Two-terminal electronic devices, such as photodetectors, photovoltaic devices and electroluminescent devices, are provided. The devices include a first electrode residing on a substrate, wherein the first electrode comprises a layer of metal; an I-layer comprising an inorganic insulating or broad band semiconducting material residing on top of the first electrode, and aligned with the first electrode, wherein the inorganic insulating or broad band semiconducting material is a compound of the metal of the first electrode; a semiconductor layer, preferably comprising a p-type semiconductor, residing over the I-layer; and a second electrode residing over the semiconductor layer, the electrode comprising a layer of a conductive material. The band gap of the material of the semiconductor layer, is preferably smaller than the band gap of the I-layer material. The band gap of the material of the I-layer is preferably greater than 2.5 eV.

An image pickup element 10 includes a first electrode 21, a charge accumulation electrode 24 that is arranged apart from the first electrode 21, a photoelectric conversion unit 23 that contacts the first electrode 21 and is formed above the charge accumulation electrode 24 via an insulation layer 82, and a second electrode 22 formed on the photoelectric conversion unit 23. The photoelectric conversion unit 23 includes, from the second-electrode side, a photoelectric conversion layer 23A, and an inorganic oxide semiconductor material layer 23B including In.sub.aGa.sub.bSn.sub.cO.sub.d, and 0.30≤b/(a+b+c)≤0.50 and b≥c are satisfied.

A solid-state imaging device includes a plurality of photoelectric converting units and a plurality of charge-accumulating units each accumulating a charge generated in the corresponding photoelectric converting unit. The photoelectric converting unit includes a photosensitive region that generates the charge in accordance with light incidence, and an electric potential gradient forming unit that accelerates migration of charge in a second direction in the photosensitive region. The charge-accumulating unit includes: a plurality of regions (semiconductor layers) having an impurity concentration gradually changed in one way in the second direction, and electrodes adapted to apply electric fields to the plurality of regions. Each of the electrodes is disposed over the plurality of regions having the impurity concentration gradually varied.

An imaging device includes a plurality of light-receiving elements arranged in a two-dimensional matrix shape. Each of the light-receiving elements includes a first electrode, a photoelectric conversion layer, and a second electrode. The photoelectric conversion layer has a laminated structure in which a first compound semiconductor layer having a first conductivity type and a second compound semiconductor layer having a second conductivity type that is a reverse conductivity type to the first conductivity type are laminated from a side of the first electrode. The second compound semiconductor layer has been removed in a region between the light-receiving elements. The first electrode and the first compound semiconductor layer are shared by the light-receiving elements. An impurity concentration of a first compound semiconductor layer near the first electrode is lower than that of a first compound semiconductor layer near the second compound semiconductor layer.

Provided is a solid-state imaging element including a plurality of pixels that includes at least two phase difference detection pixels for focus detection. Each pixel has a stacked structure including a plurality of photoelectric conversion elements that are stacked on top of each other and absorb light beams different in wavelength from one another to generate electrical charges, and each phase difference detection pixel includes, in the stacked structure, a color filter that partially covers an upper face of one of the photoelectric conversion elements and absorbs a light beam with a specific wavelength.

Imaging apparatus (2000, 2100, 2200) includes a photosensitive medium (2004, 2204) and an array of pixel circuits (302), which are arranged in a regular grid on a semiconductor substrate (2002) and define respective pixels (2006, 2106) of the apparatus. Pixel electrodes (2012, 2112, 2212) are connected respectively to the pixel circuits in the array and coupled to read out photocharge from respective areas of the photosensitive medium to the pixel circuits. The pixel electrodes in a peripheral region of the array are spatially offset, relative to the regular grid, in respective directions away from a center of the array.

An image sensor includes a sensor region for receiving light and generating an image data and a pad region adjacent to the sensor region, an insulation layer on the substrate, and a lower transparent electrode on the insulation layer in the sensor region, and an etch stop layer on the insulation layer in the sensor region and pad region. The etch stop layer may include silicon nitride. A height of an uppermost surface of the lower transparent electrode may be substantially equal to a height of an upper surface of the etch stop layer, with respect to the substrate.

A photosensing device with a photovoltage sensing mechanism, a graphene layer and a semiconductor layer. The graphene layer is sandwiched between the semiconductor layer and a substrate. The photovoltage sensing mechanism senses the photovoltage created by light impinging on the graphene-semiconductor heterojunction. The strength of the photovoltage is used to indicate the level of illumination of the impinging light.

A solid-state imaging device includes: a first electrode formed above a semiconductor substrate; a photoelectric conversion film formed on the first electrode and for converting light into signal charges; a second electrode formed on the photoelectric conversion film; a charge accumulation region electrically connected to the first electrode and for accumulating the signal charges converted from the light by the photoelectric conversion film; a reset gate electrode for resetting the charge accumulation region; an amplification transistor for amplifying the signal charges accumulated in the charge accumulation region; and a contact plug in direct contact with the charge accumulation region, comprising a semiconductor material, and for electrically connecting to each other the first electrode and the charge accumulation 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.