| While it’s similar to the kinds of biological damage that radiation can cause, because the radiation induced damage in DNA does work similarly, the energy from a radiation “hit” breaks bonds in the DNA molecule and causes knock on effects just like in the silicon crystal structures and metalic wires… The better biological analogy for the slow degradation of the integrated circuits due to radiation exposure would probably be heavy metal poisoning because the damage doesn’t typically spread or multiply like DNA damage and/or cancer does. Heavy metal poisoning “accumulates” it’s a slow buildup of something not meant to be there, which causes increasing problems with biological systems, until something is s disrupted by the heavy metal concentration giving a progression of symptoms until enough has built up and you get fatal symptoms. Edit: Simple example/comparison Everyone can (and we sadly have plenty of evidence for this) tolerate a fair bit of lead with an LD50 of 4500 to 5500 mg/kg or and a little bit of mercury with various mercury salts having an LD50 from 6-200 mg/kg, (LD50 is the abbreviation for "lethal dose, 50%", The LD50 for a substance is the dose required to kill half the members of a population.). Two heavy metals, two different levels of "exposure risks". Similarly the metal & doped semiconductors of an integrated circuit have have different sensitives to different kinds of radiation damage. Metal interconnects will tolerate radiation differently than the silicon which is different again to the insulation substrate... A Heavy ion, like a stray iron nucleus, (https://en.wikipedia.org/wiki/HZE_ion) is going to just dump a lot of energy and screw up a chunk of the atoms in the area around of whatever and wherever it hits, its like the mercury salts, you cant take a lot of hits like that, and fortunately they are statistically rare. Higher energy protons, like cosmic ray protons, can cause proton induced transmutation which will slowly turn the atoms you want into the atoms you don't want, and can cause the silicon transistors themselves to change similar to how we can (and sometimes do) use neutrons to dope semiconductors in the first place (https://en.wikipedia.org/wiki/Doping_(semiconductor)#Neutron...) Lower energy protons, and high energy electrons and positrons, can also lead to a slow buildup of electrical charges which can cause dielectric breakdowns and other unwanted effects, which can depending on what is involved and how it happens the cause of intermittent or permanent effects. Three different kinds of radiation, three different exposure disks. They are each like different "poisons", and the total exposure, the total absorbed dose of each of them accumulates over time... until one or more of them cause something critical to happen and render the hardware inoperable. |