Image sensors

An image sensor, comprising:

• an isolation layer disposed in a substrate and surrounding at least partially a photo conversion region;
• a grid pattern disposed over the isolation layer and including a upper portion and a lower portion being contact with the upper portion;
• a refractive fence disposed on and being contact with the upper portion;
• a color filter surrounded by the grid pattern and the refractive fence;
• and
• a micro-lens on the color filter,
• wherein the upper portion of the grid pattern and the lower portion of the grid pattern includes different metal materials,
• wherein a height of the refraction fence is at least half the height of the color filter, and
• wherein a height of the grid pattern is less than half the height of the color filter.

A manufacturing method of an image sensor, comprising:

• providing a semiconductor substrate;
• forming an internal structural features in the substrate, the internal structural features including a plurality of pixels and a and a isolation layer defining and isolating each pixels;
• forming a interconnect line structure on a first surface the substrate;
• forming a first metal layer, a second metal layer, a hardmask layer and a photomask pattern sequentially on a second surface of the semiconductor substrate opposed to the first surface of the semiconductor substrate;
• forming a hardmask pattern by etching the hardmask layer using the photomask pattern as a first etching mask;
• removing the photomask pattern;
• forming a grid pattern by etching the first and second metal layers using the hardmask pattern as a second etching mask;
• and
• forming a color filter such that at least part of the color filter is surrounded by the grid pattern, and
• wherein the grid pattern includes a top portion formed from the second metal layer and a bottom portion formed from the first metal layer, the top portion is being contact with the bottom portion and the second metal layer includes a metal material different from that of the first metal layer.