An imaging device capable of obtaining high-quality imaging data is provided. The imaging device can correct variation in the threshold voltage of amplifier transistors included in pixel circuits. The amplifier transistor includes two gates facing each other with a channel formation region provided therebetween. The amplifier transistor operates in such a manner that one of the gates holds a potential for correcting variation in the threshold voltage and the other thereof is supplied with a potential corresponding to imaging data.

A solid state imaging device according to the invention includes: a semiconductor layer of a first conductivity type; a gate insulation film that is located on the semiconductor layer; a gate electrode that is located on the gate insulation film; a first impurity region of a second conductivity type that is located at least in a region outside the gate electrode on a first end portion side; a second impurity region of the second conductivity type that is located in a region extending across a second end portion that is opposite to the first end portion of the gate electrode; and a third impurity region of the first conductivity type that is located on top of the second impurity region at a position outside the gate electrode on the second end portion side, and is in contact with the second impurity region.

A minute transistor is provided. A transistor with low parasitic capacitance is provided. A transistor having high frequency characteristics is provided. A semiconductor device including the transistor is provided. The semiconductor device includes an oxide semiconductor; a second insulator; a first conductor and a first insulator that are embedded in the second insulator; a second conductor; a third conductor; and a third insulator covering the oxide semiconductor. The oxide semiconductor includes a region where an angle formed between a plane that is parallel to a bottom surface of the oxide semiconductor and the side surface of the oxide semiconductor is greater than or equal to 30 and less than or equal to 60.

Various embodiments of the present disclosure are directed towards an integrated chip including a photodetector in a substrate. A gate electrode comprises a first segment on a first surface of the substrate and a second segment in the substrate and adjacent to the photodetector. The first segment contacts a first region of the second segment and is laterally offset from a second region of the second segment. In top view a first area of the first segment is greater than a second area of the second region of the second segment.

An image sensor device includes a digital pixel that includes a photo detector, a comparator, and a memory circuit, a pixel driver that controls the digital pixel, and a digital logic circuit that performs a digital signal processing operation on a digital signal output from the digital pixel. The photo detector and a first portion of the comparator are formed in a first semiconductor die, a second portion of the comparator, the memory circuit, and the pixel driver are formed in a second semiconductor die under the first semiconductor die, and the digital logic circuit is formed in a third semiconductor die under the second semiconductor die.

A pixel layout is optimized. An amplification unit generates a signal corresponding to a charge held in a charge holding unit and outputs the signal to a predetermined first output node. A first capacitive element has one end connected to the first output node and holds a reset level that is a level of the signal at the time of resetting. A second capacitive element has one end connected to the first output node and holds an image signal level that is a level of the signal when the charge is transferred to the charge holding unit. A readout circuit is connected to a second output node, reads each of the reset level held in the first capacitive element and the image signal level held in the second capacitive element, and outputs the reset level and the image signal level as a reset signal and an image signal, respectively.

Some embodiments relate to an image sensor pixel comprising a transfer gate formed on a first surface of a semiconductor substrate, a floating diffusion formed in the first surface of the semiconductor substrate, and a buried-well vertically pinned photodiode having a charge accumulation/storage region disposed substantially beneath the transfer gate. The transfer gate is spaced away from the floating diffusion such that an intervening semiconductor region provides a potential barrier to charge flow from beneath the transfer gate to the floating diffusion. The transfer gate is operable to control a vertical pump gate to selectively transfer charge from the charge accumulation/storage region to the floating diffusion by pumping charge from the buried charge accumulation/storage region underlying the transfer gate, over the potential barrier, and out to the floating diffusion, such that full charge transfer can be achieved without overlapping the edge of the transfer gate with the floating diffusion.

An imaging device whose dynamic range is broadened is provided. The imaging device includes a pixel including a first photoelectric conversion element and a first circuit including a second photoelectric conversion element. The first circuit switches the operation mode of the pixel to a normal imaging mode or a wide dynamic range mode and switches the operation region of the first photoelectric conversion element to a normal region or an avalanche region in accordance with the illuminance of light with which the second photoelectric conversion element is irradiated. When the illuminance of light with which the first photoelectric conversion element is irradiated is increased, the increase rate of a writing current flowing to the pixel is higher in the avalanche region than in the normal region. However, in the wide dynamic range mode, the increase rate of current can be lowered, and thus the dynamic range can be broadened.

An image pickup device capable of completely transmit charges generated at a photodiode to a floating diffusion region is provided. In a pixel region, a plurality of fin-like structures are so formed as to loin a photodiode formation region with the floating diffusion region. In the fin-like structure, a depth from a surface of a P type well to a predetermined position of depth is defined as a height. Having the height and a width, the fin-like structure extends in a direction intersecting a direction in which a gate electrode extends. The gate electrode of a transfer transistor is so formed as to cover opposing side surfaces and an upper surface of each fin-like structure.

An object is to provide a structure of a transistor which has a channel formation region formed using an oxide semiconductor and a positive threshold voltage value, which enables a so-called normally-on switching element. The transistor includes an oxide semiconductor stack in which at least a first oxide semiconductor layer and a second oxide semiconductor layer with different energy gaps are stacked and a region containing oxygen in excess of its stoichiometric composition ratio is provided.