Antireflective coating composition based on silicon polymer

1. An antireflecting coating composition which is capable of forming a crosslinked coating underneath a layer of photoresist comprising a silicon polymer, where the silicon polymer comprises at feast one unit with the structure 1,

where, R 1 is selected from C 1 -C 4 alkyl, further where the silicon polymer comprises an absorbing chromophore capable of absorbing radiation used for exposing the photoresist, and further where the composition is free of units comprising Si—H and where the composition comprises a crosslinking catalyst.

2. The antireflecting coating composition of claim 1 , wherein the chromophore is selected from the group consisting of hydrocarbon aromatic rings, substituted phenyl, unsubstituted phenyl, substituted anthracyl, unsubstituted anthracyl, substituted phenanthracyl, unsubstituted phenanthracyl, substituted naphthyl, unsubstituted naphthyl, substituted heterocyclic aromatic rings, unsubstituted heterocyclic aromatic rings, and combinations thereof wherein the hetero atoms present in the hetero cyclic rings are selected from the group consisting of oxygen, nitrogen, sulfur and combinations thereof.

3. The antireflecting coating composition of claim 1 , where the absorbing chromophore has the structure 3,

where n=0-4.

4. The antireflecting coating composition of claim 1 , where the catalyst is selected from a photoacid generator, thermal acid generator and a salt.

5. The antireflecting coating composition of claim 1 , where the composition is free of units comprising Si-halogen.

6. The antireflecting coating composition of claim 1 , where the composition has less than 10 Si—OH per 100 Si atoms.

7. A process for forming an image comprising:

a) providing a coating of the coating composition of claim 1 on a substrate;

b) providing a photoresist layer;

c) imagewise exposing the top and bottom layer to actinic radiation of same wavelength;

d) postexposure baking the substrate,

e) developing the photoresist layer with an aqueous alkaline solution.

8. The process according to claim 7 , where the exposing actinic radiation has wavelength is in the range of 300 nm to 10 nm.

9. An antireflecting coating composition which is capable of forming a crosslinked coating underneath a layer of photoresist comprising a silicon polymer, where the silicon polymer comprises at least one unit with the structure 1,

where, R 1 is selected from C 1 -C 4 alkyl, further where the silicon polymer comprises an absorbing chromophore capable of absorbing radiation used for exposing the photoresist, and further where the composition is free of units comprising Si—H and where the composition further comprises a dye.

10. The antireflecting coating composition of claim 9 , where dye is a small molecule compound or an absorbing polymer.

11. The antireflecting coating composition of claim 10 , where the absorbing polymer comprises at least one a unit of structure 2,

where n=0-4.

12. The antireflecting coating composition of claim 9 , where the dye comprises a chromophore selected from hydrocarbon aromatic rings, substitute phenyl, unsubstituted phenyl, substituted anthracyl, unsubstituted anthracyl, substituted phenanthracyl, unsubstituted phenanthracyl, substituted naphthyl, unsubstituted naphthayl, substituted heterocyclic aromatic rings, unsubstituted heterocyclic aromatic rings, and combinations thereof wherein the hetero atoms present in the hetero cyclic rings are selected from the group consisting of oxygen, nitrogen, sulfur and combinations thereof.

13. The antireflecting coating composition of claim 9 , further comprising a crosslinking catalyst.

14. The antireflecting coating composition of claim 13 , where the catalyst is selected from a photoacid generator, thermal acid generator and a salt.