Commissariat a L'energie Atomique Et Aux Energies Alternatives

Stmicroelectronics S.a.

Stmicroelectronics (crolles 2) Sas

Stmicroelectronics (crolles 2) Sas; Stmicroelectronics Sa

Commissariat À L'énergie Atomique Et Aux Énergies Alternatives

Stmicroelectronics (grenoble 2) Sas

Sebastien Jouan

Michel Marty

Laurent Frey

Salim Boutami

Didier Dutartre

A photodiode includes at least one central pad arranged on a light-receiving surface of a photodiode semiconductor substrate. The pad is made of a first material and includes lateral sidewalls surrounded by a spacer made of a second material having a different optical index than the first material. The lateral dimensions of the pad are smaller than an operating wavelength of the photodiode. Both the first and second materials are transparent to that operating wavelength. The pads and spacers are formed at a same time gate electrodes and sidewall spacers of MOS transistors are formed.

Photodiode of high quantum efficiency

A SPAD-type photodiode has a semiconductor substrate with a light-receiving surface. A lattice formed of interlaced strips made of a first material covers the light receiving surface. The lattice includes lattice openings with lateral walls covered by a spacer made of a second material. Then first and second materials have different optical indices, and further each optical index is less than or equal to the substrate optical index. A pitch of the lattice is of the order of a magnitude of an operating wavelength of the photodiode. The first and second materials are transparent at that operating wavelength. The lattice is made of a conductive material electrically coupled to an electrical connection node (for example, a bias voltage node).

Spad photodiode of high quantum efficiency

An integrated circuit includes a substrate and an interconnect part above the substrate, and further includes a photosensitive region in the substrate. A filter is provided aligned with the photosensitive region. The filter is formed by at least one layer of filter material. In one implementation for front side illumination, the layer of filter material is positioned above the photosensitive region between the interconnect part and the substrate. In another implementation for back side illumination, the layer of filter material is positioned below the photosensitive region opposite the interconnect part. The layer of filter material is configured such that a product of the thickness of the layer of filter material and the imaginary part of the refractive index of the layer of filter material is above 1 nm.

Method for producing an optical filter in an integrated circuit, and corresponding integrated circuit

A device and corresponding fabrication method includes a vertical stack having an intermediate layer between a lower region and an upper region. The intermediate layer is extended by a protection layer. The vertical stack has a free lateral face on which the lower region, the upper region and the protection layer are exposed.

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Crolles, France

Sebastien Jouan