TIL "MOSFET"

Via the New York Times, this fascinating story about chips that can withstand high amounts of radiation on the upcoming NASA Europa Clipper mission: 

People at NASA headquarters take deep breaths when the words “First Story” appear in their email. Late this spring, Curt Niebur, the lead scientist for flight programs, received such a message.

“You open that email right away,” Dr. Niebur said. “You read it, and then you reply, ‘Thank you for sharing,’ and then you bury your face in a pillow and you howl in terror.”

The matter prompting Dr. Niebur’s apprehension involved Europa Clipper, one of NASA’s most scientifically important missions. The agency’s science division created the “First Story” process to encourage science project staff members to communicate potentially bad news without fear of overreaction by leadership.

This news seemed exceptionally bad. If what Dr. Niebur was reading was true, Europa Clipper was cooked.

The story is the radiation-resistant chips known as MOSFETs, and how NASA dealt with the discovery that the chips did not work as well as thought without grounding the mission. For manufacturing nerds like me, it takes another article to learn that the German manufacturer of the chips is being mum about what the problem is: 

On May 3, engineers at NASA’s Jet Propulsion Laboratory, in Pasadena, Calif., the primary manufacturer of the spacecraft, learned from a “non-NASA customer”* that vital, radiation-resistant chips failed when tested at radiation levels “significantly lower” than they were supposed to. Jordan Evans, the Europa Clipper project manager at the lab, presented the problem last month at a meeting of the Space Studies Board, a committee of the National Academies of Science that advises NASA.

The flawed chips in Europa Clipper are called metal-oxide-semiconductor field-effect transistors, or MOSFETs.

“We’re seeing some of these MOSFETs fail at lower radiation levels” than the prevailing environment around Europa, Shannon Fitzpatrick, the head of flight programs for NASA’s Planetary Science Division, said during a meeting of the Planetary Science Advisory Committee, a group of outside researchers who advise NASA, this week. She also said in the meeting that engineers had not yet solved the issue.

The chips currently in Europa Clipper are manufactured by Infineon Technologies, a German semiconductor firm. They are also used in military spacecraft. An Infineon spokesperson declined to comment on “actual or potential customers,” but said that the company has “stringent processes in place to ensure compliance with all relevant quality and performance standards for our products.”

It can't be fun to be an Infineon engineer for the last few months. Curious what the issue was. 

*Amused to learn via Science that it was a classified non-NASA customer