Temperature based attacks ( Heat Faulting)

The idea behind heat faulting is to apply a high temperature for a long amount of time until the machine starts faulting. These faults can disclose un-encrypted information that will help the attacker. The idea is to increase the temperature until right before the machine breaks and hold it there. As it slowly breaks down the machine will leak information that you need.
This may sounds strange to some but heat has a large effect on electronics. Some changes can happen both reversible and irreversible that effect the way the chip works:

1) Johnson-Nyquist Noise or thermal noise is electronic noise  that is brought about by heat agitating charger carriers is increased. This noise interferes with bits coming into and going out of the chip causing commands to be misread causing random operation and faults.

2) A dopant is used to create a characteristic in a semiconductor. These become mobile at high heat and can fry semiconductors which also cause faults.

3) Read only memory can leak charge at a high enough temperature which causes memory corruption and contributes to more faults.
Though all of this may sound very scary and make you want to hide your computer it is ok to relax. Heat based side channel attacks have only been used successfully in lab environments for the time being and require very specific temperature ranges and specialty equipment.