That would take a FIB (Focused Ion Beam) workstation. Very expensive. Christopher Tarnovsky has one and has used it to hack a bunch of TPM chips and smart cards

That would take a FIB (Focused Ion Beam) workstation. Very expensive. Christopher Tarnovsky has one and has used it to hack a bunch of TPM chips and smart cards. It's very impressive, especially since some of what he does is done while the chip is powered on... Delidding isn't brain surgery. Removing and bypassing (depositing new metal to form wires / cutting old connections with the ion beam) a mesh, then probing and decrypting the data bus is much closer. And even then, if you mess up you grab a new chip, with brain surgery you can't just get another patient. As someone who's had brain surgery, I'm very, very glad brain surgeons don't often mess up!