An image sensor is described comprising a first, a second, and a third stack mounted together. The first stack includes a first semiconductor substrate with a photoelectric conversion region, a floating diffusion region, and a transmission gate. The photoelectric conversion region absorbs light, and the charges freed by the light absorption are stored in the floating diffusion region prior to being transferred to other circuitry by the transmission gate. The transmission gate comprises an etch stop film on an upper surface and on a sidewall. The second stack, attached to the first stack, includes a second semiconductor substrate in which is located a pixel gate. The pixel gate is electrically connected with the floating diffusion region and further comprises a gate spacer on a sidewall of the pixel gate. The third stack, attached to the second stack, includes a logic transistor.

Image sensors may include a base substrate including a substrate layer, a buried insulation layer on the substrate layer, and a semiconductor layer on the buried insulation layer, a photo sensing device in the substrate layer, a buried impurity region spaced apart from the photo sensing device in an upper portion of the substrate layer, a transfer gate including a vertical gate extending through the semiconductor layer and the buried insulation layer and extending into an inner portion of the substrate layer, which is between the photo sensing device and the buried impurity region, a planar gate on the semiconductor layer, and a gate insulation layer between the substrate layer and the planar gate.

Various embodiments of the present disclosure are directed towards a method for forming a pixel sensor. The method comprises forming a photodetector in a substrate. The substrate is patterned to define an opening above the photodetector. A gate electrode is formed within the opening, where the gate electrode has a top conductive body overlying a bottom conductive body. A first segment of a sidewall of the top conductive body contacts the bottom conductive body. A floating diffusion node is formed in the substrate laterally adjacent to the gate electrode. A second segment of the sidewall of the top conductive body overlies the floating diffusion node.

To improve an image quality in a solid-state imaging element that performs differential amplification. A reference-side amplification transistor supplies a reference current corresponding to a predetermined reference potential. A read-side amplification transistor supplies a signal current corresponding to a difference between a potential of a gate and the reference potential from a drain to a source. A pair of reset transistors initializes the potential of the gate and the reference potential. A potential control circuit controls a potential difference between the gate and the drain to a predetermined value when the potential of the gate and the reference potential are initialized.

A method of manufacturing a transistor structure includes forming a plurality of trenches in a substrate, lining the plurality of trenches with a dielectric material, forming first and second substrate regions at opposite sides of the plurality of trenches, and filling the plurality of trenches with a conductive material. The plurality of trenches includes first and second trenches aligned between the first and second substrate regions, and filling the plurality of trenches with the conductive material includes the conductive material extending continuously between the first and second trenches.

A thin-film transistor to be used in an X-ray sensor includes a gate electrode, a semiconductor layer, and a gate insulating layer located between the semiconductor layer and the gate electrode. The gate insulating layer includes a first region having an interface with the gate electrode, a second region having an interface with the semiconductor layer, and a third region located between the first region and the second region. Each of the first region and the second region has a density of electron trap states and a density of hole trap states that are higher than whichever of a density of electron trap states and a density of hole trap states of the third region that is lower.

An imaging circuit includes a first vertical trench gate and a neighboring second vertical trench gate. The imaging circuit includes a gate control circuit. The gate control circuit operates in a first operating mode to generate a first space charge region accelerating photogenerated charge carriers of a first charge-carrier type to a first collection contact in and in a second operating mode to generate a second space charge region accelerating photogenerated charge carriers of the first charge-carrier type to the first collection contact. The imaging circuit further includes an image processing circuit which determines distance information of an object based on photogenerated charge carriers of the first charge carrier type collected at the first collection contact in the first operating mode and color information of the object based on photogenerated charge carriers of the first charge carrier type collected at the first collection contact in the second operating mode.

There is provided an imaging device manufacturing method contributing to improved reliability and yield. The method includes forming a first insulating film on a polysilicon film and then removing a portion of the first insulating film formed on a second main surface and a portion of the first insulating film formed on a side surface of the substrate to expose a polysilicon film. After the polysilicon film is exposed, a second insulating film is formed on the first main surface by a plasma chemical vapor deposition (CVD) method.

A backside illuminated image sensor includes a semiconductor material with a plurality of photodiodes disposed in the semiconductor material, and a transfer gate electrically coupled to a photodiode in the plurality of photodiodes to extract image charge from the photodiode. The image sensor also includes a storage gate electrically coupled to the transfer gate to receive the image charge from the transfer gate. The storage gate has a gate electrode disposed proximate to a frontside of the semiconductor material, an optical shield disposed in the semiconductor material, and a storage node disposed between the gate electrode and the optical shield. The optical shield is optically aligned with the storage node to prevent the image light incident on the backside illuminated image sensor from reaching the storage node.

A complementary metal-oxide-semiconductor depth sensor element comprises a photogate formed in a photosensitive area on a substrate. A first transfer gate and a second transfer gate are formed respectively on two sides of the photogate in intervals. A first floating doped area and a second floating doped area are formed respectively on the outer sides of the first transfer gate and the second transfer gate. The first and second floating doped regions have dopants of a first polarity and the semiconductor area has dopants of a second polarity opposite to the first polarity. Since the photogate and at least parts of the first and second transfer gates connect to the same semiconductor area and no other dopants of polarity opposite to the second polarity. Therefore, the majority carriers from the photogate excited by lights drift, but not diffuse, to transfer to the first and second transfer gates.