Method of fabricating integrated circuit devices

1. A method of fabricating an integrated circuit device, the method comprising:

forming, on a substrate, a developable bottom anti-reflective coating (DBARC) layer comprising a chemically amplified polymer;

forming, on the DBARC layer, a photoresist layer comprising a non-chemically amplified resin, a photoactive compound (PAC), and a photoacid generator (PAG);

generating a first acid from the PAG and a second acid derived from the PAC in a first region of the photoresist layer by exposing the first region of the photoresist layer to light;

diffusing the first acid in the exposed first region of the photoresist layer into a first DBARC region of the DBARC layer, the first DBARC region facing the first region of the photoresist layer; and

removing the first region and the first DBARC region by developing the photoresist layer and the DBARC layer simultaneously,

wherein the first acid has a first acid dissociation constant (pKa) of about −20 to about 1, and the second acid has a second pKa of about 1 to about 10.

2. The method according to claim 1 , wherein the forming of the DBARC layer comprises:

coating, on the substrate, a DBARC composition comprising the chemically amplified polymer, a crosslinking agent, and a solvent; and

thermally treating the coated DBARC composition.

3. The method according to claim 2 , wherein the DBARC composition further comprises at least one of a thermal acid generator (TAG), a surfactant, and a base.

4. The method according to claim 1 , wherein, in the forming of the DBARC layer, the chemically amplified polymer comprises a repeating unit comprising an acrylate derivative that includes an acid-labile group.

5. The method according to claim 1 , wherein the forming of the DBARC layer comprises coating, on the substrate, a DBARC composition not comprising a PAG.

6. The method according to claim 1 , wherein, in the forming of the photoresist layer, the non-chemically amplified resin does not comprise an acid-labile group.

7. The method according to claim 1 , wherein the forming of the photoresist layer comprises:

coating, on the substrate, a photoresist composition comprising an alkali-soluble novolac resin, a PAC, and the PAG; and

thermally treating the coated photoresist composition.

8. The method according to claim 7 ,

wherein the PAC comprises a naphthoquinonediazide compound, and

wherein the PAG comprises a diazodisulfone compound or an onium salt.

9. The method according to claim 1 , wherein the generating of the first acid from the PAG comprises exposing the first region by using an i-line (365 nm) light source.

10. The method according to claim 1 , wherein the DBARC layer does not comprise a material generating an acid by light.

11. A method of fabricating an integrated circuit device, the method comprising:

forming, on a layer-to-be-processed, a developable bottom anti-reflective coating (DBARC) layer comprising a chemically amplified polymer and a crosslinking agent;

forming, on the DBARC layer, a photoresist layer comprising a non-chemically amplified resin, a photoactive compound (PAC), and a photoacid generator (PAG);

generating a first acid derived from the PAG and a second acid derived from the PAC in a first region of the photoresist layer by exposing the first region of the photoresist layer to light;

diffusing the first acid in the exposed first region of the photoresist layer into a first DBARC region of the DBARC layer;

forming an opening that exposes the layer-to-be-processed by developing the photoresist layer and the DBARC layer simultaneously so as to remove the first region and the first DBARC region; and

processing the layer-to-be-processed through the opening,

wherein the first acid has a first acid dissociation constant (pKa) of about −20 to about 1, and the second acid has a second pKa of about 1 to about 10.

12. The method according to claim 11 ,

wherein the chemically amplified polymer of the DBARC layer comprises a repeating unit comprising an acrylate derivative that contains an acid-labile group, and

wherein the non-chemically amplified resin of the photoresist layer does not comprise an acid-labile group.

13. The method according to claim 11 , wherein, in the forming of the photoresist layer, the non-chemically amplified resin comprises an alkali-soluble novolac resin, the PAC comprises a naphthoquinonediazide compound, and the PAG comprises a diazodisulfone compound or an onium salt.

14. The method according to claim 11 , wherein, in the forming of the photoresist layer, the PAG comprises a diazodisulfone compound represented by the following formula:

wherein each of R 5 and R 6 is a C1 to C16 linear or branched alkyl group, a C6 to C20 cycloalkyl group having monocyclic or polycyclic ring, or a C6 to C20 aryl group.

15. The method according to claim 11 , wherein, in the exposing of the first region, the first acid comprises sulfonic acid.

16. The method according to claim 11 , wherein, in the forming of the opening, a total surface area of an exposed top surface of the layer-to-be-processed exposed by the opening is at least 50% of a total surface area of the entire top surface of the layer-to-be-processed.

17. The method according to claim 11 , wherein the processing of the layer-to-be-processed comprises implanting impurity ions into the layer-to-be-processed through the opening.

18. A method of fabricating an integrated circuit device, the method comprising:

forming, on a substrate, a developable bottom anti-reflective coating (DBARC) layer comprising a chemically amplified polymer and a crosslinking agent;

forming, on the DBARC layer, a photoresist layer comprising an alkali-soluble novolac resin, a photoacid generator (PAG), and a photoactive compound (PAC), the PAG comprising at least one of a diazodisulfone compound and a sulfonate;

generating sulfonic acid from the PAG and an acid from the PAC in a first region of the photoresist layer by exposing the first region of the photoresist layer to light;

diffusing the sulfonic acid in the first region into a first DBARC region of the DBARC layer; and

removing the first region and the first DBARC region by developing the photoresist layer and the DBARC layer,

wherein the acid from the PAC has a pKa of about 1 to about 10.

19. The method according to claim 18 , wherein the forming of the DBARC layer comprises:

coating a DBARC composition on the substrate, wherein the DBARC composition comprises a polymer, the crosslinking agent, and a solvent and does not comprise a PAG, and the polymer comprises a repeating unit that comprises an acrylate derivative containing an acid-labile group; and

thermally treating the coated DBARC composition.

20. The method according to claim 18 , wherein the diazodisulfone compound is represented by the following formula:

wherein each of R 5 and R 6 is a C1 to C16 linear or branched alkyl group, a C6 to C20 cycloalkyl group having monocyclic or polycyclic ring, or a C6 to C20 aryl group.