The manager first calls and explains the mission of the company and asks if you are interested, then you do an interview with the manager and R&D manager where they will try to get to know you as a person and what projects you worked on, then they will ask you some basic technical questions, mostly to see if you have critical thinking.
Interview questions [1]
Question 1
1) What projects did you work on and why did you choose this approach and not another approach