Image sensor

An image sensor, comprising:

• a substrate having a first surface and a second surface opposite to the first surface, the substrate including first to third unit pixels arranged in a first direction, the first direction extending parallel to the second surface of the substrate;
• a first pixel separation portion in the substrate and between the first unit pixel and the second unit pixel to separate the first and second unit pixels from each other;
• and
• a second pixel separation portion in the substrate and between the second unit pixel and the third unit pixel to separate the second and third unit pixels from each other,
• wherein the first pixel separation portion includes
• a first conductive pattern, and
• a first separation insulating pattern covering a sidewall of the first conductive pattern,
• wherein the second pixel separation portion includes a second separation insulating pattern and excludes the first conductive pattern, and
• wherein the first pixel separation portion has a first width in the first direction, and the second pixel separation portion has a second width in the first direction, the second width being less than the first width.

An image sensor, comprising:

• a substrate having a first surface and a second surface opposite to the first surface, the substrate including first to third unit pixels arranged in a first direction, the first direction extending parallel to the second surface of the substrate;
• a transfer gate on the first surface of the substrate in each of the first to third unit pixels:
• a first interlayer insulating layer covering the first surface of the substrate;
• a first pixel separation portion in the substrate and between the first unit pixel and the second unit pixel to separate the first and second unit pixels from each other;
• a second pixel separation portion in the substrate and between the second unit pixel and the third unit pixel to separate the second and third unit pixels from each other;
• a first light blocking pattern on the second surface of the substrate and overlapping the first pixel separation portion in a vertical direction extending perpendicular to the second surface of the substrate;
• and
• a second light blocking pattern on the second surface of the substrate and overlapping the second pixel separation portion in the vertical direction,
• wherein the first pixel separation portion includes
• a first conductive pattern,
• a first separation insulating pattern covering a sidewall of the first conductive pattern, and
• a first filling insulation pattern between the first conductive pattern and the first interlayer insulating layer,
• wherein the second pixel separation portion includes
• a second conductive pattern,
• a second separation insulating pattern covering a sidewall of the second conductive pattern, and
• a second filling insulation pattern between the second conductive pattern and the first interlayer insulating layer,
• wherein the first pixel separation portion has a first width in the first direction, and the second pixel separation portion has a second width in the first direction, the second width being less than the first width,
• wherein the first light blocking pattern has a third width in the first direction, and
• wherein the second light blocking pattern has a fourth width in the first direction, the fourth width being less than the third width.