Abstract: A method for the fabrication of avalanche photodiodes (APDs) useful as high-sensitivity Geiger-mode APDs. The photodetector is formed on a semiconductor substrate of indium phosphide (InP) having epitaxial layers, including indium gallium arsenide (InGaAs) as the photodetecting layer, with n-doped InP to one side, and layers of InP incorporating p-doped regions on the opposite side. The p-doped regions serve to define an array of micro-cells, which may have a hexagonal configuration. A well may be etched through the epitaxial structures, allowing one electrode to contact the n-doped InP layer and another electrode to contact the p-doped InP regions, with both electrodes on the same side of the detector. Bonding techniques then attach the semiconductor wafer to a support substrate, which may additionally be configured with electronic circuitry positioned to electrically contact the electrodes on the semiconductor wafer surface, and diced to form individual devices.

Abstract: Disclosed herein are avalanche photodiodes (APDs) particularly useful for high-sensitivity Geiger-mode APDs formed using an array of micro-cells. The photodetector is formed on a semiconductor substrate of indium phosphide (InP) having epitaxial layers, including indium gallium arsenide (InGaAs) as the photodetecting layer, with n-doped InP to one side, and layers of InP incorporating p-doped regions on the opposite side. The p-doped regions may serve to define an array of micro-cells, which may be arranged in a hexagonal pattern. A well may be etched through the epitaxial structures, allowing an electrode that contacts the n-doped InP layer and another that contacts the p-doped InP regions to be patterned on the same side of the detector. Flip-chip bonding techniques can then attach the semiconductor wafer to a stronger support substrate, which may additionally be configured with electronic circuitry positioned to electrically contact the electrodes on the semiconductor wafer surface.

Abstract: Disclosed herein are avalanche photodiodes (APDs) particularly useful for high-sensitivity Geiger-mode APDs formed using an array of micro-cells. The photodetector is formed on a semiconductor substrate of indium phosphide (InP) having epitaxial layers, including indium gallium arsenide (InGaAs) as the photodetecting layer, with n-doped InP to one side, and layers of InP incorporating p-doped regions on the opposite side. The p-doped regions may serve to define an array of micro-cells, which may be arranged in a hexagonal pattern. A well may be etched through the epitaxial structures, allowing an electrode that contacts the n-doped InP layer and another that contacts the p-doped InP regions to be patterned on the same side of the detector. Flip-chip bonding techniques can then attach the semiconductor wafer to a stronger support substrate, which may additionally be configured with electronic circuitry positioned to electrically contact the electrodes on the semiconductor wafer surface.

Abstract: This Application discloses methods for fabricating and packaging avalanche photodiodes (APDs), particularly useful for high sensitivity Geiger-mode APDs formed using an array of micro-cells. The photodetector is formed on a semiconductor wafer of indium phosphide (InP) having epitaxial layers, including indium gallium arsenide (InGaAs) as the photodetecting layer, with n-doped InP to one side, and layers of InP incorporating p-doped regions on the opposite side. The p-doped regions may be used to define the array of micro-cells. The photodetector is packaged by etching a well into the epitaxial structure on the semiconductor wafer, allowing an electrode to be patterned that contacts the n-doped InP layer and another that contacts the p-doped InP regions. Flip-chip bonding techniques can then attach the semiconductor wafer to a stronger support substrate, which may additionally be configured with electronic circuitry positioned to electrically contact the electrodes on the semiconductor wafer surface.