You need to get yourself some Terro ant poison. This stuff works like a charm and is great fun to use.

You put a quarter-sized blob of this stuff on some foil or wax paper and prod at an ant until he starts to drink it. He'll drink that yummy stuff until he's about twice his normal size. Afterwards, he goes back to the nest and tells all his buddies about the gourmet feast. After a couple of hours, you'll have a trail of hundreds of ants going to the blob. I usually put out a couple more blobs because there will be so many ants drinking at the first one that others can't join in.

No more ant problem.

Jim