Engineers at Stanford’s ‘XLab’ are working on tiny electronic devices that could withstand some of the most extreme conditions imaginable.
The research group, which specialises in developing microsystems for extreme environments, hopes to study the most remote and inhospitable regions both here on Earth and in space.
Reaching temperatures of up to 480 degrees Celsius (more than 890 Fahrenheit) and doused with sulfuric acid rains, the atmosphere surrounding Venus is just the place they mean. With the metallic components in silicon-based semiconductors melting at around 300oC (572oF), today’s electronics wouldn’t stand a chance.
Atomic scale heat shields
When it comes to developing heat, corrosion and radiation resistant electronics, the team have decided to think small. Really small.
Using nano-scale slices of material, XLab’s principle investigator, Debbie Senesky, and her team have been devising heat shields as thin as a single atom. Ateeq Suria, a graduate student in mechanical engineering, has been working with Senesky to break the temperature barrier. Their solution comes in the form of an ultra-thin coating that can be applied to electronic devices, protecting them from temperatures of up to 600oC (over 1000oF).
“The diameter of human hair is about 70 micrometres,” said Suria. “These coatings are about a hundredth of that width.”
Pushing their research further, the team hope to protect devices from temperatures of around 900oC, far hotter than they are ever likely to get in space. While they may not be exposed to such extreme heat, these tests can rapidly age the materials, providing key understanding of how long they could survive.
Resisting radiation in space
In addition to surviving the trials of Venus’ atmosphere, the team need to make sure their devices can make the journey. Outside of the Earth’s protective atmosphere, spacecraft and satellites are bombarded by radiation that degrades materials.
Initial work suggests that XLab’s protected sensors could survive up to 50 years of radiation while in the Earth’s orbit. If the team’s manufacturing processes to produce these resistant nano-materials prove effective, a collaboration with NASA could even be on the horizon. If materials can be made cheaply, efficiently and consistently to a high quality, the technology could be applied to design the next generations of probes and landers being launched into space.
Before sending their devices beyond Earth’s pull, an essential part of the teams experimenting is the rigorous series of tests all materials must be put through.
Deep within NASA’s Glenn Research Centre in Cleveland, Ohio, the conditions on Venus have been replicated. The ‘Venus simulator’ mimics the pressure, chemistry and temperatures found on the second planet from the sun, making it the ideal test site for electronics being sent into space.
To mirror the effects of space radiation, devices are taken to a similar facility at either the Los Alamos National Laboratory or NASA’s Ames Research Centre.
Senesky hopes that by studying Venus we can better understand our own world. Nobody knows for sure how Venus became so hot, but scientists suggest a runaway greenhouse effect billions of years ago could have caused the planet to suck in heat, creating its current scorching atmosphere.
“If we can understand the history of Venus, maybe we can understand and positively impact the future evolution of our own habitat,” said Senesky.
Understanding the effects of space travel on electronic devices could also prove invaluable here on Earth. The study, according to researchers, was initially fuelled by the temperatures recorded inside car engines. Reaching over 1000oC (1832oF), this environment is just too hot for current electrics to function accurately. In order to monitor and optimise engine performance, sensors must instead be placed further away and out of danger, introducing error into measurements. By applying the space-age technology, sensors could be placed inside the engine, delivering much more accurate results.
Further applications for these tough devices could see them deployed to oil and gas wellbores, geothermal vents, and even on the inside of aircraft engines and gas turbines.