Read IC Firmware is a complicate process through which we can extract the embedded firmware from encrypted IC. So one of the most effective ways is use laser light to change the status of transistor and read the IC firmware.
And there is one more thing which is quite necessary to pay attention is the relationship between the photocurrent and laser wavelength. Since the IC reading can cause almost all of the concentration of photons on the surface and the decrease of parasitic photons on the substrage. Through calculate the relationship between laser wavelength and current of power supply from reversor, IC reader will find that the short wavelength could be more efficiency when read IC firmware or software. The shorter the wavelength, the current difference between status 0 and 1 could be bigger. And through the experiment on the IC reading also approves this point. As the experiment can tell, laser with 650 nanometers can recognize the different status of current from power supply of reversor. But if use the laser with 805 nanometers wavelength, its difference could be almost close to the noise level. The main source when read IC software is from photocurrent of substrage, and wavelength reduction can also cut down its effect on the IC reading. And once again the result of stimulation confirm the application of focus ion beam can help to read out the status of IC reversor. Meanwhile, it also helps to clarify that it is necessary to choose the proper laser with right wavelength when read out IC content.
