I don't think there's such major called quality engineering or SPC in US universities. However, IMO, if you are more specified in statistical analysis part, you could try statistics departments; if you are more of process control and/or management, you could try industrial engineering departments. I can't recommend universities for you I'm afraid. But you can Google US university ranks within a specific subject. Go through their website and locate appropriate departments. There should be links like "People" or "Staff" which present a list of professors. You could check out what they are studying on. You could even go further and email those professors who impress you for questions, etc. Go for those professors whose work match and interest you the most. Good luck!