Method of manufacturing image sensor including nanostructure color filter
A method of manufacturing an image sensor includes: preparing a sensor substrate including: a sensor layer including a photosensitive cell; and a signal line layer including lines to receive electric signals from the photosensitive cell; forming a first material layer having a first refractive index on the sensor substrate; and forming a nanopattern layer on the first material layer, the nanopattern layer including a material having a second refractive index different from the first refractive index.
1. A method of manufacturing an image sensor, the method comprising:
preparing a sensor substrate comprising:
a sensor layer comprising a photosensitive cell that receives light and generates electric signals; and
a signal line layer comprising lines to receive the electric signals from the photosensitive cell;
forming a first material layer having a first refractive index on the sensor substrate; and
forming a nanopattern layer on the first material layer, the nanopattern layer comprising a material having a second refractive index greater than the first refractive index,
wherein the sensor layer is disposed between the signal line layer and the first material layer.
2. The method of claim 1 , wherein the forming the nanopattern layer comprises:
bonding a first substrate having the second refractive index to the first material layer;
forming a second material layer having a predetermined thickness by reducing a thickness of the first substrate; and
patterning the second material layer to form a plurality of nanostructures on the first material layer.
3. The method of claim 2 , wherein the patterning the second material layer comprises forming a plurality of regions in which at least one of a shape of the plurality of nanostructures and a pitch of adjacent nanostructures of the plurality of nanostructures is adjusted.
4. The method of claim 2 , wherein the first material layer comprises a silicon oxide layer, and
wherein the first substrate comprises a silicon substrate.
5. The method of claim 4 , wherein the bonding the first substrate is performed by an anodic bonding method.
6. The method of claim 2 , wherein the reducing the thickness of the first substrate comprises reducing the thickness of the first substrate by a chemical mechanical polishing (CMP) method.
7. The method of claim 2 further comprising forming a weak region in the first substrate by implanting ions into the first substrate prior to the bonding the first substrate.
8. The method of claim 7 , wherein the thickness of the first substrate is reduced by a layer splitting method.
9. The method of claim 2 , wherein the first substrate comprises a silicon-on-insulator (SOI) substrate, and
wherein the SOI substrate comprises a first silicon layer, a second silicon layer and a silicon oxide layer provided between the first and the second silicon layers.
10. The method of claim 9 , wherein the reducing the thickness of the first substrate comprises removing the second silicon layer and the silicon oxide layer.
11. The method of claim 1 , wherein the forming the nanopattern layer comprises:
forming a plurality of nanostructures on a second substrate; and
transferring the plurality of nanostructures on the second substrate to the first material layer.
12. The method of claim 11 , further comprising forming a plurality of nanoribbons by underetching a surface of the second substrate, the underetched surface being in contact with the plurality of nanostructures.
13. The method of claim 12 , wherein the plurality of nanostructures are transferred to the first material layer using a viscoelastic polymer.
14. The method of claim 2 , wherein the bonding the first substrate is performed by a polymer bonding method.
15. A method of manufacturing an image sensor, the method comprising:
preparing an SOI substrate comprising a first silicon layer, second silicon layer and a silicon oxide layer provided between the first and the second silicon layers;
forming a sensor layer comprising at least one photosensitive cell by processing the second silicon layer;
forming lines on the sensor layer to receive electric signals from the at least one photosensitive cell;
forming a protective layer on the sensor layer to cover the lines;
bonding a first substrate to the protective layer;
reducing a thickness of the first silicon layer; and
patterning the first silicon layer to form a nanopattern layer comprising a plurality of nano structures.
16. The method of claim 15 , wherein the patterning the first silicon layer comprises forming a plurality of regions in which at least one of a shape of the plurality of nanostructures and a pitch of adjacent nanostructures of the plurality of nanostructures repeatedly arranged is adjusted.
17. The method of claim 15 , wherein the protective layer comprises a silicon oxide.
18. The method of claim 17 , wherein the first substrate comprises a silicon substrate.
19. The method of claim 18 , wherein the bonding the first substrate to the protective layer is performed by an anodic bonding method.
20. The method of claim 15 , wherein the bonding the first substrate to the protective layer is performed by a polymer bonding method using a polymer layer provided between the first substrate and the protective layer.
21. The method of claim 15 , wherein the protective layer comprises a polymer, and
wherein the bonding the first substrate to the protective layer is performed by a polymer bonding method.
22. The method of claim 15 , wherein the bonding the first substrate to the protective layer is performed by a metal bonding method using a metal layer provided between the first substrate and the protective layer.