Some hobbyists use these die shots to reverse engineer older chips, bypassing the need to decap the chips themselves. The craft is explained nicely in this vide

Some hobbyists use these die shots to reverse engineer older chips, bypassing the need to decap the chips themselves. The craft is explained nicely in this video https://www.youtube.com/watch?v=aHx-XUA6f9g https://www.youtube.com/watch?v=aHx-XUA6f9g.