-3). However, solution to this predicament encompasses regulating QWs thickness or utilizing semi-polar substrates (Jang et al 64730X-10).
The poor performance also emanates from in-fluctuation caused by lattice’s mismatch and in-solubility limit (Jang et al 64730X-10). Therefore, these characteristics and other varied operating modes of blue-green LDs signify there is need for meticulous research. This is to ensure experts are capable of comprehending diverse aspects regarding blue LDs and how to resolve inherent predicaments with the intention of producing efficient products. Work Cited Behfar, A. A., Green, M. R., Hwang, J.
, Morrow, A. J., Schremer, A. T. & Stagarescu, C. B. Progress in Etched Facet Technology for GaN and Blue Lasers. BinOptics Corporatio. n.d. Web. 22nd April 2013. Jang, T., Nam, O. H., Ha, K. H., Lee, S. N., Son, J. K., Ryu, H. Y., Kim, K. S. Paek, H. S., Sung, Y. J. Sung, H. G., Chae, S. H., Kim, Y. H. & Park, Y. Recent Achievements of AlInGaN Based Laser Diodes in Blue and Green Wavelength. Photonics PRJ. Team, Samsung Advanced Institute of Technology. 6473. 64730X. (2007): 1-11. Sony. Technology. 2013. Web.
22nd April 2013. Watkins, Thayer. A Blue Light Gallium Nitride Laser Diode. San Jose State University. n.d. Web. 22nd April 2013
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