Image sensor and method of fabricating the same

1. A method for fabricating an image sensor, the method comprising:

forming a lower structure having a photodiode and an interconnection;

forming a passivation layer on the lower structure, wherein forming the passivation layer comprises forming an oxide layer on the lower structure, forming a nitride layer on the oxide layer, annealing the nitride layer in a reducing atmosphere, and exposing the oxide layer by removing the nitride layer;

forming a color filter array on the passivation layer;

forming a micro-lens array on the color filter array;

forming a Low Temperature Oxide (LTO) layer on the micro-lens array; and

exposing a pad section on the lower structure by etching the LTO layer and the passivation layer.

2. The method as claimed in claim 1 , further comprising forming a thermo-setting resin layer on the exposed oxide layer.

3. The method as claimed in claim 1 , wherein the nitride layer is removed using an etch back method.

4. The method as claimed in claim 1 , wherein the LTO layer has a thickness of 3,000 Å to 8,000 Å.

5. The method as claimed in claim 1 , wherein the LTO layer is deposited conformally on the micro-lens array such that it has a zero gap.

6. The method as claimed in claim 1 , wherein forming the LTO layer comprises depositing the LTO layer by plasma-enhanced chemical vapor deposition (PECVD).

7. The method as claimed in claim 1 , wherein forming the micro-lens array comprises patterning a micro-lens material layer, and then heating a resultant structure at a temperature of 150° C. to 180° C. for 2 to 3 hours.

8. The method as claimed in claim 7 , wherein the heating is performed in a convection oven.

9. A method for fabricating an image sensor, the method comprising:

forming a lower structure having a photodiode and an interconnection;

forming a passivation layer on the lower structure, wherein forming the passivation layer comprises forming an oxide layer on the lower structure, forming a nitride layer on the oxide layer, annealing the nitride layer in a reducing atmosphere, and exposing the oxide layer by removing the nitride layer;

forming a thermo-setting resin layer on the passivation layer;

forming a color filter array on the thermo-setting resin layer;

forming a micro-lens array on the color filter array;

forming a Low Temperature Oxide (LTO) layer on the micro-lens array; and

exposing a pad section on the lower structure by etching the LTO layer and the passivation layer.

10. The method as claimed in claim 9 , wherein the nitride layer is removed using an etch back method.

11. The method as claimed in claim 9 , wherein the LTO layer has a thickness of 3,000 Å to 8,000 Å.

12. The method as claimed in claim 9 , wherein forming the LTO layer comprises conformal deposition on the micro-lens array such that it has a zero gap.

13. The method as claimed in claim 9 , wherein forming the LTO layer comprises depositing the LTO layer by plasma-enhanced chemical vapor deposition (PECVD).

14. The method as claimed in claim 9 , wherein forming the micro-lens array comprises patterning a micro-lens material layer, and then heating a resultant structure at a temperature of 150° C. to 180° C. for 2 to 3 hours.

15. The method as claimed in claim 6 , wherein the LTO layer is formed from a silicon-containing precursor selected from the group consisting of a silane and TEOS, and an oxygen precursor selected from the group consisting of dioxygen and ozone.

16. The method as claimed in claim 13 , wherein the LTO layer is formed from a silicon-containing precursor selected from the group consisting of a silane and TEOS, and an oxygen precursor selected from the group consisting of dioxygen and ozone.

17. The method as claimed in claim 1 , wherein the color filter array comprises an array of red, green and blue filters or yellow, cyan and magenta filters, and each filter in the color filter array comprises a resist material and a dye that absorbs predetermined wavelengths of light corresponding to a color of the filter.

18. The method as claimed in claim 13 , wherein the color filter array comprises an array of red, green and blue filters or yellow, cyan and magenta filters, and each filter in the color filter array comprises a resist material and a dye that absorbs predetermined wavelengths of light corresponding to a color of the filter.

19. The method as claimed in claim 1 , further comprising forming a photoresist pattern on the LTO layer before etching the LTO layer and the passivation layer, then removing the photoresist pattern.

20. The method as claimed in claim 13 , further comprising forming a photoresist pattern on the LTO layer before etching the LTO layer and the passivation layer, then removing the photoresist pattern.