The maven-deploy-plugin allows you to configure the deploy phase to deploy to a server using scp. There is a page in the documentation that describes how it can be done.
I believe this will replace the normal deployment instead of add to it, so it may not be what you’re after.
If you need to deploy to a traditional Maven repository as well as deliver the file to the remote server, you will need to use the scp task as the other answers suggest.
In this answer I’ve described how to configure the ftp task, the scp task is almost identical except you may need to add the keyfile and passphrase attributes (and change the task name from ftp to scp obviously).