Patents Assigned to e-Phocus
  • Patent number: 7906826
    Abstract: A CMOS image sensor with a many million pixel count. Applicants have developed techniques for combining its continuous layer photodiode CMOS sensor technology with CMOS integrated circuit lithography stitching techniques to provide digital cameras with an almost unlimited number of pixels. A preferred CMOS stitching technique exploits the precise alignment accuracy of CMOS stepper processes by using specialized mask sets to repeatedly produce a single pixel array pattern many times on a single silicon wafer with no pixel array discontinuities. The single array patterns are stitched together lithographically to form a pixel array of many million pixels. A continuous multilayer photodiode layer is deposited over the top of the many million pixel array to provide a many million pixel sensor with a fill factor of 100 percent or substantially 100 percent.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: March 15, 2011
    Assignee: e-Phocus
    Inventors: Peter Martin, Paul Johnson, Chris Sexton
  • Patent number: 7820525
    Abstract: A method for wafer-to-wafer bonding of a sensor readout circuitry separately fabricated with a silicon substrate to a photodiode device made of non-silicon materials grown from a separate substrate. In preferred embodiments the non-silicon materials are epitaxially grown on a silicon wafer. The bonding technique of preferred embodiments of the present invention utilizes lithographically pre-fabricated metallic interconnects to connect each of a number of pixel circuits on a readout circuit wafer to each of a corresponding number of pixel photodiodes on a photodiode wafer. The metallic interconnects are extremely small (with widths of about 2 to 4 microns) compared to prior art bump bonds with the solder balls of diameter typically larger than 20 microns. The present invention also provides alignment techniques to assure proper alignment of the interconnects during the bonding step.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: October 26, 2010
    Assignee: e-Phocus
    Inventor: Tzu-Chiang Hsieh
  • Patent number: 7786543
    Abstract: A MOS or CMOS based active pixel sensor with special sampling features to substantially eliminate clock noise. The sensor includes an array of pixels fabricated in or on a substrate, each pixel defining a charge collection node on which charges generated inside a photodiode region are collected, a charge integration node, at which charges generated in said pixel are integrated to produce pixel signals, a charge sensing node from which reset signals and the pixel signals are sensed. In preferred embodiments the sensor includes a continuous electromagnetic radiation detection structure located above the pixel circuits providing a photodiode region for each pixel. The sensor includes integrated circuit elements adapted to maintain voltage potentials of the charge integration nodes substantially constant during charge integration cycles. The sensor also includes integrated circuit elements having electrical capacitance adapted to store charges providing an electrical potential at the charge integration node.
    Type: Grant
    Filed: August 17, 2007
    Date of Patent: August 31, 2010
    Assignee: e-Phocus
    Inventor: Tzu-Chiang Hsieh
  • 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