Manufacturing of hard masks for patterning magnetic media
View Patent ↗Embodiments of the present invention relate to systems and methods for designing and manufacturing hard masks used in the creation of patterned magnetic media and, more particularly, patterned magnetic recording media used in hard disk drives (e.g., bit patterned media (BPM)). In some embodiments, the hard mask incorporates at least one layer of Ta (tantalum) and at least one layer of C (carbon) and is used during ion implantation of a pattern onto magnetic media. The hard mask can be fabricated with a high aspect ratio to achieve small feature sizes while maintaining its effectiveness as a mask, is robust enough to withstand the ion implantation process, and can be removed after the ion implantation process with minimal damage to the magnetic media.
1. A method for manufacturing a magnetic recording medium, the method comprising:
depositing a first carbon (C) layer over a magnetic layer of the magnetic recording medium;
depositing a first tantalum (Ta) layer over the first carbon layer;
depositing a second carbon (C) layer over the first tantalum layer;
depositing a second tantalum (Ta) layer over the second carbon layer;
depositing a photoresist layer over the second tantalum layer;
patterning the photoresist layer to form a photoresist patterned layer;
transferring the photoresist patterned layer into the second tantalum layer to form a tantalum patterned layer;
transferring the tantalum patterned layer into the second carbon layer to form a carbon patterned layer; and
performing an implantation process.
2. The method of claim 1 , wherein the first carbon layer has a first thickness and the second carbon layer has a second thickness that meets or exceeds the first thickness.
3. The method of claim 1 , wherein the first carbon layer has a thickness of approximately 2 nm.
4. The method of claim 1 , wherein the first tantalum layer has a thickness of approximately 1 nm.
5. The method of claim 1 , wherein the second carbon layer is etched such that etched features of the second carbon patterned layer have residual carbon layer remaining.
6. The method of claim 1 , further comprising removing the second tantalum layer and removing the second carbon layer.
7. The method of claim 6 , wherein removing the second tantalum layer comprises dry etching using a fluorine-based gas chemistry.
8. The method of claim 6 , wherein removing the second carbon layer comprises dry etching using an oxygen-based gas chemistry.
9. The method of claim 1 , further comprising removing the first tantalum layer and removing the first carbon layer.
10. The method of claim 9 , wherein removing the first tantalum layer comprises dry etching using a fluorine-based gas chemistry.
11. The method of claim 9 , wherein removing the first carbon layer comprises dry etching using a hydrogen-based gas chemistry.
12. The method of claim 1 , wherein transferring the tantalum patterned layer to the second carbon layer comprises dry etching using an oxygen-based gas chemistry.
13. The method of claim 1 , wherein transferring the photoresist patterned layer to the second tantalum layer comprises dry etching using a fluorine-based gas chemistry.
14. The method of claim 1 , wherein the second tantalum layer has a thickness sufficient to still cover the second carbon layer subsequent to the photoresist patterned layer being etched into the second tantalum layer.
15. The method of claim 1 , wherein the second tantalum layer has a thickness sufficient to protect the second carbon layer subsequent to the photoresist patterned layer being etched into the second tantalum layer.
16. The method of claim 1 , wherein the second tantalum layer has a thickness between approximately 1 nm and 2 nm.