Abstract: In one aspect, pixel architectures for employment in photodetector apparatus and systems are described herein. A pixel, in some embodiments, comprises a silicon substrate, and one more dielectric layers over the substrate. The dielectric layers, for example, can comprise silica (SiO2) and/or other suitable dielectric material(s). A photoactive region resides within the one or more dielectric layers, the photoactive region comprising a heterojunction formed of a first Group IVA semiconductor alloy epitaxially extending from an aperture passing through the one or more dielectric layers to the silicon substrate, and a second Group IVA semiconductor alloy extending epitaxially from the first Group IVA semiconductor alloy.

Abstract: A wheelchair stand may include a base; a vertical support bar extending upward from the base; an upper bar extending transversely from the vertical support bar and spaced vertically away from the base; a hanger supported by the upper bar and spaced away from the vertical support bar; and a strap supported by the hanger. A method of maintaining a wheelchair may include: a) moving the wheelchair to a position below a hanger; b) positioning a strap below the wheelchair; c) connecting the strap to opposite ends of the hanger; and d) shortening the strap to raise the wheelchair.

Abstract: A wheelchair stand may include a base; a vertical support bar extending upward from the base; an upper bar extending transversely from the vertical support bar and spaced vertically away from the base; a hanger supported by the upper bar and spaced away from the vertical support bar; and a strap supported by the hanger. A method of maintaining a wheelchair may include: a) moving the wheelchair to a position below a hanger; b) positioning a strap below the wheelchair; c) connecting the strap to opposite ends of the hanger; and d) shortening the strap to raise the wheelchair.

Abstract: In accordance with the invention, an improved image sensor comprises an array of germanium photosensitive elements integrated with a silicon substrate and integrated with silicon readout circuits. The silicon transistors are formed first on a silicon substrate, using well known silicon wafer fabrication techniques. The germanium elements are subsequently formed overlying the silicon by epitaxial growth. The germanium elements are advantageously grown within surface openings of a dielectric cladding. Wafer fabrication techniques are applied to the elements to form isolated germanium photodiodes. Since temperatures needed for germanium processing are lower than those for silicon processing, the formation of the germanium devices need not affect the previously formed silicon devices. Insulating and metallic layers are then deposited and patterned to interconnect the silicon devices and to connect the germanium devices to the silicon circuits.

Abstract: In accordance with the invention, an improved image sensor includes an array of germanium photosensitive elements integrated with a silicon substrate and integrated with silicon readout circuits. The silicon transistors are formed first on a silicon substrate, using well known silicon wafer fabrication techniques. The germanium elements are subsequently formed overlying the silicon by epitaxial growth. The germanium elements are advantageously grown within surface openings of a dielectric cladding. Wafer fabrication techniques are applied to the elements to form isolated germanium photodiodes. Since temperatures needed for germanium processing are lower than those for silicon processing, the formation of the germanium devices need not affect the previously formed silicon devices. Insulating and metallic layers are then deposited and patterned to interconnect the silicon devices and to connect the germanium devices to the silicon circuits.

Abstract: In accordance with the invention, an improved image sensor comprises an array of germanium photosensitive elements integrated with a silicon substrate and integrated with silicon readout circuits. The silicon transistors are formed first on a silicon substrate, using well known silicon wafer fabrication techniques. The germanium elements are subsequently formed overlying the silicon by epitaxial growth. The germanium elements are advantageously grown within surface openings of a dielectric cladding. Wafer fabrication techniques are applied to the elements to form isolated germanium photodiodes. Since temperatures needed for germanium processing are lower than those for silicon processing, the formation of the germanium devices need not affect the previously formed silicon devices. Insulating and metallic layers are then deposited and patterned to interconnect the silicon devices and to connect the germanium devices to the silicon circuits.

Abstract: A photodetector is formed from a body of semiconductor material substantially surrounded by dielectric surfaces. A passivation process is applied to at least one surface to reduce the rate of carrier generation and recombination on that surface. Photocurrent is read out from at least one electrical contact, which is formed on a doped region whose surface lies entirely on a passivated surface. Unwanted leakage current from un-passivated surfaces is reduced through one of the following methods: (a) The un-passivated surface is separated from the photo-collecting contact by at least two junctions; (b) The un-passivated surface is doped to a very high level, at least equal to the conduction band or valence band density of states of the semiconductor; (c) An accumulation or inversion layer is formed on the un-passivated surface by the application of an electric field.

Abstract: Optical imaging structures and methods are disclosed. One structure may be implemented as an imaging pixel having multiple photodetectors. The photodetectors may detect different wavelengths of incident radiation, and may be operated simultaneously or at separate times. An imager may include an imaging array of pixels of the type described. Methods of operating such structures are also described.

Abstract: In accordance with the invention, an improved image sensor includes an array of germanium photosensitive elements integrated with a silicon substrate and integrated with silicon readout circuits. The silicon transistors are formed first on a silicon substrate, using well known silicon wafer fabrication techniques. The germanium elements are subsequently formed overlying the silicon by epitaxial growth. The germanium elements are advantageously grown within surface openings of a dielectric cladding. Wafer fabrication techniques are applied to the elements to form isolated germanium photodiodes. Since temperatures needed for germanium processing are lower than those for silicon processing, the formation of the germanium devices need not affect the previously formed silicon devices. Insulating and metallic layers are then deposited and patterned to interconnect the silicon devices and to connect the germanium devices to the silicon circuits.

