Semiconductor device fabrication and dry develop process suitable for critical dimension tunability and profile control
The critical dimension (CD) of features formed during the fabrication of a semiconductor device may be controlled through the use of a dry develop chemistry comprising O 2 , SO 2 and a hydrogen halide. For example, a dry develop chemistry comprising a gas comprising O 2 and a gas comprising SO 2 and a gas comprising HBr may be used to remove exposed areas of a carbon-based mask. The addition of HBr to the conventional O 2 and SO 2 dry develop chemistry enables a user to tune the critical dimension by growing, trimming and/or sloping the sidewalls and to enhance sidewall passivation and reduce sidewall bowing.
1. A method of fabricating a semiconductor device comprising:
forming a mask comprising carbon over a semiconductor device structure;
forming a preliminary mask comprising photoresist over at least a portion of the mask; and
exposing surfaces of the mask comprising carbon exposed through the preliminary mask comprising photoresist to a dry develop etch chemistry comprising O 2 , SO 2 , and at least one hydrogen halide to remove at least a portion of the mask comprising carbon and form at least one feature in the mask comprising carbon; and
adjusting a ratio of the at least one hydrogen halide to the O 2 in the dry develop etch chemistry during exposure of the surfaces of the mask comprising carbon to control a critical dimension of the at least one feature in the mask comprising carbon.
2. The method of claim 1 , wherein adjusting a ratio of the at least one hydrogen halide to the O 2 in the dry develop etch chemistry during exposure of the surfaces of the mask comprising carbon comprises adjusting at least one of a flow rate of the at least one hydrogen halide and a flow rate of the O 2 .
3. The method of claim 1 , wherein forming a preliminary mask comprising photoresist comprises forming a photomask over at least one antireflective coating.
4. The method of claim 3 , wherein forming a photomask over at least one antireflective coating comprises forming the photomask over at least one of an organic bottom antireflective coating (BARC) and an inorganic dielectric antireflective coating (DARC).
5. The method of claim 1 , wherein adjusting a ratio of the at least one hydrogen halide to the O 2 in the dry develop etch chemistry during exposure of the surfaces of the mask comprising carbon comprises controlling a relative flow rate of each of a gas comprising the O 2 , a gas comprising the SO 2 , and a passivating gas consisting of the at least one hydrogen halide to tune the critical dimension of the at least one feature in the mask comprising carbon during the removal of material from the mask comprising carbon.
6. The method of claim 1 , wherein exposing surfaces of the mask comprising carbon exposed through the preliminary mask comprising photoresist to a dry develop etch chemistry comprising O 2 , SO 2 , and at least one hydrogen halide comprises exposing surfaces of the mask comprising carbon exposed through the preliminary mask comprising photoresist to a dry develop etch chemistry comprising O 2 , SO 2 , and HBr.
7. The method of claim 1 , wherein exposing surfaces of the mask comprising carbon exposed through the preliminary mask comprising photoresist to a dry develop etch chemistry comprising O 2 , SO 2 , and at least one hydrogen halide comprises introducing a gas comprising the O 2 into a chamber at a flow rate of from about 10 sccm to about 30 sccm, introducing a gas comprising the SO 2 into the chamber at a flow rate of from about 30 sccm to about 50 sccm, and introducing HBr into the chamber at a flow rate of from about 25 sccm to about 75 sccm.
8. A method of forming an opening in a mask comprising:
forming a mask comprising carbon;
forming a preliminary mask comprising photoresist over the mask comprising carbon;
exposing at least one area of the mask comprising carbon exposed through the preliminary mask comprising photoresist to a gaseous reactive species derived from O 2 and SO 2 to form at least one opening in the mask comprising carbon;
exposing the at least one opening formed in the mask comprising carbon to a gaseous passivating species derived from HBr to form a passivation material comprising CBr 4 on at least one surface of the at least one opening; and
adjusting a concentration of the gaseous passivating species with respect to the gaseous reactive species during exposure of the at least one opening formed in the mask comprising carbon to control a critical dimension of the at least one opening.
