Image sensor and method for fabricating the same

An image sensor comprising:

• a substrate comprising a first side on which light is incident and a second side opposite to the first side;
• and
• a first separation pattern extending from the second side, the first separation pattern being interposed between a plurality of unit pixels in the substrate of a light-receiving region and a light-shielding region provided around the light-receiving region,
• wherein a first sub-trench which extends from the first side is formed in the substrate of the light-shielding region,
• a surface insulating film extends along the first sub-trench,
• a second sub-trench, which is formed in the substrate and extends from the first sub-trench, exposes the first separation pattern and the surface insulating film, and
• a contact film is provided on the surface insulating film, and extends along the first sub-trench and the second sub-trench to contact the first separation pattern.

An image sensor comprising:

• a first substrate comprising a first side on which light is incident and a second side opposite to the first side;
• a first separation pattern extending from the second side, the first separation pattern being interposed between a plurality of unit pixels in the first substrate of a light-receiving region and a light-shielding region provided around the light-receiving region;
• a second separation pattern extending from the first side and overlapping the first separation pattern, the second separation pattern being provided in the first substrate of the light-receiving region;
• a plurality of microlenses respectively corresponding to the plurality of unit pixels, the plurality of microlenses being provided on the first side of the first substrate;
• a first wiring structure comprising a first inter-wiring insulating film and a first wiring provided in the first inter-wiring insulating film, the first wiring structure being provided on the second side of the first substrate;
• a contact film extending from the first side and electrically connected to the first separation pattern, the contact film being provided in the first substrate of the light-shielding region;
• and
• a pad pattern exposed through the first side on the first substrate of a pad region provided around the light-receiving region.