Semiconductor device and method of manufacture
Semiconductor devices and methods which utilize a treatment process of a bottom anti-reflective layer are provided. The treatment process may be a physical treatment process in which material is added in order to fill holes and pores within the material of the bottom anti-reflective layer or else the treatment process may be a chemical treatment process in which a chemical reaction is used to form a protective layer. By treating the bottom anti-reflective layer the diffusion of subsequently applied chemicals is reduced or eliminated, thereby helping to prevent defects that arise from such diffusion.
1. A method of manufacturing a semiconductor device, the method comprising:
forming a first gate layer over a raised semiconductor region;
forming a hard mask over the first gate layer;
applying a bottom anti-reflective layer over the hard mask, the bottom anti-reflective layer having a first diffusibility with respect to a first chemical, the bottom anti-reflective layer comprising a polymer with a chromophore group;
patterning the hard mask through the bottom anti-reflective layer;
after the patterning the hard mask, reducing the first diffusibility to a second diffusibility with respect to the first chemical, wherein the reducing the first diffusibility to the second diffusibility comprises applying either isopropyl alcohol or hexamethyldisilazane to the bottom anti-reflective layer; and
removing a portion of the first gate layer using the first chemical while the bottom anti-reflective layer is present.
2. The method of claim 1 , wherein the applying either isopropyl alcohol or hexamethyldisilazane applies isopropyl alcohol.
3. The method of claim 1 , wherein the applying either isopropyl alcohol or hexamethyldisilazane applies hexamethyldisilazane.
4. The method of claim 1 , wherein the applying either isopropyl alcohol or hexamethyldisilazane is performed at a temperature of between about 5° C. and about 25° C.
5. The method of claim 1 , wherein the applying either isopropyl alcohol or hexamethyldisilazane is performed for a time period between about 5 seconds and about 60 seconds.
6. The method of claim 1 , wherein the applying either isopropyl alcohol or hexamethyldisilazane reacts and forms a protective layer.
7. The method of claim 6 , wherein the protective layer has a thickness of between about 5 Å and 10 Å.
8. A method of manufacturing a semiconductor device, the method comprising:
forming a first gate layer over a raised semiconductor region;
applying a bottom anti-reflective layer over the first gate layer;
forming a self-aligned monolayer on a top surface and sidewall of the bottom anti-reflective layer; and
applying an etchant to the self-aligned monolayer and the first gate layer, wherein the etchant removes a portion of the first gate layer.
9. The method of claim 8 , wherein the forming the self-aligned monolayer comprises applying a first reactant to the top surface and sidewall of the bottom anti-reflective layer.
10. The method of claim 9 , wherein the first reactant comprises an organic molecule with an OH group.
11. The method of claim 9 , wherein the first reactant comprises an organic molecule with a carboxylic acid group.
12. The method of claim 8 , wherein the first gate layer is a first p-metal work function layer.
13. The method of claim 8 , wherein the first gate layer is a first hard mask layer.
14. The method of claim 8 , further comprising:
removing the anti-reflective layer; and
depositing a fill material.
15. A method of manufacturing a semiconductor device, the method comprising:
applying a first treatment chemical to a bottom anti-reflective layer, the first treatment chemical comprising either isopropyl alcohol or hexamethyldisilazane; and
after the applying the first treatment chemical, applying an etchant to the bottom anti-reflective layer and a first gate metal layer, the etchant removing an exposed portion of the first gate metal layer.
16. The method of claim 15 , wherein the first treatment chemical comprises isopropyl alcohol.
17. The method of claim 15 , wherein the first treatment chemical comprises hexamethyldisilazane.
18. The method of claim 15 , wherein the applying the first treatment chemical forms a protective layer along an outer surface of the bottom anti-reflective layer.
19. The method of claim 18 , wherein during the applying the first treatment chemical the first treatment chemical penetrates into the bottom anti-reflective layer a distance of between about 5 Å and about 100 Å.
20. The method of claim 19 , wherein during the applying the first treatment chemical the first treatment chemical penetrates into the bottom anti-reflective layer a distance of between about 5 Å and about 10 Å.