Two one-hour phone screenings, both were technical. First they told me about Corning's products and operations. It will be good if you read about their products before hand. Questions were related to basics of process controls; specifically, about model predictive control and PID control. More questions about multivariate analysis, like PCA, PLS, etc.
Was flown in for an on-site interview after that. The format consisted of a one-hour presentation on my PhD thesis, followed by 8 one-on-one interviews of one-hour each. Half of the interviews were technical, others were personality assessment interviews. I had to prepare for 3 weeks. You have to prepare well if you want to ace this interview. The people in general were very nice and easy-going. I enjoyed my conversations with them. Got to meet the whole team. Overall, a nice experience.