How to identify shorts on IC's
For that kind of package you should be able to see solder bridges with a jeweler's loupe.  A jeweler's loupe is essential equipment for doing any kind of soldering these days.

Another possibility is that the solder connections are fine but that the part is going into latchup when turned on.  This is particularly likely if any of the inputs are held above power, even for a brief time, during powerup.