This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision Next revision | Previous revision | ||
|
semi-invasive [2018/02/25 04:15] mcmaster |
semi-invasive [2019/12/08 14:23] (current) mcmaster |
||
|---|---|---|---|
| Line 1: | Line 1: | ||
| - | ====== Photonic (UV) EPROM erase ====== | + | ====== UV EPROM erase ====== |
| EPROM/EEPROM/flash can be erased by shining UV light or x-rays into the surrounding oxide. This slightly oxidizes it, letting the floating gate to drain out. | EPROM/EEPROM/flash can be erased by shining UV light or x-rays into the surrounding oxide. This slightly oxidizes it, letting the floating gate to drain out. | ||
| + | |||
| + | Usually a masking compound is applied to selectively block UV to the firmware, with red nail polish being the most popular or at least traditional. | ||
| + | |||
| + | {{:mcmaster:nail_polish:overview.jpg?400|}} | ||
| + | |||
| + | McMaster misc notes | ||
| + | |||
| + | Application | ||
| + | * Use a single hair brush | ||
| + | * Ex: cut down MG 855-5 horse hair brush | ||
| + | * Place chip in bowl | ||
| + | * Shallow fill bowl with acetone | ||
| + | * Creates shield gas to prevent nail polish drying out in small quantities | ||
| + | * Place paper towel on side to elevate gas enough to keep nail polish liquid | ||
| + | * If nail polish is too viscous, slightly set top of chip with IPA | ||
| + | * Apply a glob of nail polish, then use the spring force of the liquid to precisely move it around | ||
| + | * By gently agitating the liquid boundaries its possible to very precisely move it forward | ||
| + | * Place the nail polish in the bowl in some sort of holder | ||
| + | * Ex: above image has a 1/4-20 SHCS with a nut screwed on as a base | ||
| + | |||
| + | Nail polish | ||
| + | * [[https://www.amazon.com/gp/product/B00LT8S30G/|Revlon ColorStay Gel Envy Longwear Nail Enamel, Queen of Hearts]] | ||
| + | * Also can be used to look fabulous! | ||
| + | * Bought at local store a while back and it seems to work well enough | ||
| + | * Other colors probably fine, but red is easy to see | ||
| + | |||
| + | {{:mcmaster:nail_polish:pipette.jpg?400|}} | ||
| + | |||
| + | Above: fine polypropylene tip for more aggressive cleaning. The tool is strong enough to damage bond wires though, so use sparingly | ||
| + | |||
| + | Nail polish removal | ||
| + | * Bulk removal with acetone, but leaves some residue around edges | ||
| + | * Remaining residue softened with acetone | ||
| + | * Remove using single hair brush if possible | ||
| + | * Can be more aggressive with PP monofilament wire | ||
| + | * Cold H2SO4 also works well. Wash with IPA then acetone | ||
| + | * Washing with water may really heat up the mixture | ||
| + | |||
| ===== Angle ===== | ===== Angle ===== | ||
| Line 16: | Line 54: | ||
| - | ====== Non-invasive attacks ====== | + | ====== X-ray EPROM erase ====== |
| - | + | ||
| - | [[jtag|JTAG]] | + | |
| - | + | ||
| - | [[ripping|Ripping firmware]] | + | |
| - | [[dpa|Differential power analysis]] | + | TODO: add links to misc papers |