High-energy neutrons stream through our atmosphere. These neutrons can cause computer errors known as single-event upsets. Although these upsets do not result in permanent damage, they can crash computer applications, such as those vital to operating aircraft.
The rates of these single-event upsets drastically increase as you go higher into the atmosphere. For example, at 30,000 feet, the intensity and rate of these errors increase 300 fold compared to ground-level. Researchers have pondered how best to study these single-event upsets, given their propensity to occur higher into the atmosphere. Scientists at Fujitsu Labs took to the top of a volcano to conduct research on single-event upsets. The top of the Mauna Kea volcano is 4,200 meters above sea level. At 4,200 feet, the intensity and rate of these errors is 16 times higher than ground-level, giving researchers plenty to study.
Fujitsu researchers worked with engineers from the National Astronomical Observatory of Japan to measure both the rate of single-event upsets and intensity of neutrons. Researchers are interested in examining the relationship between intensity of neutrons and the rate of single-event upsets because little is known about the strength of that relationship. We currently know that, as the intensity of neutrons increases (e.g., in higher altitudes), the rate of single-event upsets also increases. However, there could be a one-to-one correspondence between intensity of neutrons increases and the rate of single-event upsets, or the relationship could be weaker, Indeed, exactly how tightly these two factors are related is unknown, prompting these researchers to study the relationship more closely. They took these measurements both inside and outside of Japan’s Subaru telescope, which sits at the top of Mauna Kea. Taking measurements both inside and outside of the telescope allowed the researchers to study the impact of radiation shielding, which is typically found to provide only minimal protection against the particles.
Single-event upsets used to be pretty rare events; however, semiconductor technology has advanced by leaps and bounds in the past couple of years. As engineers have been able to reduce the size of cells, chip designers have been able to raise the number of cells per chip. While this makes the chips more efficient, allowing for higher processing power, it also puts the chip at much greater risk for a single-event upset. Modern technology may be getting faster, but its also more likely to crash due to radiation.
To help prevent single-event upsets, chip designers can add mitigation (e.g., error correction codes). However, not only do few engineers have this skill set, but it is very costly and time consuming to do so, which ultimately results in increased prices. Lucid Circuit’s RSAP technology offers a more efficient solution to test technology for susceptibility to single-event upsets. Read more about RSAP on our website.