Why are processors usually made to have max temperature of 100 C? Why not more or less?

I have looked online but found nothing relating to my question. To clarify, I'm absolutely not asking how to lower temperatures or anything about performance.

I am saying, what is the reason for it being 100 C and not 200 C for instance? Is there a component in the CPU that has a lower melting point and as such the whole thing has been limited to prevent it from getting burnt?

What influenced this decision?

*If my question is still not clear let me know in the comments.