Shallow trench isolation (STI) structure for suppressing dark current and method of forming
Granted: March 22, 2022
Patent Number:
11282890
A method of fabricating a target shallow trench isolation (STI) structure between devices in a wafer-level image sensor having a large number of pixels includes etching a trench, the trench having a greater depth and width than a target STI structure and epitaxially growing the substrate material in the trench for a length of time necessary to provide the target depth and width of the isolation structure. An STI structure formed in a semiconductor substrate includes a trench etched in…
Pixel, associated image sensor, and method
Granted: March 22, 2022
Patent Number:
11282886
A pixel includes a semiconductor substrate, an upper surface thereof forming a trench having a trench depth relative to a planar region of the upper surface surrounding the trench, and in a plane perpendicular to the planar region; an upper width between the planar region and an upper depth that is less than the trench depth; and a lower width, between the upper depth and the trench depth, that is less than the upper width. A floating diffusion region adjacent to the trench extends away…
Structure light module using vertical cavity surface emitting laser array and folding optical element
Granted: March 22, 2022
Patent Number:
11280988
A structure light module comprises: a VCSEL substrate comprising a VCSEL array comprising a plurality of individual VCSELs; a first spacer disposed on the VCSEL substrate; a first wafer level lens comprising a glass substrate and at least a replicated lens on a first surface of the glass substrate disposed on the first spacer; a FOE disposed on the first wafer level lens; a second spacer disposes on the FOE; a second wafer level lens comprising a glass substrate and at least a replicated…
Wide dynamic range image sensor with global shutter
Granted: March 8, 2022
Patent Number:
11272126
An image sensor includes a photodiode disposed in a semiconductor material to generate image charge in response to incident light, and a first transfer gate is coupled to the photodiode to extract image charge from the photodiode in response to a first transfer signal. A first storage gate is coupled to the first transfer gate to receive the image charge from the first transfer gate, and a first output gate is coupled to the first storage gate to receive the image charge from the first…
Image sensor with fully depleted silicon on insulator substrate
Granted: March 1, 2022
Patent Number:
11264419
A fully depleted silicon on insulator (FDSOI) is employed to reduce diffusion leakage (e.g., gate induced drain leakage, junction leakage, etc.) associated with the diffusion regions of a pixel cell. The buried oxide (BOX) layer, for example, fully isolates the transistor channel region, such as an (N) channel region of the pixel cell from the photodiode(s) of the pixel region, eliminating the junction leakage path, thus leading to a reduction in diffusion leakage and an increase device…
Image sensor with shared microlens
Granted: February 15, 2022
Patent Number:
11252381
An image sensor includes a plurality of photodiodes, a plurality of color filters, and a plurality of microlenses. The plurality of photodiodes are arranged as a photodiode array, each of the plurality of photodiodes disposed within respective portions of a semiconductor material with a first lateral area. The plurality of color filters are arranged as a color filter array optically aligned with the photodiode array. Each of the plurality of color filters having a second lateral area…
Switching techniques for fast voltage settling in image sensors
Granted: February 15, 2022
Patent Number:
11252346
Switching techniques for fast voltage settling in image sensors are described. In one embodiment, a transfer gate (TX) driver circuit of an image sensor includes a TX driver configured to provide a TX driver voltage to a plurality of pixels of an image sensor. A power supply (NVDD) is operationally coupled to the TX driver. A first switch (SW1) operationally coupling an outside capacitance (Cext) and the TX driver. A second switch (SW2) operationally coupling the Cext and the NVDD. A…
Fully buried color filter array of image sensor
Granted: February 8, 2022
Patent Number:
11245823
An image sensor includes a substrate. An array of photodiodes is disposed in the substrate. A plurality of spacers is arranged in a spacer pattern. At least one spacer of the plurality of spacers has an aspect ratio of 18:1 or greater. A buffer layer is disposed between the substrate and the spacer pattern. An array of color filters is disposed in the spacer pattern.
