first answer: If you own a necronomican then no you could bring them back to "life" if you would call it that. If you do not then yes in fact they are dead and not living and will never "wake" up and...
Semen, the fluid that carries sperm out of the body, is not alive. The sperm are the tiny swimmers in the semen that can cause pregnancy, and they are indeed alive for awhile out side the man's body.