Understanding the long-term effects of Total Ionizing Dose (TID) on semiconductor reliability is crucial for developing future electronics capable of operating in extreme environments, enhancing overall mission success in space exploration.
NASA's $5.2 billion Europa Clipper mission launched on October 14, 2023 is designed to explore Jupiter's moon Europa and check if it has the potential to support life. However, the mission faces a tough challenge due to the harsh space environment around Jupiter. Jupiter has a very strong magnetic field that creates powerful radiation belts, which blast any spacecraft passing through with high-energy particles. These particles can be dangerous to the electronics on the spacecraft, especially the semiconductor transistors. Kim Horner reports that scientists were concerned about whether the transistors would keep working properly during the mission’s long journey.
Dr. Robert Baumann, an expert in how radiation affects electronics, explains that these high-energy particles can cause a problem called ionization in the transistors. This leads to a buildup of extra charge in the insulating layers, which can gradually affect the way transistors work. This issue, known as Total Ionizing Dose (TID), can eventually cause the transistors to stop working correctly. They could get stuck in either an "on" or "off" state, similar to a water tap that won’t stop flowing or won’t turn on at all, causing the electronics to malfunction.
To solve this problem, NASA tested the transistors thoroughly. The good news is that the transistors onboard the Europa Clipper can handle the radiation, thanks to a process called annealing, which helps them recover. The spacecraft spends only one day out of 21 in the most intense radiation areas around Jupiter. During the rest of the time, the transistors get a chance to repair themselves from any damage. Kim Horner highlights that this mission showcases the importance of new technology in semiconductors, especially for surviving the extreme conditions of space.