Restore Chip Program is a complicate technology and data romance can be one of the main technologies. The general process of data remanence is through keeping the security key inside the processor in the state of static RAM, the component will power off to set up and component being manipulated, and the content inside the RAM will get lost, which can protect the security key from being stolen.

As we all know once the temperature around the chip is below minus 20 degree, the content inside the RAM will be frozen. Lots of the chips will defined the terms as a restoring temperature whenever the surround temperature below this point. We have done some related experiments about the connection and relations among the security key and data keeping capability inside modern chip with the temperature outside.

Our experiment has proved that the traditional thoughts about the IC program restoring technique is no more effective. Even in the high temperature, the data remanence is still a problem even in the high temperature. The data remanence has effect not only on the SRAM, but also the DRAM, UV EPROM, EEPROM and flash.

As a result of that, the remaining information can still be obtained from the already erased chip which will bring a lot of security issue with the facility which is much shorter than the normal impulse or power supply noise (the swift wave vibration in the power supply voltage) will affect the transistors inside chip and will contribute directly to lead other one or several triggers into the wrong instructions, sometimes even can’t be supported by microcode. Although we can’t foresee what kind of noise will probably cause which mistake, but it can proceed the systematic search simply in the process of restore chip program.