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The performance of modern integrated Complementary Metal-Oxide-Semiconductor(CMOS)chips is increasingly limited by the long metal wires instead of the CMOS transistors [1].In the past decades,replacing the long metal wires with optical fibers has been the trend for long distance and high volume communications among continentals,cities and even computers.This trend will inevitably come to a single microchip as the communication bandwidth further increases,which requires integrating optical fibers with the existing silicon-based CMOS transistors on the same chip.However,the energy of photons at telecommunication wavelengths is lower than the bandgap of silicon,resulting in negligible absorption in silicon at these wavelengths.A Si photodetector at communication wavelengths seems unlikely but is the key to this technology advance.Here,we employ a pair of plasmonic antennas to focus light into a nanogap where a Silicon Nanowire(SiNW)is located.The antenna pair,also serving as the two electrodes for the SiNW,consists of two 90°fans of concentric gratings that are designed to resonate at telecommunication wavelengths.The simulation results show that the near field intensity is enhanced over 5 orders of magnitude in the nanogap.The dramatically enhanced field intensity will significantly increase the probability of generating electron-hole pairs in the SiNW by absorbing two photons of communication wavelengths.Indeed,the silicon nanowire shows a responsivity of 0.01A/W at the wavelength of 1310 nm,which is impressive considering that the photon energy at this wavelength is lower than the energy bandgap of Si.As the next step,the nanowire will be designed to be a phototransistor that can further amplify the photocurrent.Successful development of this type of silicon photodetectors will be a milestone for next generation CMOS technology.