Will Radiation Damage My Electronic Component?
Well, yes and no…
Regarding radiation damage on electronic components, if you are looking for a simple “yes” or “no” answer, stop reading now. In fact, you may feel like we did not answer the question at all – and you would be correct. Some of the parameters we take into consideration when analyzing potential radiation damage to electronics include, the type of radiation, time of exposure, radiation flux, and fabrication technology of the electronic component itself.
The reality is, radiation is all around us: from concrete walls to cat litter to cosmic rays. To help you figure out this whole topic, let’s break down what ionizing radiation is. There are two types: electromagnetic waves and subatomic particles. Electromagnetic waves are x-rays and gamma rays, while subparticles can be protons, neutrons, electrons, pions, muons, and others.
You find subparticles at the place where I used to work, Fermi National Accelerator Laboratory. There we collided protons and antiprotons to create a soup of subparticles. Needless to say, our electronics were subjected to an immense amount of “bad” radiation for electronics. Particles are bad, but waves are not as bad, because they travel through components, where particles like to “stop” inside of components and cause lots of damage.
But first, let’s define “damage.” Bulk damage is when the energy transferred to the silicon atom is sufficient to remove it from the crystal lattice. This damage is permanent. However, most x-ray inspection systems simply don’t have enough energy to cause this type of damage.
Surface damage is when the passage of ionizing radiation in the silicon oxide on semiconductors can cause a buildup of trapped charge in the oxide layers and potentially alter microcode or configware resident on certain devices such as FPGA’s and memory circuits. This can cause “bit flips” in digital circuits, or voltage spikes in analog circuits. However, this is also permanent.
A single-event upset (SEU) is a change of state caused by one single ionizing particle striking a sensitive node in a microelectronic device, such as in a microprocessor, semiconductor memory, or power transistors. This damage mechanism is dynamic, as it happens when the device is powered up and operating. This is not permanent and can be fixed!
Back to our original question: will your x-ray machine damage the component? It is unlikely. You will not be operating the component during an inspection, so SEU is also not an issue. That leaves us with surface damage. Let’s see what we can do to minimize the chances of this damage mechanism. We cannot change the radiation type or energy, but we can minimize the radiation flux and exposure time. Taking these precautions help prevent components from unnecessary radiation. But consider this, from the time the component exits the manufacturer, the part will be x-rayed by the screening equipment at airports, border crossings, and ports of entry and shipping warehouses. Some of these organizations use very powerful x-ray machines.
So we come back to your simple question: will radiation damage my electronic component?
The best answer we can give you is: it depends.