Methods and systems of material removal and pattern transfer
View Patent ↗Polymerized material on a substrate may be removed by exposure to vacuum ultraviolet (VUV) radiation from an energy source within a gaseous atmosphere of a controlled composition. Following such removal, additional etching techniques are also described for nano-imprinting.
1. A method for removing solidified polymerizable material on a substrate, comprising the steps of:
(a) forming a patterned layer, said patterned layer having pattern features and a residual layer on a at least portion of the substrate;
(b) providing a vacuum ultraviolet (VUV) radiation source;
(c) positioning said substrate such that said portion of said substrate having a residual layer is in alignment with said vacuum ultraviolet (VUV) radiation source; and
(d) providing a gas composition of less than 10% oxygen between said portion of said substrate and said vacuum ultraviolet (VUV) radiation source;
(e) irradiating said substrate while in the presence of said gas composition with vacuum ultraviolet (VUV) radiation to remove said residual layer from said portion of said substrate while preserving said patterned features.
2. The method of claim 1 wherein said provided vacuum ultraviolet (VUV) radiation source is enclosed within a chamber, said chamber having an exposure aperture, and wherein said substrate positioning step further comprises positioning said substrate portion in alignment with said exposure aperture.
3. The method of claim 2 further comprising providing said gas composition to said chamber.
4. The method of claim 1 wherein said vacuum ultraviolet (VUV) radiation is provided at a wavelength of between 140 to 190 nm.
5. The method of claim 1 wherein said vacuum ultraviolet (VUV) radiation is provided at a peak intensity of approximately 172 nm and a spectral bandwidth of approximately 15 nm FWHM.
6. The method of claim 1 wherein said provided gas composition contains less than 5% oxygen.
7. A method for transferring a pattern on a hard mask layer or a substrate, comprising the steps of:
(a) forming a hard mask on a substrate;
(b) forming a patterned layer, said patterned layer having pattern features and a residual layer on a at least a portion of said hard mask;
(c) providing a vacuum ultraviolet (VUV) radiation source;
(d) positioning said substrate such that said portion of said hard mask having a residual layer is in alignment with said vacuum ultraviolet (VUV) radiation source;
(e) providing an gas composition of less than 10% oxygen between said portion of said hard mask and said vacuum ultraviolet (VUV) radiation source;
(f) irradiating said substrate while in the presence of said gas composition with vacuum ultraviolet (VUV) radiation to remove said residual layer from said portion of said hard mask while preserving said pattern features; and
(e) transferring said pattern to said hard mask using a batch process step to remove portions of said hard mask.
8. The method of claim 7 wherein said provided vacuum ultraviolet (VUV) radiation source is enclosed within a chamber, said chamber having an exposure aperture, and wherein said substrate positioning step further comprises positioning said hard mask portion in alignment with said exposure aperture.
9. The method of claim 8 further comprising providing said gas composition to said chamber.
10. The method of claim 7 wherein said vacuum ultraviolet (VUV) radiation is provided at a wavelength of between 140 to 190 nm.
11. The method of claim 7 wherein said vacuum ultraviolet (VUV) radiation is provided at a peak intensity of approximately 172 nm and a spectral bandwidth of approximately 15 nm FWHM.
12. The method of claim 7 wherein said provided inert gas composition contains less than 5% oxygen.
13. The method of claim 7 wherein said batch process step uses hydrofluoric acid.
14. The method of claim 7 further comprising the step of removing the patterned layer.
15. The method of claim 14 further comprising transferring said pattern to said substrate by using a batch process step to remove portions of said substrate.
16. The method of claim 15 wherein the batch process step selectively etches the substrate.
17. The method of claim 16 wherein the substrate is silicon, the hard mask is silicon oxide, and potassium hydroxide is used in the batch processing step.
18. A method for removing solidified polymerizable material on a substrate, comprising the steps of:
(a) forming a patterned layer, said patterned layer having pattern features and a residual layer on a at least portion of the substrate;
(b) providing a vacuum ultraviolet (VUV) radiation source;
(c) positioning said substrate such that said portion of said substrate having a residual layer is in alignment with said vacuum ultraviolet (VUV) radiation source; and
(d) providing a nitrogen-enriched environment of less than 2% oxygen between said portion of said substrate and said vacuum ultraviolet (VUV) radiation source;
(e) irradiating said substrate while in the presence of said nitrogen-enriched environment with vacuum ultraviolet (VUV) radiation to remove said residual layer from said portion of said substrate while preserving said pattern features.
19. The method of claim 18 wherein said provided vacuum ultraviolet (VUV) radiation source is enclosed within a chamber, said chamber having an exposure aperture, and wherein said substrate positioning step further comprises positioning said substrate portion in alignment with said exposure aperture.
20. The method of claim 19 further Comprising providing said nitrogen-enriched environment to said chamber.
21. The method of claim 18 wherein said vacuum ultraviolet (VUV) radiation is provided at a wavelength of between 140 to 190 nm.
22. The method of claim 18 wherein said vacuum ultraviolet (VUV) radiation is provided at a peak intensity of approximately 172 nm and a spectral bandwidth of approximately 15 nm FWHM.