6 week old won't sleep unless held - is this normal?

My son is 6 weeks old and will only sleep if I'm holding him or my wife is holding him. The second we put him down in the bassinet he wakes up screaming. We're getting maybe 2-3 hours of actual sleep a night between us. Is this a phase? Will he outgrow it? We're both running on fumes here and I'm genuinely worried about my wife's mental health. She's been crying a lot. Should we try the Snoo or is that a waste of money?