9. The method of claim 8 , wherein exposing at least one area of the mask comprising carbon exposed through the preliminary mask comprising photoresist to a gaseous reactive species derived from O 2 and SO 2 to form at least one opening in the mask comprising carbon comprises exposing the at least one area of the mask comprising carbon exposed through the preliminary mask comprising photoresist to the gaseous reactive species derived from the O 2 and the SO 2 to form at least one opening having a width of less than or equal to about 120 nanometers.
10. The method of claim 8 , wherein exposing the at least one opening formed in the mask comprising carbon to a gaseous passivating species derived from HBr comprises forming the passivation material comprising the CBr 4 on surfaces of sidewalls of the at least one opening.
11. The method of claim 8 , wherein forming a mask comprising carbon comprises forming a mask comprising carbon having a thickness of between 1000 angstroms and 7000 angstroms.
12. A method of tuning at least one critical dimension of a feature of a mask comprising:
forming a mask comprising carbon over a semiconductor device structure;
forming a preliminary mask over the mask;
exposing at least one area of the mask comprising carbon exposed through the preliminary mask to a dry etch chemistry comprising O 2 , SO 2 , and a hydrogen halide to remove material from the mask comprising carbon to form at least one feature in the mask comprising carbon; and
changing a concentration of the hydrogen halide in the dry etch chemistry during exposure of the at least one area of the mask comprising carbon to tune a critical dimension of the at least one feature in the mask comprising carbon.
13. The method of claim 12 , wherein exposing at least one area of the mask comprising carbon exposed through the preliminary mask to a dry etch chemistry comprising O 2 , SO 2 , and a hydrogen halide comprises introducing a gas comprising the O 2 , a gas comprising the SO 2 , and a gas comprising HBr into a chamber, each of the gas comprising the O 2 and the gas comprising the SO 2 introduced at a flow rate less than a flow rate of the gas comprising the HBr.
14. The method of claim 12 , wherein exposing at least one area of the mask comprising carbon exposed through the preliminary mask to a dry etch chemistry comprising O 2 , SO 2 , and a hydrogen halide comprises introducing a gas comprising the O 2 into a chamber at from about 10 sccm to about 30 sccm, introducing a gas comprising the SO 2 into the chamber at about 30 sccm to about 50 sccm, and introducing a passivating gas consisting of the at least one hydrogen halide into the chamber at about 25 sccm to about 75 sccm.
15. The method of claim 12 , wherein changing a concentration of the hydrogen halide in the dry etch chemistry during exposure of the at least one area of the mask comprising carbon comprises adjusting a rate at which material is removed from the mask comprising carbon.
16. A method of fabricating a semiconductor device comprising:
forming a mask comprising carbon over a semiconductor device structure;
forming a negative mask over the mask comprising carbon;
forming a photomask over the negative mask;
removing at least one area of the negative mask exposed through the photomask;
forming a spacer mask over the mask;
removing at least one area of the negative mask exposed through the spacer mask;
exposing at least one area of the mask comprising carbon exposed through the spacer mask to a gaseous reactive species derived from O 2 and SO 2 to remove material from the mask comprising carbon to form a recess therein;
exposing the recess formed at the at least one area of the mask comprising carbon to a gaseous passivating species derived from at least one hydrogen halide to form a passivation material on a surface of the recess; and
adjusting a ratio of the gaseous passivating species derived from the at least one hydrogen halide to the gaseous reactive species derived from O 2 and SO 2 during exposure of the recess formed at the at least one area of the mask comprising carbon to control a critical dimension of the recess in the mask comprising carbon.
17. The method of claim 16 , wherein forming a negative mask over the mask comprising carbon comprises forming a negative mask comprising at least one of amorphous carbon and transparent carbon over a hard mask overlying the mask comprising carbon.
18. The method of claim 16 , wherein removing at least one area of the negative mask exposed through the photomask comprises exposing the at least one area of the negative mask to the gaseous reactive species derived from at least the O 2 and the SO 2 to form an opening therein and exposing the opening formed at the at least one area of the negative mask to the gaseous passivating species to form the passivation material on a surface of the opening.
19. The method of claim 18 , wherein exposing the opening formed at the at least one area of the negative mask to the gaseous passivating species to form the passivation material on a surface of the opening comprises exposing the opening formed at the at least one area of the negative mask to a gaseous passivating species derived from HBr to form a passivation material consisting of CBr 4 on sidewalls of the opening.
