Soaking through diapers and wetting the bed (6 month old)

My baby sleeps on his belly and every single night he wakes up crying because he's soaked through his diaper and clothes and wet the bed. I've tried Huggies little snugglers, pampers swaddlers, and pampers baby dry which are supposed to last 12 hours and be specifically for overnight. I know sleeping on his belly is what's causing the leakage problem but I can't change that. Does anyone know of a diaper that works in this situation? I'm finally close to him sleeping through the night but we're having to wake up to change him each night and it's messing with him.