Extract IC binary can be separated into several different methods, they are include invasive microcontroller unlocking method, which has the highest cost and spending; non-invasive IC breaking method which is the cheapest method to extract IC binary, the final step also the most prevail method is semi-invasive mcu cracking method.

Ultra-violet radiation extract is a very useful way, and in order to prevent this method, all of the microcontroller IC which base upon the EEPROM will design a metal layer which can’t penetrate the ultra-violet radiation to cover the security fuse. For example, most of the 14 bits and 16 bits core PIC microcontroller has possessed this design.

It can not only protect the security fuse to be reset, and also make it very difficult to locate it security fuse through which can prevent IC code extraction effectively by ultra-violet radiation. Until recently, the faulty injection has been introduced, nowadays, there are two ways to extract IC against this protection, one of them is by using laser cutting or Focus Ion Beam, remove the top metal protective layer through reverse engineering technique.

Another way is increase the top metal layer, and use inverse memorizer unit which makes the ultra-violet radiation become more slow. For instance, AT89C51 microcontroller IC from ATMEL, its protection mechanism will make it security fuse can’t be reset once the wipe out operation proceed. However, if ultra-violet radiation can swift the security fuse from unsecure status to secure status, this characteristic can be used to locate the security fuse. In order to avoid this point, some of the microcontroller IC can use dual inverse security fuse and top metal layer protection, for example, PIC16F628 and PIC16F876 from MICROCHIP.