How to unlock AAA games?

To unlock the research for AAA games, you have to develop a Large size game with a score of 10-10-10-10 or 9-10-10-10 (source).

You complete this research in the R&D lab, which requires a design specialist. You can reduce the monetary cost of research by having multiple design specialists. When you start to develop a AAA title, the research option "Marketing Campaign" is temporarily unlocked in the R&D Lab, and it will generate hype (source).

If you also have a Hardware lab and are developing a AAA game, you can research hardware specific to your AAA title, which will increase either hype or sales. This acts similar to the Marketing Campaign from the R&D Lab (I can't remember or find a source).

Both the Hardware and R&D research boosts for AAA games cost 1000 research points.

You need to train one of the employees (It can be the creator) to be a design specialist. When they finish the training the option to build the R&D lab is opened.

In the R&D lab, you can research the AAA game, also you can research "Hardware" which opens the option to build your Hardware lab, where a new Console can be created.

According to the wiki, Hardware research is available as soon as the R&D lab is created, the AAA however needs some criteria to be met for it to available for research.