Patents Assigned to e-Phocus, Inc.
  • Patent number: 7525168
    Abstract: A MOS or CMOS based active pixel sensor designed for operation with zero or close to zero potential across the pixel photodiodes to minimize or eliminate dark current. In preferred embodiments the pixel photodiodes are produced with a continuous pin or nip photodiode layer laid down over pixel electrodes of the sensor. In this preferred embodiment, the voltage potential across the pixel photodiode structures is maintained constant and close to zero, preferably less than 1.0 volts. This preferred embodiment enables the photodiode to be operated at a constant bias condition during the charge detection cycle. Setting this constant bias condition close to zero (near “short circuit” condition) assures that dark current is substantially zero.
    Type: Grant
    Filed: February 22, 2008
    Date of Patent: April 28, 2009
    Assignee: e-Phocus, Inc.
    Inventor: Tzu-Chiang Hsieh
  • Patent number: 7436038
    Abstract: A MOS or CMOS sensor for high performance imaging in broad spectral ranges including portions of the infrared spectral band. These broad spectral ranges may also include portions or all of the visible spectrum, therefore the sensor has both daylight and night vision capabilities. The sensor includes a continuous multi-layer photodiode structure on a many pixel MOS or CMOS readout array where the photodiode structure is chosen to include responses in the near infrared spectral ranges. A preferred embodiment incorporates a microcrystalline copper indium diselenide/cadmium sulfide photodiode structure on a CMOS readout array. An alternate preferred embodiment incorporates a microcrystalline silicon germanium photodiode structure on a CMOS readout array. Each of these embodiments provides night vision with image performance that greatly surpasses the GEN III night vision technology in terms of enhanced sensitivity, pixel size and pixel count.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: October 14, 2008
    Assignee: e-Phocus, Inc
    Inventors: Michael G. Engelmann, Calvin Chao, Tzu-Chiang Hsieh, Peter Martin, Milam Pender
  • Patent number: 7411233
    Abstract: An active pixel sensor for producing images from electron-hole producing radiation includes a crystalline semiconductor substrate having an array of electrically conductive diffusion regions, an interlayer dielectric (ILD) layer formed over the crystalline semiconductor substrate and comprising an array of contact electrodes, and an interconnect structure formed over the ILD layer, wherein the interconnect structure includes at least one layer comprising an array of conductive vias. An array of patterned metal pads is formed over the interconnect structure and are electrically connected to an array of charge collecting pixel electrodes. A radiation absorbing structure includes a photoconductive N-I-B-P photodiode layer formed over the interconnect structure, and a surface electrode layer establishes an electrical field across the radiation absorbing structure and between the surface electrode layer and each of the array of charge collecting pixel electrodes.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: August 12, 2008
    Assignee: e-Phocus, Inc
    Inventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender
  • Patent number: 7276749
    Abstract: A microcrystalline germanium image sensor array. The array includes a number of pixel circuits fabricated in or on a substrate. Each pixel circuit comprises a charge collecting electrode for collecting electrical charges and a readout means for reading out the charges collected by the charge collecting electrode. A photodiode layer of charge generating material located above the pixel circuits convert electromagnetic radiation into electrical charges. This photodiode layer includes microcrystalline germanium and defines at least an n-layer, and i-layer and a p-layer. The sensor array also includes and a surface electrode in the form of a grid or thin transparent layer located above the layer of charge generating material. The sensor is especially useful for imaging in visible and near infrared spectral regions of the electromagnetic spectrum and provides imaging with starlight illumination.
    Type: Grant
    Filed: February 24, 2006
    Date of Patent: October 2, 2007
    Assignee: e-Phocus, Inc.
    Inventors: Peter Martin, Michael G. Engelman, Calvin Chao, Teu Chiang Hsieh, Milan Pender
  • Patent number: 7196391
    Abstract: A MOS or CMOS sensor with a multi-layer photodiode layer covering an array of active pixel circuits. The multi-layer photodiode layer of each pixel is fabricated as continuous layers of charge generating material on top of the MOS and/or CMOS pixel circuits so that extremely small pixels are possible with almost 100 percent packing factors. The sensor includes special features to minimize or eliminate pixel to pixel crosstalk. A micro-lens array with a micro-lens positioned above each pixel directs light illuminating the pixel toward the central portion of the pixel and away from its edges. Also, preferably carbon is added to doped amorphous silicon N or P bottom layer of the multi-layer photodiode layer to increase the electrical resistivity in the bottom layer to further discourage crosstalk. In preferred embodiments each of the pixels define a tiny surface area equal to or larger than about 3.24 square microns and smaller than or equal to about 25 square microns.
    Type: Grant
    Filed: July 5, 2006
    Date of Patent: March 27, 2007
    Assignee: e-Phocus, Inc.
