Not a new feature but Make players in their own fountain invincible?

I'm only talking about URF here When the game is coming to the end and the enemy team have 20 kills over our team, they all just camp right outside of fountain and constantly killing players right when they respawn. That's not only annoying and just plainly being an ass. I'm sure I'm not the only one that has to deal with this, but when the enemy team rather not end the game and get more kills right when players respawn is just annoying. Is it possible to make respawned players invincible until they use an ability, or something like that. So fed enemies don't camp right outside and spawn kill.