[paulgerhardt]

That unreplicability between chips is actually a very, very desirable property when fingerprinting chips (sometimes known as ChipDNA) to implement unique keys for each chip. You use precisely this property (plus a lot of magic to control for temperature as you point out) to give each chip its own physically unclonable key. This has wonderfully interesting properties.

[rowanG077]

The technical term is usually "Physical unclonable function".