    Inventor: Tzu-Chiang Hsieh
  • Patent number: 6809358
    Abstract: A MOS or CMOS based photoconductor on active pixel image sensor. Thin layers of semi-conductor material, doped to PIN or NIP photoconducting layers, located above MOS and/or CMOS pixel circuits produce an array of layered photodiodes. Positive and negative charges produced in the layered photodiodes are collected and stored as electrical charges in the MOS and/or CMOS pixel circuits. The present invention also provides additional MOS or CMOS circuits for reading out the charges and for converting the charges into images. With the layered photodiode of each pixel fabricated as continuous layers of charge generating material on top of the MOS and/or CMOS pixel circuits, extremely small pixels are possible with almost 100 percent packing factors. MOS and CMOS fabrication techniques permit sensor fabrication at very low costs. In preferred embodiments all of the sensor circuits are incorporated on or in a single crystalline substrate along with the sensor pixel circuits.
    Type: Grant
    Filed: August 26, 2003
    Date of Patent: October 26, 2004
    Assignee: e-Phocus, Inc.
    Inventors: Tzu-Chiang Hsieh, Calvin Chao
  • Patent number: 6798033
    Abstract: An active pixel sensor for producing images from electron-hole producing radiation includes a crystalline semiconductor substrate having an array of electrically conductive diffusion regions, an interlayer dielectric (ILD) layer formed over the crystalline semiconductor substrate and comprising an array of contact electrodes, and an interconnect structure formed over the ILD layer, wherein the interconnect structure includes at least one layer comprising an array of conductive vias. An array of patterned metal pads is formed over the interconnect structure and are electrically connected to an array of charge collecting pixel electrodes. A radiation absorbing structure includes a photoconductive N-I-B-P photodiode layer formed over the interconnect structure, and a surface electrode layer establishes an electrical field across the radiation absorbing structure and between the surface electrode layer and each of the array of charge collecting pixel electrodes.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: September 28, 2004
    Assignee: e-Phocus, Inc.
    Inventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender
  • Patent number: 6791130
    Abstract: An active pixel sensor for producing images from electron-hole producing radiation includes a crystalline semiconductor substrate having an array of electrically conductive diffusion regions, an interlayer dielectric (ILD) layer formed over the crystalline semiconductor substrate and comprising an array of contact electrodes, and an interconnect structure formed over the ILD layer, wherein the interconnect structure includes at least one layer comprising an array of conductive vias. An array of patterned metal pads is formed over the interconnect structure and are electrically connected to an array of charge collecting pixel electrodes. A radiation absorbing structure includes a photoconductive N-I-B-P photodiode layer formed over the interconnect structure, and a surface electrode layer establishes an electrical field across the radiation absorbing structure and between the surface electrode layer and each of the array of charge collecting pixel electrodes.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: September 14, 2004
    Assignee: E-Phocus, Inc.
    Inventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender
  • Patent number: 6730914
    Abstract: An active pixel sensor. A solid state radiation detection unit may be fabricated using a semiconductor substrate having a plurality of CMOS pixel circuits incorporated into the substrate. An array of pixel circuits includes within each circuit a charge collecting pixel electrode, a charge sensing node, a gate bias transistor for separating the charge collecting pixel electrode and the charge sensing node and for maintaining the pixel electrodes at substantially equal potential, and a pixel capacitor to store charges collected by the charge collecting pixel electrodes. A charge measuring circuit comprising at least one transistor may also be configured with each pixel circuit. The sensor may further include a radiation absorbing layer comprised of photoconductive material, as well as a surface electrode layer comprised of electrically conducting material.
    Type: Grant
    Filed: February 5, 2002
    Date of Patent: May 4, 2004
    Assignee: e-Phocus, Inc.
    Inventors: Calvin Chao, Tzu-Chiang Hsieh
  • Patent number: 6730900
    Abstract: A novel MOS or CMOS based active sensor array for producing electronic images from electron-hole producing light. Each pixel of the array includes a layered photodiode for converting the electron-hole producing light into electrical charges and MOS and/or CMOS pixel circuits located under the layered photodiodes for collecting the charges. The present invention also provides additional MOS or CMOS circuits in and/or on the same crystalline substrate for converting the collected charges into images and manipulating image data. The layered photodiode of each pixel is fabricated as continuous layers of charge generating material on top of the MOS and/or CMOS pixel circuits so that extremely small pixels are possible with almost 100 percent packing factors. In a preferred embodiment the sensor is a 0.3 mega pixel (3.2 mm×2.4 mm, 640×480) array of 5 micron square pixels which is compatible with a lens of {fraction (1/4.5)} inch optical format.
    Type: Grant
    Filed: February 22, 2003
    Date of Patent: May 4, 2004
    Assignee: e-Phocus, Inc.
    Inventors: Tzu-Chiang Hsish, Calvin Chao