I applied online, but not to the position for which I was interviewed. Received an e-mail several months later trying to set up a phone interview that never wound up getting setup (due to changes in the group leader positions). Received a phone call several months after that for a phone interview. That went well and I was told that I would hear more information in about 3 weeks. 22 days later I had a phone call and e-mail asking me for my availability for an onsite interview which took place 3 weeks later. The onsite consisted of a 30 minute meeting and then several 30minute 1 on 1 meetings with current and former senior members of the group. I then gave a 30-45 minute presentation on a technical subject. I was offered a job the following week.

First you start with a round of behavioral and get to know you questions. If selected to move on you will then have to give a technical presentation in which everyone from the department is invited and will grill you following your presentation. Overall a very standard process but hard to BS your way through it is you have no idea what you're talking about. Select a technical subject that you are able to defend and you will be fine.