Siten0308 - Tuesday, January 9, 2018 8:28 AM
Unasked questions are the stupid ones.
But no it won't use tempdb. If you are wanting to understand more details of the process, check the following articles:
Understanding SQL Server Backups
And this is a good reference when you start searching on it and reading different posts, articles:
A SQL Server DBA myth a day: (30/30) backup myths
Sue