Silicon-based lasers

Figure 7.5. Experimental configuration for the DIOS-MS experiments, (a) Four porous silicon plates are placed on a MALDI plate. Each of the porous silicon plates contains photopattemed spots or grids prepared through illumination of -type silicon with a 300-S tungsten filament through a mask and an 50 reducing lens, (b) Ibe silicon-based laser desorption/ionization process, in which the sample is placed on the porous silicon plate and allowed to dry, followed by laser-induced desorption/ionization mass spectrometry, (c) Cross section of porous silicon, and the surface functionalities after hydrosilylation R represents phenyl or alkyl chains. (Reproduced with permission from Wei, J. Buriak, J. Siuzdak, G. Desorption/ionization mass spectrometry on porous silicon. Nature 1999, 399, 243-246.)...

During the course of the last century, it was realized that many properties of solids are controlled not so much by the chemical composition or the chemical bonds linking the constituent atoms in the crystal but by faults or defects in the structure. Over the course of time the subject has, if anything, increased in importance. Indeed, there is no aspect of the physics and chemistry of solids that is not decisively influenced by the defects that occur in the material under consideration. The whole of the modem silicon-based computer industry is founded upon the introduction of precise amounts of specific impurities into extremely pure crystals. Solid-state lasers function because of the activity of impurity atoms. Battery science, solid oxide fuel cells, hydrogen storage, displays, all rest upon an understanding of defects in the solid matrix. 

The modem silicon-based microelectronics led to the miniaturization of electronic devices. However, delays caused by metallic intercoimec-tions became a bottleneck for the improvement of their performances. One possible solution of this problem is to use optical intercoimections for the transfer of information, and, therefore, silicon compatible materials and devices that are able to generate, guide, amplify, switch, modulate, and detect light are needed. Rare earth silicates with luminescent rare earths and compatibility with silicon may be a good choice for these applications (Miritello et al., 2007). Miritello et al. presented the study on nanocrystalline erbium silicate thin films fabricated on silicon/silica substrates. The obtained films exhibit strong photoluminescence emission around 1540 nm with room temperature excitation by 488 ran Ar laser. 

Tellurium is a narrow band gap semiconductor and is a component of different important binary and ternary semiconductors such as CdTe, PbTe, Cdi.xHgxTe, Pbi.xSnxTe, etc. Heterostructures based on these semiconductors and Si are used for IR detectors, laser diodes, etc. However, little attention has been paid to the features of individual components deposition in electrochemical studies with tellurides. The aim of this work was to investigate cathodic nucleation of Te nanoparticles on n-Si. We also used nanoporous SiO2 layer on Si as a template for Te nanoparticles deposition. Nanopores in SiO2/Si are of particular interest for silicon-based electronics and nanoelectronics [1]. 

Unlike IR spectroscopy where nowadays FT instrumentation is solely used, in Raman spectroscopy both conventional dispersive and FT techniques have their applications, the choice being governed by several factors. The two techniques differ significantly in several performance criteria, and neither one is best for all applications. Contemporary dispersive Raman spectrometers are often equipped with silicon-based charge coupled device (CCD) multichannel detector systems, and laser sources with operating wavelength in the ultraviolet, visible or near-infrared region are employed. In FT Raman spectroscopy, the excitation is provided exclusively by near-infrared lasers (1064 nm or 780 nm). 

The paint or ink used must be conductive to laser processing. Standard paints and inks are not predictable nor controllable when exposed to the laser output. The inks bum easily and can mix the underlying plastic while in the molten liquid state. Laser compatible inks are mixed with a silicone based material reflective to the laser output thereby reducing the inks light absorption and rate of thermal reaction. Paints must be suitable for high temperature processing and be free of any contaminants that may absorb the laser wavelength and speed up the thermal rise. 

The interest in BeSe originates from the fact that ternary BeZnSe and quaternary BeMgZnSe alloys can be lattice-matched to silicon substrates and can also be used as base materials for blue-green-emitting ZnSe-based laser diodes grown on GaAs. The ternary alloy has a band gap of approximately 4 eV if lattice-matched to silicon. 

Ben Rabha M, Dimassi W, Bonaicha M, Ezzaoia H, Bessais B (2009) Laser-beam-induced current mapping evolution of porous silicon-based passivation in polycrystalline silicon solar cells. Sol Energy 83 721-725... 

Ruminski AM, Secret E, Sailor MJ (2008) Chemical sensors based on resonant diffraction gratings made of porous silicon imprinted with a silicone polymer. In Canham LT et al (eds) Porous semiconductor science and technology, Mallorca pp 113-114 Ryckman JD, Liscidini M, Sipe JE, Weiss SM (2010a) Porous sihcon structures for low-cost diffraction-based biosensing. Appl Phys Lett 96(17) 171103 Ryckman JD, Liscidini M, Sipe JE, Weiss SM (2010b) Diffraction based biosensing with porous silicon. In Lasers and Electro-Optics (CLEO) and Quantum Electronics and Laser Science conference (QELS), 2010 conference on Lasers and Electro-Optics, San Jose, Cabfomia United States, pp 1-2... 

Yamamoto N, Takai H (2001) Formation mechanism of silicon based luminescence material using a photo ehemieal etching method. Thin Solid Films 388 138-142 Zhang Z, Lemer MM, Alekel T 111, Keszler DA (1993) Formation of a photoluminescent surface on n-Si by irradiation without an externally applied potential. J Eleetroehem Soc 140 L97-L98 Zheng HY, Chai JC, Lam YC, Zhu H (2005) Formation of porous struetures on Si surface by laser-assisted etehing. Surf Rev Lett 12 351-354... 

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