Patents by Inventor Calvin Chao
Calvin Chao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 7436038Abstract: 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: GrantFiled: February 23, 2004Date of Patent: October 14, 2008Assignee: e-Phocus, IncInventors: Michael G. Engelmann, Calvin Chao, Tzu-Chiang Hsieh, Peter Martin, Milam Pender
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Photoconductor-on-active-pixel (POAP) sensor utilizing a multi-layered radiation absorbing structure
Patent number: 7411233Abstract: 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: GrantFiled: August 27, 2002Date of Patent: August 12, 2008Assignee: e-Phocus, IncInventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender -
Patent number: 7276749Abstract: 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: GrantFiled: February 24, 2006Date of Patent: October 2, 2007Assignee: e-Phocus, Inc.Inventors: Peter Martin, Michael G. Engelman, Calvin Chao, Teu Chiang Hsieh, Milan Pender
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Publication number: 20060267054Abstract: 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: ApplicationFiled: February 24, 2006Publication date: November 30, 2006Inventors: Peter Martin, Michael Engelman, Calvin Chao, Teu Hsieh, Milan Pender
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Publication number: 20060164533Abstract: An electronic imaging sensor. The sensor includes an array of photo-sensing pixel elements for producing image frames. Each pixel element defines a photo-sensing region and includes a charge collecting element for collecting electrical charges produced in the photo-sensing region, and a charge storage element for the storage of the collected charges. The sensor also includes charge sensing elements for sensing the collected charges, and charge-to-signal conversion elements. The sensor also includes timing elements for controlling the pixel circuits to produce image frames at a predetermined normal frame rate based on a master clock signal (such as 12 MHz or 10 MHz). This predetermined normal frame rate which may be a video rate (such as about 30 frames per second or 25 frames per second) establishes a normal maximum per frame exposure time.Type: ApplicationFiled: March 24, 2006Publication date: July 27, 2006Inventors: Tzu-Chiang Hsieh, Calvin Chao
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Publication number: 20050104089Abstract: 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: ApplicationFiled: February 23, 2004Publication date: May 19, 2005Inventors: Michael Engelmann, Calvin Chao, Tzu-Chiang Hsieh, Peter Martin, Milam Pender
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Publication number: 20050012840Abstract: The present invention provides a MOS or CMOS based active sensor array for producing electronic images from charge producing light. Each pixel of the array includes a layered photodiode for converting the 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 processing the collected charges for the purposes of producing images. 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 preferred embodiments, pixel crosstalk is minimized by careful design of the bottom photodiode layer with the addition of carbon to the doped amorphous silicon N or P layer to increase the electrical resistivity.Type: ApplicationFiled: August 18, 2004Publication date: January 20, 2005Inventors: Tzu-Chiang Hsieh, Calvin Chao
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Patent number: 6809358Abstract: 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: GrantFiled: August 26, 2003Date of Patent: October 26, 2004Assignee: e-Phocus, Inc.Inventors: Tzu-Chiang Hsieh, Calvin Chao
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Photoconductor-on-active-pixel (POAP) sensor utilizing a multi-layered radiation absorbing structure
Patent number: 6798033Abstract: 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: GrantFiled: August 27, 2002Date of Patent: September 28, 2004Assignee: e-Phocus, Inc.Inventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender -
Photoconductor-on-active-pixel (POAP) sensor utilizing a multi-layered radiation absorbing structure
Patent number: 6791130Abstract: 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: GrantFiled: August 27, 2002Date of Patent: September 14, 2004Assignee: E-Phocus, Inc.Inventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender -
Publication number: 20040135209Abstract: The present invention provides 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 processing the collected charges for the purposes of producing images. 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 preferred embodiments, pixel crosstalk is minimized by careful design of the bottom photodiode layer with the addition of carbon to the doped amorphous silicon N or P layer to increase the electrical resistivity.Type: ApplicationFiled: December 23, 2003Publication date: July 15, 2004Inventors: Tzu-Chiang Hsieh, Calvin Chao
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Patent number: 6730900Abstract: 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: GrantFiled: February 22, 2003Date of Patent: May 4, 2004Assignee: e-Phocus, Inc.Inventors: Tzu-Chiang Hsish, Calvin Chao
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Patent number: 6730914Abstract: 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: GrantFiled: February 5, 2002Date of Patent: May 4, 2004Assignee: e-Phocus, Inc.Inventors: Calvin Chao, Tzu-Chiang Hsieh
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Photoconductor-on-active-pixel (POAP) sensor utilizing a multi-layered radiation absorbing structure
Publication number: 20040041932Abstract: 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: ApplicationFiled: August 27, 2002Publication date: March 4, 2004Inventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender -
Photoconductor-on-active-pixel (POAP) sensor utilizing a multi-layered radiation absorbing structure
Publication number: 20040041930Abstract: 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: ApplicationFiled: August 27, 2002Publication date: March 4, 2004Inventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender -
Photoconductor-on-active-pixel (POAP) sensor utilizing a multi-layered radiation absorbing structure
Publication number: 20040041224Abstract: 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: ApplicationFiled: August 27, 2002Publication date: March 4, 2004Inventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender -
Photoconductor-on-active-pixel (POAP) sensor utilizing a multi-layered radiation absorbing structure
Publication number: 20040041219Abstract: 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: ApplicationFiled: August 27, 2002Publication date: March 4, 2004Inventors: Calvin Chao, Tzu-Chiang Hsieh, Michael Engelmann, Milam Pender -
Publication number: 20040036010Abstract: 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: ApplicationFiled: August 26, 2003Publication date: February 26, 2004Inventors: Tzu-Chiang Hsieh, Calvin Chao
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Publication number: 20030213915Abstract: An active pixel sensor is disclosed. In one embodiment, a solid state radiation detection unit may be fabricated using a semiconductor substrate having a plurality of CMOS pixel circuits incorporated into the substrate. Typically, each of an array of pixel circuits includes a charge collecting pixel electrode, a charge sensing node, a gate bias transistor separating the charge collecting pixel electrode and the charge sensing node, and a pixel capacitor to store charges collected by the charge collecting pixel electrode. 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. The sensor is typically configured with an array measurement circuit for measuring charges collected by the array of charge collecting pixel electrodes and for pixel data output.Type: ApplicationFiled: February 5, 2002Publication date: November 20, 2003Inventors: Calvin Chao, Tzu-Chiang Hsieh
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Publication number: 20030146372Abstract: 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: ApplicationFiled: February 22, 2003Publication date: August 7, 2003Inventors: Tzu-Chiang Hsish, Calvin Chao