Use a high-power microscope and FIB to operate the chip to decrypt
In the chip decryption industry, the most correct decryption method is to adopt the method of hardware decryption, that is, use a specific fat-melting solution to dissolve the chip and expose the chip. When operating this step, certain skills are also required. Of course, When operating this step, sometimes the chip may be dissolved, that is, the wire is dissolved and broken, so that the chip will not be used at all. Of course, if the customer only has one mother chip, then it can be taken away. The binding factory will re-bind, but in this case, a certain fee will be incurred, and the time will be greatly lengthened. Generally, it will take a week to bind once. If the binding test fails, then it will be bound again. Surely, if this is the case, the technicians will open another chip and try to extract the program in the shortest possible time.
When the wafer is exposed, then we need to use a high-power microscope and FIB (focused ion beam equipment), use these two devices to find the encrypted position of the chip, and change the encrypted chip to unencrypted by changing its circuit. A state of the chip, and then use the programmer to read out the program inside the chip.
chip processing
1. The chip is opened by chemical method or special packaging type, and the gold wire is processed to take out the die.
2. Layer removal Remove layers by etching, including removal of protective layer polyimide, oxide layer, passivation layer, metal layer, etc.
3. Chip dyeing It is easy to identify through dyeing, mainly including highlighting of metal layers, dyeing of different types of well areas, and dyeing of ROM code points.
4. Photographing the chip The chip was photographed by an electron microscope (SEM).
5. Image stitching: Stitching the captured area images (software stitching, manual stitching after photo development).
6. Circuit analysis It can extract the digital circuit and analog circuit in the chip, organize it into an easy-to-understand hierarchical circuit diagram, and release it to customers in the form of written reports and electronic data.