Deep trench isolation (DTI) structure for CMOS image sensor
Granted: February 8, 2022
Patent Number:
11244979
A semiconductor structure for a CMOS image sensor includes a semiconductor substrate having a first side and a second side. A photodiode is disposed in the semiconductor substrate proximate to the first side. The photodiode accumulates image charge photogenerated in the photodiode in response to incident light directed through the second side. A deep trench isolation structure enclosing the photodiode. The deep trench isolation structure extends from the second side toward the first…
Image sensor with capacitor randomization for column gain
Granted: February 1, 2022
Patent Number:
11240458
A pixel cell readout circuit includes a bitline input stage coupled to a bitline to receive an image signal from a pixel cell. A capacitor ratio circuit is coupled to the bitline input stage. A gain of the bitline input stage is responsive to a capacitor ratio provided by the capacitor ratio circuit to the bitline input stage. A switch control circuit is coupled to receive a gain signal. The switch control circuit is coupled to generate a randomized pattern selection signal coupled to be…
Column amplifier reset circuit
Granted: February 1, 2022
Patent Number:
11240456
An amplifier circuit for use in an image sensor includes a common source amplifier coupled to receive an input signal representative of an image charge from a pixel cell of the image sensor. An auto-zero switch is coupled between an input of the common source amplifier and an output of the common source amplifier. A feedback capacitor is coupled to the input of the common source amplifier. An offset switch is coupled to the feedback capacitor and is further coupled to a reset voltage and…
Hybrid CMOS image sensor with event driven sensing
Granted: February 1, 2022
Patent Number:
11240454
An image sensor includes a source follower coupled to a photodiode to generate an image signal responsive to photogenerated charge. The image signal is received by image readout circuitry through a row select transistor. A reset transistor resets the photogenerated charge. A first node of mode select circuit is coupled to the reset transistor, a second node is coupled to a pixel supply voltage, and a third node is coupled to an event driven circuit. The mode select circuit couples the…
Digital CDS readout with 1.5 ADC conversions per pixel
Granted: January 25, 2022
Patent Number:
11233968
A CMOS image sensor comprises an array of pixels. A column of the pixel array is coupled to a readout column. The readout column is couple to a readout circuitry (RC) that reads out image data from the pixel array. The RC comprises a sampling switch which is coupled to a 1-column successive approximation register (SAR) analog-to-digital converter (ADC). The 1-column SAR ADC comprises a differential comparator, a local SAR control, and a digital-to-analog converter (DAC). The sampling…
Devices and methods for obtaining three-dimensional shape information using polarization and phase detection photodiodes
Granted: January 25, 2022
Patent Number:
11233963
In some embodiments, an image sensor is provided. The image sensor comprises a plurality of photodiodes arranged as a photodiode array. The plurality of photodiodes includes a first set of photodiodes configured as phase detection photodiodes, and a second set of photodiodes configured as polarization detection photodiodes. In some embodiments, a controller is provided. The controller comprises circuitry configured to process signals from a first set of photodiodes of a photodiode array…
Metal routing in image sensor using hybrid bonding
Granted: January 25, 2022
Patent Number:
11233088
A method of routing electrical connections in a wafer-on-wafer structure comprises, bonding a metal bonding pad of a first wafer to a metal bonding pad of a second wafer; bonding first wafer to the second wafer with a material different from the metal bonding pads; forming metal interconnect structures connecting the metal bonding pad of the first wafer to a first device disposed within a first and second side of the first wafer; and forming metal interconnect structures connecting the…
Image sensor with partially encapsulating attenuation layer
Granted: January 25, 2022
Patent Number:
11233080
A pixel cell includes a first photodiode, a second photodiode, a first deep trench isolation region, a second deep trench isolation region, a buffer oxide layer, and a light attenuation layer. The attenuation layer partially encapsulates the first photodiode by extending laterally from the first deep trench isolation region to the second deep trench isolation region between the semiconductor material and the buffer oxide layer.
Techniques for robust anti-spoofing in biometrics using polarization cues for NIR and visible wavelength band
Granted: January 25, 2022
Patent Number:
11232284
A system comprising a polarization CMOS image sensor, at least one processor and a non-transitory computer-readable medium having computer-executable instructions stored thereon that, in response to execution by the at least one processor, cause the system to perform actions including receiving, from the polarization CMOS image sensor, polarization information and two-dimensional image information. The polarization information is processed using a machine learning model to generate an…
Dual mode stacked photomultipliers suitable for use in long range time of flight applications
Granted: January 11, 2022
Patent Number:
11221400
A photomultiplier pixel cell includes a photon detector coupled to detect an incident photon. A quenching circuit is coupled to quench an avalanche current in the photon detector. An enable circuit is coupled to the photon detector to enable and disable the photon detector in response to an enable signal. A buffer circuit is coupled to the photon detector to generate a digital output signal having a pulse width interval in response to the avalanche current triggered in the photon…
Image sensor with split pixel structure and method of manufacturing thereof
Granted: January 4, 2022
Patent Number:
11217613
An image sensor includes a substrate material. The substrate material includes a plurality of photodiodes disposed therein. The plurality of photodiodes includes a plurality of small photodiodes (SPDs) and a plurality of large photodiodes (LPDs) larger than the SPDs. An array of color filters is disposed over the substrate material. A buffer layer is disposed between the substrate material and the array of color filters. A metal pattern is disposed between the color filters in the array…
Image sensor with voltage supply grid clamping
Granted: January 4, 2022
Patent Number:
11218659
An image sensing device includes an image sensing circuit, a voltage supply grid, bitlines, and a control circuit. The image sensing circuit includes pixels arranged in rows and columns. Each one of the bitlines is coupled to a corresponding one of the columns. The voltage supply grid is coupled to the pixels. The control circuit is coupled to output at least a row select signal and a transfer signal to the rows. Each one of the rows is selectively coupled to the bitlines to selectively…
