How can I get my sons dads rights taken away or get him for abandonment?

my sons dad left 5 month ago to go to florida we live in arizona he said if he couldn't bewith me he wanted nothing to do with my son. I am fine with that I just don't want to be able to come back into life later on in confuse him he has a dad in his life right now helping me with him. so my question is how can I get his rights taken away or get him for abandonment?