A semiconductor device includes a photodiode, a first transistor, and a second transistor. The photodiode has a function of supplying a charge corresponding to incident light to a gate of the first transistor, the first transistor has a function of accumulating the charge supplied to the gate, and the second transistor has a function of retaining the charge accumulated in the gate of the first transistor. The second transistor includes an oxide semiconductor.

A semiconductor device includes a photodiode, a first transistor, and a second transistor. The photodiode has a function of supplying a charge corresponding to incident light to a gate of the first transistor, the first transistor has a function of accumulating the charge supplied to the gate, and the second transistor has a function of retaining the charge accumulated in the gate of the first transistor. The second transistor includes an oxide semiconductor.

An electrowetting element comprising a photosensor. The photosensor comprises a photosensitive material overlapped by an electrowetting element electrode; a first photosensor contact in contact with the photosensitive material; and a second photosensor contact in contact with the photosensitive material.

A photosensor including first and second conductive layers disposed on a main surface and a back surface of a substrate is provided. A conductive via layer is disposed between the conductive layers. A light emitting element and an integrated circuit (IC) including a light receiving element are mounted on the first conductive layer. The photosensor includes a translucent covering member that covers the light emitting element and the IC together with the first conductive layer. The covering member includes a groove between the light emitting element and the IC in a plan view. The first conductive layer includes a first mounting portion on which the light emitting element is mounted and a second mounting portion on which the IC is mounted. The light emitting device is electrically connected to the IC via the first mounting portion, the conductive via layer, the second conductive layer and the second mounting portion.

Provided is a gas sensor that can suppress characteristic variation caused by deformation of a semiconductor substrate. The gas sensor (1) includes a substrate (redistribution layer 30), a light-emitting element (11) provided at a front surface (30a) or embedded in the substrate, a light-receiving element (12) that is provided at the front surface or embedded in the substrate and that receives light emitted from the light-emitting element, and a plurality of external connection terminals (40) at a rear surface (30b) that is an opposite surface to the front surface of the substrate. At least a portion of the plurality of external connection terminals is electrically connected to the light-emitting element and the light-receiving element. The plurality of external connection terminals is arranged such that, in plan view, the light-emitting element and the light-receiving element are not present on a line linking any two external connection terminals.