Abstract:
PROBLEM TO BE SOLVED: To obtain an infrared detector device, exhibiting a high efficiency of transfer from infrared radiation to electrical currents by a semiconductor material. SOLUTION: An infrared detector device 1 is provided with P-N junctions 9 and 10, comprised of a first semiconductor material region 9 doped with rare-earth ions and a second semiconductor material region 10 of the oppositely doped type P. The detector device extends on a substrate 2, including a reflection layer 4 and is provided with a wave guide path 8 formed by protrusions whose range in horizontal direction is demarcated by an oxide a region for protection and containment. At least a part of the wave guide path 8 is formed of a P-N junction and has an end to which light to be detected is supplied. The detector device has electrodes 18 and 13, placed on the side and top of the wave guide path 8 and enables efficient collection of charge carriers produced by optical transfer.
Abstract:
Method for growing carbon nanotubes having a determined chirality, comprising the steps of fragmentation of at least one initial carbon nanotube (30) having a determined chirality with obtainment of at least two portions, or seeds, of carbon nanotube, each one having one free growth end (32); supply of atoms of carbon (33) with autocatalyst addition of the atoms of carbon (33) at the free end (32) of each portion of nanotube (30) to determine an elongation, or growth, of the nanotube (30).
Abstract:
The invention relates to a semiconductor device for electro-optic applications of the type including at least a rare-earth ions doped P/N junction integrated on a semiconductor substrate. This device may be used to obtain laser action in Silicon and comprises a cavity or a waveguide and a coherent light source obtained incorporating the rare-earth ions, and specifically Erbium ions, in the depletion layer of said P/N junction. The junction may be for instance the base-collector region of a bipolar transistor and is reverse biased.