What to put baby to sleep in?

My baby wakes immediately after laying him down. He's 7 weeks old. We've tried a Halo bassinet, crib, pack n play, bassinet on the pack n play, and rock n play. Nothing at all works. Currently I'm having to cosleep as that's the only way I can get any rest but that is not something I'm comfortable doing long term. Has anyone had this issue? Is there a sleeper or something out there that might help?