Image sensor and method of manufacturing the same

An image sensor comprising:

• a substrate including unit pixels and including a first surface and a second surface which is opposite to the first surface;
• a pixel isolation portion provided in the substrate to isolate the unit pixels from each other;
• photoelectric conversion portions provided in the substrate, corresponding to the unit pixels, respectively;
• a transfer gate provided on the first surface, corresponding to each unit pixel of the unit pixels;
• a fixed charge layer contacting the second surface;
• a color filter array provided on the fixed charge layer;
• and
• a micro lens array layer on the color filter array,
• wherein the pixel isolation portion comprises:
• a first filling insulation pattern extending from the first surface toward the second surface and including an air gap region, the first filling insulation pattern including a first sidewall and a second sidewall which is opposite to the first sidewall;
• and
• a conductive structure comprising:
• a first portion on the first sidewall;
• and a second portion on the second sidewall,
• wherein a portion of the fixed charge layer protrudes toward the air gap region.

An image sensor comprising:

• a substrate including a first surface and a second surface which is opposite to the first surface;
• and
• a pixel isolation portion provided in the substrate and configured to isolate a first unit pixel from a second unit pixel,
• wherein the pixel isolation portion comprises:
• a first filling insulation pattern extending from the first surface toward the second surface and including an air gap region, the first filling insulation pattern including a first sidewall and a second sidewall which is opposite to the first sidewall;
• a conductive structure including a first portion on the first sidewall;
• a second portion on the second sidewall;
• and a connection portion connecting the first portion and the second portion;
• and
• an insulating liner provided between the first portion and the substrate and provided between the second portion and the substrate,
• wherein the image sensor further comprises a fixed charge layer covering the second surface,
• wherein a portion of the fixed charge layer protrudes toward the air gap region, and
• wherein a density of an insulating material included in the insulating liner is greater than a density of an insulating material included in the first filling insulation pattern.