How does radiation damage and break electronics?

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I tried to read the Wikipedia article on radiation hardening electronics, but I couldn’t understand it when it tried to explain how radiation effects electronics. So explain like I’m 5, how does radiation effect electronics?

Bonus question, how does radiation hardening work?

In: Physics

Electronic, or really the ics, are built of really tiny physical structures, transistors mainly.

Radiation are tiny tiny particles that go really really fast and they pass through almost anything, except when they don’t.

When a radiation particle hits a transistor it gets destroyed.

Radiation hardening is done by shielding, e.g bigger case, or on chip level by encasing the chips in material that absorb these particles.

Or by selecting the technology that is less suceptible by radiation damage.

Redundancy, by adding more chips or chips with built in redundancy

Generally hardening is done on several levels of a device, eg special case, backup chips, purpose built ic’s etc etc

Electronics is a wide casting term for many kinds of devices and components that operate on the principles of electrity, the flow of electrons

Radiation is a wide casting term for anything that radiates energy from a source.

Some kinds of radiation, particularly ones like high energy ionizing radiation, will cause changes in the way that materials behave in relation to electricity. If a electrical component is supposed to behave one way and radiation changes it to behave in some other way, then obviously the electronic machine is broken. If your machine is supposed to sense a light and make a beep, but radiation changes it from making a beep to making a honk, then your light beeper machine is broken

The mechanism that this happens varies by what kind of radiation and what kind of electrical component. Your kitchen microwave is a machine that emits microwave radiation. You work it by putting a cup of water inside, hitting start, and the machine emits microwave radiation to heat up your cup of water. Let’s say you instead put a light bulb inside. The microwave radiation will interact with the materials in the light bulb instead. It will have several kinds of effects on the light bulb. In the end, it may or may not break the light bulb by changing the way the materials in the light bulb interact with electricity.

Hardening is the change of design of a component to try to counter the effects of radiation on your component. Depending on what kind of radiation and what your component is supsiptible to, there will be different ways of hardening, such as shielding with materials, increasing the size of wires, different ways of laying down the wires

Most electronics these days have semiconductor devices in them like transistors. The semiconductor that is most commonly used is the element silicon, and the atoms are organized in a crystal lattice, like when you line up marbles in rows and columns. This silicon is usually doped, meaning that every few atoms, it has an atom of something other than silicon, like boron or phosphorus but more on that later. The atoms in the lattice are held in place by their valence electrons.

Radiation, which is high energy photons, can “collide” with one of those electrons and knock it out of place, causing the atom also get knocked out of place. In this way, a defect can form in the lattice.

The dopant phosphorus has one more electron than is needed in bonding, and the dopant boron has one less. The extra electron that the phosphorus has is callef a “free electron” because it can easily move around the lattice without causing damage to it. This happens a photon of visible light, particularly green light, “collides” with it and knocks it in to a higher energy state. This is like knocking a planet or moon out of orbit. The boron has one less electron than silicon so provides a spot for the free electron to move in to. This is how solar panels work.

Transistors are more complex but rely on electrons being in certain regions at certain operating points to function properly.

When the lattice in semiconductor devices becomes damaged by defects, the free electrons cannot move in the intended way or to the intended region and the device fail to work properly.