Semiconductor device and method

1. A method of forming a semiconductor device, the method comprising:

forming a mask layer over a substrate;

forming an opening in the mask layer, the opening extending into the substrate;

depositing a gap-filling material in the opening, the gap-filling material filling the opening, a bottom portion of the gap-filling material extending below a top surface of the substrate;

performing a plasma treatment on the gap-filling material;

forming a film material over the gap-filling material, the film material having a high etch selectivity with the gap-filling material, a lowest point of the film material being above a top surface of the mask layer;

removing the film material, a portion of the gap-filling material over the mask layer, and the mask layer; and

patterning the substrate using the remaining portion of the gap-filling material as a mask.

2. The method of claim 1 , wherein the gap-filling material has an indentation that is centered above the opening.

3. The method of claim 1 , wherein the gap-filling material comprises SiO x , SiC x O y , SiN, TiO, Al 2 O 3 , or TiN.

4. The method of claim 1 , wherein depositing the gap-filling material comprises an atomic layer deposition (ALD) process comprising a precursor chosen from the group consisting of tris(dimethylamino)silane (3DMAS), bis(tertiary-butyl-amino) silane (BTBAS), bis(diethylamino)silane (BDEAS), trimethylaluminum (TMA, Al(CH 3 ) 6 ), diethylzinc (DEZ), tetrakis(dimethylamino)titanium (TDMAT), titanium isopropoxide (TTIP), TiCl 4 , tetrakis(dimethylamido)zirconium (Zr(NMe 2 ) 4 ), zirconium tetrachloride (ZrCl 4 ), and tetrakis-dimethyl-amine tin (TDMASn).

5. The method of claim 4 , wherein the ALD process further comprises a reaction gas chosen from the group consisting of Ar, O 2 , O 3 , H 2 O 2 , CO 2 , and N 2 O.

6. The method of claim 4 , wherein the ALD process is performed at a temperature below 300° C.

7. The method of claim 4 further comprising performing multiple cycles of the ALD process and performing the plasma treatment between cycles of the ALD process.

8. The method of claim 7 , wherein the plasma treatment comprises a duration in a range of 0.1 seconds to 20 seconds.

9. The method of claim 7 , wherein the plasma treatment comprises a plasma power in a range of 50 W to 1000 W and a bias power in a range of 0 W to 500 W.

10. The method of claim 7 , wherein the plasma treatment is performed at a temperature in a range of 50° C. to 260° C.

11. A method of forming a semiconductor device, the method comprising:

depositing a top mask layer on a hard mask, the hard mask being on a substrate;

patterning an opening in the top mask layer;

forming a first film material over the top mask layer, the first film material filling the opening;

performing a plasma treatment on the first film material;

forming a second film material over the first film material, the second film material having a high etch selectivity with the first film material;

removing the second film material, a portion of the first film material over the top mask layer, and the top mask layer; and

patterning the hard mask using the remaining portion of the first film material as a mask.

12. The method of claim 11 , wherein the first film material and the second film material are chosen from the group consisting of SiO x , SiC x O y , SiN, TiO, Al 2 O 3 , and TiN.

13. The method of claim 11 , wherein the second film material is formed with a thickness in a range of 10 nm to 40 nm.

14. The method of claim 11 , wherein forming the first film material forms a first indentation in the first film material centered over the opening.

15. The method of claim 14 , wherein forming the second film material forms a second indentation in the second film material centered over the first indentation.

16. A method for manufacturing an integrated circuit, the method comprising:

forming a first layer over a semiconductor substrate;

depositing a hard mask on the first layer;

forming a photomask layer over the hard mask;

patterning a plurality of openings in the photomask layer;

performing a deposition cycle of a first film material, the deposition cycle comprising:

depositing the first film material over the photomask layer, the first film material filling the plurality of openings; and

performing a plasma treatment on the first film material;

removing the photomask layer, the removing the photomask layer also removing a portion of the first film material over the photomask layer;

patterning the hard mask using the remaining portion of the first film material as a mask; and

patterning the first layer using the patterned hard mask as a mask.

17. The method of claim 16 further comprising:

forming a second film material over the first film material, the second film material having a high etch selectivity with the first film material; and

removing the second film material.

18. The method of claim 17 , wherein the removing the second film material is performed while removing the photomask layer.

19. The method of claim 17 further comprising the removing the photomask layer also removing a portion of the second film material and the patterning the hard mask also using the remaining portion of the second film material as a mask.

20. The method of claim 19 , wherein the patterning the hard mask further comprises removing the remaining portion of the second film material.