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The silicon-on-insulator (SOI) technology is currently recognized as the most viable silicon photonics platform technology for the integration of photonic components onto a silicon wafer, especially silicon waveguide structures. Although a number of photonic components can be manufactured in the technology, the realization of a silicon-based light source in this platform technology is still problematic. The SOI technology, however, is also one of the important vehicles to integrate nanometer scale CMOS integrated circuits. This work describes the design and characterization of silicon nanowire structures in SOI technology to be implemented as light sources, especially as the source for short-haul optical data communication links. Since the light emission also covers the visible region, micro display applications are also envisaged. Building on our previous work in SOI light sources, pn junctions are manufactured in an array of nanowires for coupling into optical fibers for CMOS optical data communications up to a few hundred meters. Since the photon generation is due to hot electron intraband relaxation processes, the carriers must be excited in a fairly large electric field. This is achieved by placing the pn junction into avalanche breakdown. In an effort to reduce the operating voltage, and at the same time increase the average electron energy, a reach-through device structure is implemented. The average electric field in the pn junction is increased using reach-through, causing the electrons within the junction to be higher. This will increase the short wavelength emission, especially in the visible region. We believe the SOI light sources are fully compatible with modern CMOS technologies based on SOI and may provide such technologies with a much needed light source as part of the circuit designer’s toolkit. Integrating light sources in CMOS ICs will allow capitalizing on its widespread use in electronics.
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