In the sci-fi I've read/listened to with audiobooks, none have mentioned a god. I've listened to an alien race that creates starships by expanding a single atom so it's nearly indestructible (Puppeteers from Larry Niven's Ringworld), to transporting whole planets across the galaxy (also Ringworld), to creating the Halo (Halo) to preserve life (inspiration probably gotten from Ringworld). Are the authors atheist or satanists, I have no idea.