If you want the share to be a LUN, here's your steps:
1. Create a new volume and a LUN (16TB is your LUN size limit)
2. Map the LUN to the server
3. Copy the data from CIFS to the LUN - there's no way to convert to a LUN in place.
Keep in mind that if you do this, only that server gets fast, local-ish access to the LUN. Everyone else that accesses the data will need to use the Windows server as the connection point; you can't map a LUN to multiple hosts. That Windows server would need to act as an SMB server to that LUN.
If you're looking for faster scanning of the share, I'd suggest using something like XCP and NFS to scan.
And if you can, leverage file analytics to get near instant access to file info.
Also, the next release of ONTAP will have some on-box tools for this as well.