Image sensor

An image senor, comprising:

• a pixel array in which a plurality of pixels having photoelectric conversion elements are arranged in a matrix in a first direction and a second direction intersecting the first direction;
• first to third color filters corresponding to the plurality of pixels, the first to third color filters configured to transmit light of sequentially longer wavelengths, such that
• the second color filter is configured to selectively transmit a longer wavelength than the first color filter, and
• the third color filter is configured to selectively transmit a longer wavelength than the second color filter;
• and
• first to third microlenses, respectively on the first to third color filters, the first to third microlenses configured to condense lights incident on the pixels through the first to third color filters,
• wherein each microlens of the first to third microlenses, when viewed in a cross-section passing through a center of a corresponding pixel and taken in a direction parallel to the first direction, have an asymmetric shape with respect to a line passing through the center of the corresponding pixel,
• wherein each microlens of the first to third microlenses has a respective uppermost point that is a point of the microlens protruding furthest in a third direction perpendicular to the first and second directions, and heights of respective uppermost points of the first to third microlenses in the third direction increase sequentially, such that
• a height of an uppermost point of the second microlens is greater than a height of an uppermost point of the first microlens, and
• a height of an uppermost point of the third microlens is greater than the height of the uppermost point of the second microlens, and
• wherein the pixel array is in a pixel region, and a distance between the respective uppermost point of each microlens of the first to third microlenses and a center of a respective pixel corresponding to the microlens increases in an outward direction toward an edge portion of the pixel region from a central portion of the pixel region.

A method of manufacturing an image sensor, the image sensor comprising a pixel array in which a plurality of pixels having photoelectric conversion elements are arranged in a matrix in a first direction and a second direction intersecting the first direction, color filters provided to correspond to the pixels and having at least two types of different colors, and microlenses provided on the color filters to condense lights incident on the pixels through the color filters, the method comprising:

• forming a planarization layer on the color filters, the planarization formed of a microlens material;
• providing a photoresist on the planarization layer, the photoresist having an asymmetrical shape;
• reflowing the photoresist;
• and
• etching the planarization layer using the reflowed photoresist as a mask.