Abstract: Imaging arrays comprising at least two different imaging pixel types are described. The different imaging pixel types may differ in their light sensitivities and/or light saturation levels. Methods of processing the output signals of the imaging arrays are also described, and may produce images having a greater dynamic range than would result from an imaging array comprising only one of the at least two different imaging pixel types.

Abstract: Imagers, pixels, and methods of using the same are disclosed for imaging in various spectra, such as visible, near infrared (IR), and short wavelength IR (SWIR). The imager may have an imaging array having pixels of different types. The different types of pixels may detect different ranges of wavelengths in the IR, or the SWIR, spectra. The pixels may include a filter which blocks some wavelengths of radiation in the IR spectrum while passing other wavelengths. The filter may be formed of a semiconductor material, and therefore may be easily integrated with a CMOS pixel using conventional CMOS processing techniques.

Abstract: Imagers, pixels, and methods of using the same are disclosed for imaging in various spectra, such as visible, near infrared (IR), and short wavelength IR (SWIR). The imager may have an imaging array having pixels of different types. The different types of pixels may detect different ranges of wavelengths in the IR, or the SWIR, spectra. The pixels may include a filter which blocks some wavelengths of radiation in the IR spectrum while passing other wavelengths. The filter may be formed of a semiconductor material, and therefore may be easily integrated with a CMOS pixel using conventional CMOS processing techniques.

Abstract: An improved monolithic solid state imager comprises plural sub-arrays of respectively different kinds of pixels, an optional filter mosaic comprising color filters and clear elements, and circuitry to process the output of the pixels. The different kinds of pixels respond to respectively different spectral ranges. Advantageously the different kinds of pixels can be chosen from: 1) SWIR pixels responsive to short wavelength infrared (SWIR) in the range of approximately 800-1800 nm; 2) regular pixels responsive to visible and NIR radiation (400-1000 nm) and wideband pixels responsive to visible, NIR and SWIR radiation.

Abstract: A photodetector is formed from a body of semiconductor material substantially surrounded by dielectric surfaces. A passivation process is applied to at least one surface to reduce the rate of carrier generation and recombination on that surface. Photocurrent is read out from at least one electrical contact, which is formed on a doped region whose surface lies entirely on a passivated surface. Unwanted leakage current from un-passivated surfaces is reduced through one of the following methods: (a) The un-passivated surface is separated from the photo-collecting contact by at least two junctions; (b) The un-passivated surface is doped to a very high level, at least equal to the conduction band or valence band density of states of the semiconductor; (c) An accumulation or inversion layer is formed on the un-passivated surface by the application of an electric field.

Abstract: Imagers, pixels, and methods of using the same are disclosed for imaging in various spectra, such as visible, near infrared (IR), and short wavelength IR (SWIR). The imager may have an imaging array having pixels of different types. The different types of pixels may detect different ranges of wavelengths in the IR, or the SWIR, spectra. The pixels may include a filter which blocks some wavelengths of radiation in the IR spectrum while passing other wavelengths. The filter may be formed of a semiconductor material, and therefore may be easily integrated with a CMOS pixel using conventional CMOS processing techniques.

Abstract: A photodetector is formed from a body of semiconductor material substantially surrounded by dielectric surfaces. A passivation process is applied to at least one surface to reduce the rate of carrier generation and recombination on that surface. Photocurrent is read out from at least one electrical contact, which is formed on a doped region whose surface lies entirely on a passivated surface. Unwanted leakage current from un-passivated surfaces is reduced through one of the following methods. (a) The un-passivated surface is separated from the photo-collecting contact by at least two junctions (b) The un-passivated surface is doped to a very high level, at least equal to the conduction band or valence band density of states of the semiconductor (c) An accumulation or inversion layer is formed on the un-passivated surface by the application of an electric field. Electrical contacts are made to all doped regions, and bias is applied so that a reverse bias is maintained across all junctions.

Abstract: In accordance with the invention, an improved image sensor comprises an array of germanium photosensitive elements integrated with a silicon substrate and integrated with silicon readout circuits. The silicon transistors are formed first on a silicon substrate, using well known silicon wafer fabrication techniques. The germanium elements are subsequently formed overlying the silicon by epitaxial growth. The germanium elements are advantageously grown within surface openings of a dielectric cladding. Wafer fabrication techniques are applied to the elements to form isolated germanium photodiodes. Since temperatures needed for germanium processing are lower than those for silicon processing, the formation of the germanium devices need not affect the previously formed silicon devices. Insulating and metallic layers are then deposited and patterned to interconnect the silicon devices and to connect the germanium devices to the silicon circuits.

Abstract: Imaging arrays comprising at least two different imaging pixel types are described. The different imaging pixel types may differ in their light sensitivities and/or light saturation levels. Methods of processing the output signals of the imaging arrays are also described, and may produce images having a greater dynamic range than would result from an imaging array comprising only one of the at least two different imaging pixel types.

Abstract: Optical imaging structures and methods are disclosed. One structure may be implemented as an imaging pixel having multiple photodetectors. The photodetectors may detect different wavelengths of incident radiation, and may be operated simultaneously or at separate times. An imager may include an imaging array of pixels of the type described. Methods of operating such structures are also described.

Abstract: Imagers, pixels, and methods of using the same are disclosed for imaging in various spectra, such as visible, near infrared (IR), and short wavelength IR (SWIR). The imager may have an imaging array having pixels of different types. The different types of pixels may detect different ranges of wavelengths in the IR, or the SWIR, spectra. The pixels may include a filter which blocks some wavelengths of radiation in the IR spectrum while passing other wavelengths. The filter may be formed of a semiconductor material, and therefore may be easily integrated with a CMOS pixel using conventional CMOS processing techniques.