My alarm gets louder over time so eventually you have to wake up or risk having the neighbors call the cops. Another option there are some phone apps that wake you at your lightest phase of sleep within a specific time window. So you lay the phone on the corner of the bed and I guess in lighter phases of sleep it can sense movements or something and will wake you up then even if it's a half hour early because if you wait it can be impossible and a bad feeling to wake up. It's supposed to help optimize your sleep cycle so you wake up feeling refreshed not groggy.