The present technology relates to a solid-state imaging device and an electronic device for increasing the degree of freedom regarding arrangement of transistors. Provided are a photoelectric conversion unit, a trench penetrating a semiconductor substrate in a depth direction and formed between the photoelectric conversion units respectively formed in adjacent pixels, and a PN junction region configured by a P-type region and an N-type region on a sidewall of the trench, in which a part of sides surrounding the photoelectric conversion unit includes a region where the P-type region is not formed or a region where the P-type region is thinly formed. The PN junction region is formed on at least one side of four sides surrounding the photoelectric conversion unit, and the P-type region is not formed on the remaining sides. The present technology can be applied to, for example, a back-illuminated-type CMOS image sensor.

Provided are a light-receiving element which has more capability of detecting wavelengths than that of existing silicon light-receiving elements and a unit pixel of an image sensor by using it. The light-receiving element includes: a light-receiving unit which is floated or connected to external voltage and absorbs light; an oxide film which is formed to come in contact with a side of the light-receiving unit; a source and a drain which stand off the light-receiving unit with the oxide film in between and face each other; a channel which is formed between the source and the drain and forms an electric current between the source and the drain; and a wavelength expanding layer which is formed in at least one among the light-receiving unit, the oxide film and the channel and forms a plurality of local energy levels by using strained silicon.

An infrared solid state imaging device includes: a first PN junction diode has a first shortest length that is a shortest length from a first junction surface to a second junction surface; a PN junction diode has a second shortest length that is a shortest length from the second junction surface to a third junction surface, the second shortest length being different from the first shortest length; an insulating film serving as an element isolation region which establishes electrical isolation between a first region of the first PN junction diode and a fourth region of the second PN junction diode, and so on; and a metal wire provided on a second region of the first PN junction diode and a third region of the second PN junction diode, wherein the first PN junction diode and the second PN junction diode are connected in series.

Provided are a light-receiving element which has more capability of detecting wavelengths than that of existing silicon light-receiving elements and a unit pixel of an image sensor by using it. The light-receiving element includes: a light-receiving unit which is floated or connected to external voltage and absorbs light; an oxide film which is formed to come in contact with a side of the light-receiving unit; a source and a drain which stand off the light-receiving unit with the oxide film in between and face each other; a channel which is formed between the source and the drain and forms an electric current between the source and the drain; and a wavelength expanding layer which is formed in at least one among the light-receiving unit, the oxide film and the channel and forms a plurality of local energy levels by using strained silicon.

A solid-state imaging device includes a plurality of pixels, each of the plurality of pixels including a photoelectric converter. The photoelectric converter includes a first semiconductor region of a first conductivity type, a second semiconductor region of a second conductivity type provided under the first semiconductor region, and a third semiconductor region of the first conductivity type provided under the second semiconductor region. The second semiconductor region has a first end portion and a second end portion opposing to the first end portion. The third semiconductor region has a first region and a second region overlapping with the second semiconductor region in a plan view, and the first region and the second region are spaced apart from each other from a part of the first end portion to a part of the second end portion.

A solid-state imaging device includes a plurality of pixels, each of the plurality of pixels including a photoelectric converter. The photoelectric converter includes a first semiconductor region of a first conductivity type, a second semiconductor region of a second conductivity type provided under the first semiconductor region, and a third semiconductor region of the first conductivity type provided under the second semiconductor region. The second semiconductor region has a first end portion and a second end portion opposing to the first end portion. The third semiconductor region has a first region and a second region overlapping with the second semiconductor region in a plan view, and the first region and the second region are spaced apart from each other from a part of the first end portion to a part of the second end portion.

Image sensors may include backside illuminated global shutter pixels that are implemented using stacked substrates. To provide high dynamic range in the pixels, only a predetermined portion of charge that has been generated in the pixel photodiodes is kept and stored in the pixel photodiodes when the pixels are illuminated by high light levels. In the low light level illumination conditions, all of the accumulated charge is stored in the pixel photodiodes, thereby preserving high sensitivity and low noise. Dynamic charge overflow may be used to increase the high dynamic range. To achieve low noise operation in a global shutter scanning mode, dynamic charge overflow may be combined with correlated double sampling techniques.

Provided are a light-receiving element which has more capability of detecting wavelengths than that of existing silicon light-receiving elements and a unit pixel of an image sensor by using it. The light-receiving element includes: a light-receiving unit which is floated or connected to external voltage and absorbs light; an oxide film which is formed to come in contact with a side of the light-receiving unit; a source and a drain which stand off the light-receiving unit with the oxide film in between and face each other; a channel which is formed between the source and the drain and forms an electric current between the source and the drain; and a wavelength expanding layer which is formed in at least one among the light-receiving unit, the oxide film and the channel and forms a plurality of local energy levels by using strained silicon.

Some embodiments provide an image sensor pixel comprising a junction field effect transistor (JFET) and a floating diffusion configured to act as the gate of the JFET. An image sensor may comprise a plurality of pixels, at least one pixel comprising floating diffusion region formed in a semiconductor substrate, a transfer gate configured to selectively cause transfer of photocharge stored in the pixel to the floating diffusion, and a JFET having (i) a source and a drain coupled by a channel region, and (ii) a gate comprising the floating diffusion region.

An imaging device includes: a semiconductor layer including a first region of a first conductivity, a second region of a second conductivity opposite to the first conductivity, and a third region of the second conductivity; a photoelectric converter electrically connected to the first region and converting light into charge; a first transistor including a first source, a first drain, and a first gate above the second region, the first region corresponding to the first source or drain; and a second transistor including a second source, a second drain, and a second gate of the second conductivity above the third region, the first region corresponding to the second source or drain, and the second gate being electrically connected to the first region. The concentration of an impurity of the second conductivity in the third region is higher than that of an impurity of the second conductivity in the second region.