Open new window in code_behind of a button _Click event

I have a web form where the user enters a new item into inventory.  They click the SUBMIT button where I call a BLL method to validate and push data to the DAL where it is inserted into SQL Server. 

On a successful insert, I want to open a new window containing the physical tag for printing.  The tag is printed and affixed to the new inventory item.  I want the tag in a new window because the data entry from is used over and over .  I don't want the user to hit a back button or navigate backwards to enter another item.

How can I open a new window in the code behind of the button _Click event?  I don't think injecting some javascript into the button with Attribute.Add is a good idea, since it will open the new window before the data is inserted into SQL.

Thanks
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