Image sensors and methods of manufacturing the same

An image sensor comprising:

• a semiconductor substrate having a first surface, a second surface, and a recess portion, the second surface opposite the first surface, and the recess portion extending inward towards the semiconductor substrate from the second surface;
• a plurality of photoelectric conversion devices included in the semiconductor substrate;
• a conductive layer on a second surface of the semiconductor substrate;
• a conductive pad in contact with the conductive layer in the recess portion;
• a first passivation layer on a portion of the second surface of the semiconductor substrate, a side surface of the recess portion, a portion of a bottom surface of the recess portion, and a side surface of the conductive pad;
• and
• a second passivation layer on an upper surface of the first passivation layer and at least a portion of the first passivation layer in the recess portion,
• wherein
• the conductive layer extends between the first passivation layer and the second surface of the semiconductor substrate, between the first passivation layer and a side surface of the recess portion, between the first passivation and a portion of the bottom surface of the recess portion, and between a lower surface of the conductive pad and a portion of the bottom surface of the recess portion.

An image sensor comprising:

• a chip structure, the chip structure including a first region and a second region,
• wherein
• the chip structure further comprises,
• an upper substrate having a first surface, a second surface, and a recess portion, the second surface opposite the first surface, and the recess portion recessed from the second surface in the second region;
• a plurality of photoelectric conversion devices included in the upper substrate in the first region;
• a horizontal insulating layer on the second surface of the upper substrate;
• a conductive layer on a side surface and a bottom surface of the recess portion and at least a portion of the horizontal insulating layer in the second region;
• at least one conductive pad in contact with the conductive layer in the recess portion;
• a first passivation layer on a side surface of the conductive layer in the recess portion and the conductive layer on the horizontal insulating layer;
• and
• a second passivation layer on a side surface of the first passivation layer in the recess portion, and
• the second passivation layer includes a first protrusion extended toward the first passivation layer from the side surface of the first passivation layer, the second passivation layer including a material having a step coverage higher than a step coverage of a material of the first passivation.