Hardmask process for forming a reverse tone image using polysilazane

1. A process for forming a reverse tone image on a device comprising;

a) optionally, forming an absorbing organic underlayer on a substrate;

b) forming a coating of a photoresist over the underlayer;

c) forming a photoresist pattern having a width of the photoresist feature (D 1 );

d) forming a polysilazane coating over the photoresist pattern from a polysilazane coating composition, where the polysilazane coating is thicker than the photoresist pattern, and further where the polysilazane coating composition comprises a silicon/nitrogen polymer and an organic coating solvent;

e) etching the polysilazane coating to remove the polysilazane coating at least up to a level where the top of the photoresist pattern is revealed; and,

f) dry etching to remove the photoresist and the underlayer which is beneath the photoresist, thereby forming an opening (D 2 )beneath where the photoresist pattern was present,

further where the shrinkage%, {(D 1 -D 2 )/D 1 }*100, is in a range from about 5 to about 80.

2. The process of claim 1 , further comprising a step of dry etching the substrate.

3. The process of claim 1 , where the underlayer is present.

4. The process of claim 1 , where no underlayer is present.

5. The process of claim 1 where in step f) the dry etching comprises using the same gas composition to remove the photoresist and the underlayer in one continuous step.

6. The process of claim 1 where in step f) the dry etching comprises first removing the photoresist followed by a separate step to remove the underlayer.

7. The process of claim 1 where the polysilazane comprises at least one unit of structure ( 8 ),

wherein R 1 , R 2 , and R 3 are each independently selected from hydrogen, alkyl, alkenyl, cycloalkyl, aryl, fluoroalkyl, an alkylsilyl group, an alkylamino group, an alkoxy group, and n is an integer.

8. The process of claim 1 where the polysilazane comprises at least one unit of structure ( 8 ),

wherein R 1 , R 2 , and R 3 are each independently selected from hydrogen, alkyl, alkenyl, cycloalkyl, aryl, fluoroalkyl, an alkylsilyl group, an alkylamino group, an alkoxy group, n is an integer, and provided that at least one of R 1 , R 2 , and R 3 is a hydrogen atom.

9. The process of claim 1 where the polysilazane comprises at least one unit of structure ( 9 ),

where n is an integer.

10. The process of claim 1 , where the underlayer has a carbon content greater than 75 weight%.

11. The process of claim 1 , where the imagewise exposure is selected from 248 nm, 193 nm, 157 nm, EUV, e-beam, and imprinting.

12. The process of claim 1 , where the dry etching gas in step e) for removing the silicon layer comprises a fluorocarbon.

13. The process of claim 1 , where the dry etching gas in step f) comprises oxygen.

14. A product formed by using the process of claim 1 .

15. A microelectronic device formed by using a process for forming a reverse tone image on a device comprising;

a) optionally, forming an absorbing organic underlayer on a substrate;

b) forming a coating of a photoresist over the underlayer;

c) forming a photoresist pattern having a width of the photoresist feature (D 1 );

d) forming a polysilazane coating over the photoresist pattern from a polysilazane coating composition, where the polysilazane coating is thicker than the photoresist pattern, and further where the polysilazane coating composition comprises a silicon/nitrogen polymer and an organic coating solvent;

e) etching the polysilazane coating to remove the polysilazane coating at least up to a level where the top of the photoresist pattern is revealed; and, f) dry etching to remove the photoresist and the underlayer which is beneath the photoresist, thereby forming an opening (D 1 ) beneath where the photoresist pattern was present,

further where the shrinkag%, {(D 1 -D 2 )/D 1 }*100, is in a range from about 5 to about 80.