Image sensor

An image sensor comprising:

• a pixel;
• a first device isolation layer extending around the pixel;
• and
• a second device isolation layer extending along an inner side of the first device isolation layer and separating a first active region, a second active region, and a third active region of a semiconductor substrate in the pixel from one another, and
• wherein the pixel comprises a floating diffusion region and a photoelectric converter disposed in the first active region as spaced apart from each other,
• a ground region,
• a gate of a transfer transistor disposed in the first active region between the floating diffusion region and the photoelectric converter, and
• at least one other transistor integrated in a circuit with the transfer transistor, the at least one other transistor including source and drain regions, and
• wherein the ground region is disposed in the second active region,
• the ground region is electrically connected to a ground voltage terminal, and
• the source and drain regions of the at least one other transistor are disposed in the third active region.

An image sensor comprising:

• a plurality of pixels;
• a first device isolation layer extending around each of the pixels so as to separate the pixels from each other;
• and
• a second device isolation layer, and
• wherein both the first device isolation layer and the second device isolation layer extend into the semiconductor substrate in a direction from a front surface of the substrate towards a back surface of the substrate, the first device isolation layer extends deeper into the semiconductor substrate than the second device isolation layer from the front surface of the semiconductor substrate, and the second device isolation layer separates a plurality of active regions of the substrate, at a front side of the semiconductor substrate, from each other in each of the pixels,
• each of the pixels has a floating diffusion region and a ground region of first and second conductivity types, respectively, a photoelectric converter region of the first conductivity type, a gate electrode extending into one of the active regions of the semiconductor substrate, and a plurality of transistors,
• the floating diffusion region and the ground region are each located in one of the active regions,
• the plurality of transistors are located at another of the plurality of active regions separated by the second device isolation layer from the active region or regions into which the gate electrode extends and in which the floating diffusion and ground regions are located,
• the photoelectric converter region constitutes a photoelectric converter that converts external light to charges, and
• the gate electrode constitutes a transfer transistor that transfers charges that have accumulated in the photoelectric converter.