ISBLANK/TODAY question to have the date, when populated, stay the same the following day

Hey everyone!

I am currently trying to create an excel spreadsheet for processing employees. I currently am using the formula

=IF(ISBLANK(D30),"",(TODAY()))

So anytime I input an employee's name, the date will automatically populate in the "Date Processed" category. The only problem I run into is because it is TODAY that I am using, every new day the date updates. What am I missing here in order to accomplish the date staying with the date I entered the employees name? Is there a way to do this? I am currently stumped. Thanks!

Paul