公开(公告)号：US11355537B2

公开(公告)日：2022-06-07

申请号：US16655017

申请日：2019-10-16

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Hui Zang ,  Gang Chen

IPC: H01L27/146

Abstract: A pixel cell includes a photodiode buried beneath a first side of semiconductor material and coupled to photogenerate image charge in response to incident light. A transfer gate is disposed over the photodiode and includes a vertical transfer gate portion extending a first distance from the first side into the semiconductor material. A floating diffusion region is disposed in the semiconductor material proximate to the transfer gate and is coupled to transfer the image charge from the photodiode toward the first side of the semiconductor material and into the floating diffusion region in response to a transfer control signal. A first pixel transistor having a first gate is disposed over the photodiode proximate to the first side of the semiconductor material. The first gate has a ring structure laterally surrounding the floating diffusion region and the transfer gate at the first side of the semiconductor material.

公开(公告)号：US11348957B2

公开(公告)日：2022-05-31

申请号：US16729163

申请日：2019-12-27

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Seong Yeol Mun ,  Young Woo Jung

IPC: H01L27/146

Abstract: Image sensors include a photodiode formed in a substrate material and a transistor coupled to the photodiode. The transistor has a trench structure formed in the substrate material, an isolation layer disposed on the substrate material, and a gate disposed on the isolation layer and extending into the trench structure. The trench structure has a polygonal cross section in a channel width plane, the polygonal cross section defining at least four sidewall portions of the substrate material, which contribute to an effective channel width measured in the channel width plane that is wider than a planar channel width of the transistor.

公开(公告)号：US11302727B2

公开(公告)日：2022-04-12

申请号：US16689938

申请日：2019-11-20

Applicant: OmniVision Technologies, Inc.

Inventor： Hui Zang ,  Qin Wang ,  Gang Chen

IPC: H01L27/14 ,  H01L27/146 ,  H01L29/78 ,  H01L29/66 ,  H01L29/423

Abstract: A pixel includes a semiconductor substrate, a photodiode region, a floating diffusion region, and a dielectric layer. The substrate has a top surface forming a trench lined by the dielectric layer, and having a trench depth relative to a planar region of the top surface. The photodiode region is in the substrate and includes a bottom photodiode section beneath the trench and a top photodiode section adjacent to the trench, adjoining the bottom photodiode section, and extending toward the planar region to a photodiode depth less than the trench depth. The floating diffusion region is adjacent to the trench and has a junction depth less than the trench depth. A top region of the dielectric layer is between the planar region and the junction depth. A bottom region of the dielectric layer is between the photodiode depth and the trench depth, and thicker than the top region.

公开(公告)号：US11290674B1

公开(公告)日：2022-03-29

申请号：US17127571

申请日：2020-12-18

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Hiroaki Ebihara

IPC: H04N5/378 ,  H01L27/146 ,  H04N5/374 ,  H04N5/3745

Abstract: A pixel cell readout circuit includes an amplifier and a capacitor switch circuit that includes a first routing path coupled to an input of the amplifier. A second routing path includes switches coupled in series along the second routing path. A first end of the second routing path is coupled to a bitline. A second end of the second routing path is coupled to an output of the amplifier. Only one of the switches is turned off and a remainder of the switches are turned on. Capacitors are coupled in parallel between the first routing path and the second routing path. A first end of each of the capacitors is coupled to the first routing path. A second end of each of the capacitors is coupled to the second routing path. The switches are interleaved among the second ends of the capacitors along the second routing path.

公开(公告)号：US11282890B2

公开(公告)日：2022-03-22

申请号：US16748604

申请日：2020-01-21

Applicant: OmniVision Technologies, Inc.

Inventor： Seong Yeol Mun

IPC: H01L27/146

Abstract: 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 the substrate having a depth and width greater than that of the STI structure, and semiconductor material epitaxially grown in the trench to provide a critical dimension and target depth of the STI structure. An image sensor includes a semiconductor substrate, a photodiode region, a pixel transistor region and an STI structure between the photodiode region and the pixel transistor region.

公开(公告)号：US11272126B2

公开(公告)日：2022-03-08

申请号：US17204786

申请日：2021-03-17

Applicant: OmniVision Technologies, Inc.

Inventor： Sohei Manabe ,  Keiji Mabuchi

IPC: H04N5/353 ,  H04N5/355 ,  H04N5/3745 ,  H04N5/378

Abstract: 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 storage gate. A first capacitor is coupled to the first output gate to store the image charge.

公开(公告)号：US11264419B2

公开(公告)日：2022-03-01

申请号：US16730756

申请日：2019-12-30

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Seong Yeol Mun

IPC: H01L27/146

Abstract: 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 operation speed. An increase of full well capacity can also be realized by the absence of isolation structure, such as trench isolation or isolation implant structure.

公开(公告)号：US20220059599A1

公开(公告)日：2022-02-24

申请号：US16998783

申请日：2020-08-20

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Qin Wang ,  Gang Chen

IPC: H01L27/146

Abstract: A device includes a photodiode, a floating diffusion region, a transfer gate, and a channel region. The photodiode is disposed in a semiconductor material. The photodiode is coupled to generate charge in response to incident light. The floating diffusion region is disposed in the semiconductor material. The transfer gate is disposed between the photodiode and the floating diffusion region. The channel region associated with the transfer gate is in the semiconductor material proximate to the transfer gate. The transfer gate is coupled to transfer the charge from the photodiode to the floating diffusion region through the channel region in response to a transfer signal coupled to be received by the transfer gate. The transfer gate includes a plurality of fin structures that extend into the semiconductor material and the photodiode.

公开(公告)号：US11240456B2

公开(公告)日：2022-02-01

申请号：US16441674

申请日：2019-06-14

Applicant: OmniVision Technologies, Inc.

Inventor： Hiroaki Ebihara ,  Zheng Yang

IPC: H04N5/378 ,  H04N5/365 ,  H04N5/3745 ,  H01L27/146

Abstract: 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 an output of the amplifier circuit. The auto-zero switch and the offset switch are configured to couple the feedback capacitor to the reset voltage during a reset of the amplifier circuit. The offset switch is configured to couple the feedback capacitor to the output of the amplifier circuit after the reset of the amplifier circuit.

公开(公告)号：US20220005846A1

公开(公告)日：2022-01-06

申请号：US16946743

申请日：2020-07-02

Applicant: OmniVision Technologies, Inc.

Inventor： Seong Yeol Mun ,  Heesoo Kang

IPC: H01L27/146

Abstract: A pixel cell with an elevated floating diffusion region is formed to reduce diffusion leakage (e.g., gate induced drain leakage, junction leakage, etc.). The floating diffusion region can be elevated by separating a doped floating diffusion region from the semiconductor substrate by disposing an intervening layer (e.g., undoped, lightly doped, etc.) on the semiconductor substrate and beneath the doped floating diffusion region. For instance, the elevated floating diffusion region can be formed by stacked material layers composed of a lightly or undoped base or intervening layer and a heavy doped (e.g., As doped) “elevated” layer. In some examples, the stacked material layers can be formed by first and second epitaxial growth layers.