20. The method of claim 16 , wherein adjusting a ratio of the gaseous passivating species derived from the at least one hydrogen halide to the gaseous reactive species derived from O 2 and SO 2 during exposure of the recess formed at the at least one area of the mask comprising carbon to control a critical dimension of the recess in the mask comprising carbon comprises controlling a flow rate of a gaseous passivating gas consisting of HBr to tune the critical dimension of the recess in the mask comprising carbon during the removal of material from the mask comprising carbon.
21. The method of claim 20 , wherein:
exposing at least one area of the mask comprising carbon exposed through the spacer mask to a gaseous reactive species derived from O 2 and SO 2 comprises introducing a gas comprising the O 2 into a chamber at a flow rate of from about 10 sccm to about 30 sccm and introducing a gas comprising the SO 2 into the chamber at a flow rate of from about 30 sccm to about 50 sccm; and
exposing the recess formed at the at least one area of the mask comprising carbon to a gaseous passivating species derived from at least one hydrogen halide comprises introducing a gas consisting of the least one hydrogen halide into the chamber at a flow rate of from about 25 sccm to about 75 sccm.
22. The method of claim 16 , wherein exposing the recess formed at the at least one area of the mask comprising carbon to a gaseous passivating species derived from at least one hydrogen halide comprises exposing the recess formed at the at least one area of the mask comprising carbon to a gaseous passivating species derived from a passivating gas consisting of HBr.
23. The method of claim 22 , wherein exposing the recess formed at the at least one area of the mask comprising carbon to a gaseous passivating species derived from a passivating gas consisting of HBr comprises controlling a flow rate of the passivating gas to tune the critical dimension of the recess formed at the at least one area of the mask comprising carbon during the removal of material from the mask comprising carbon.
24. The method of claim 23 , wherein:
exposing the at least one area of the mask comprising carbon exposed through the spacer mask to a gaseous reactive species derived from O 2 and SO 2 comprises introducing a gas comprising the O 2 into a chamber at a flow rate of from about 10 sccm to about 30 sccm and introducing a gas comprising the SO 2 at a flow rate of from about 30 sccm to about 50 sccm; and
controlling a flow rate of the passivating gas comprises introducing the passivating gas into the chamber at a flow rate of from about 25 sccm to about 75 sccm.
25. The method of claim 16 , wherein forming a photomask over the negative mask comprises forming the photomask over an antireflective coating overlying the negative mask.
26. A method of fabricating a semiconductor device comprising:
forming a mask comprising carbon over a semiconductor device structure;
forming a preliminary mask comprising an oxide, polysilicon, and oxide hard mask over the mask comprising carbon;
forming a photomask over the preliminary mask;
removing at least one area of the preliminary mask exposed through the photomask;
exposing at least one area of the mask comprising carbon exposed through the preliminary mask to a dry etch chemistry comprising O 2 , SO 2 , and a hydrogen halide to remove at least a portion of the mask comprising carbon, forming at least one feature in the mask comprising carbon; and
adjusting a concentration of the hydrogen halide in the dry etch chemistry during exposure of the at least one area of the mask comprising carbon to control a critical dimension of the at least one feature in the mask comprising carbon.
27. The method of claim 26 , wherein exposing at least one area of the mask comprising carbon exposed through the preliminary mask to a dry etch chemistry comprising O 2 , SO 2 , and a hydrogen halide comprises exposing the at least one area of the mask comprising carbon exposed through the preliminary mask to a dry etch chemistry comprising O 2 , SO 2 , and HBr.
28. The method of claim 27 , wherein adjusting a concentration of the hydrogen halide in the dry etch chemistry during exposure of the at least one area of the mask comprising carbon to control a critical dimension of the at least one feature in the mask comprising carbon comprises controlling a flow rate of a passivating gas consisting of HBr to tune the critical dimension of the at least one feature in the mask comprising carbon during the removal of material from the mask comprising carbon.
29. The method of claim 28 , wherein controlling a flow rate of a passivating gas comprises introducing the passivating gas into a chamber at a flow rate of from about 25 sccm to about 75 sccm.