Self-Healing Transistors for Chip-Scale Starships
Working with the Korea Institute of Science and Technology (KAIST), NASA is pioneering the development of tiny spacecraft made from a single silicon chip that could slash interstellar exploration times.
On Wednesday at the International Electron Devices Meeting in San Francisco, NASA’s Dong-Il Moon will present new technology aimed at ensuring such spacecraft survive the intense radiation they’ll encounter on their journey.
If a silicon chip were used as a spacecraft, calculations suggest that it could travel at one-fifth of the speed of light and reach the nearest stars in just 20 years. That’s one hundred times faster than a conventional spacecraft can offer.
Twenty years in space is still too long for an ordinary silicon chip, because in addition to the frailties it suffers on earth, such as swings in temperature, it is bombarded by radiation of very high energy. This radiation leads to the accumulation of positively charged defects in the chip’s silicon dioxide layer, where they degrade device performance. The most serious of the impairments is an increase in the current that leaks through a transistor when it is supposed to be turned off, according to Yang-Kyu Choi, leader of the team at KAIST, where the work was done. However, there are also other issues, such as a shift in the voltage at which the transistor turns on.