Radiation resistant MEMS could survive nuclear attack

MEMS devices could be used for computer and robotics circuitry to withstand radiation in a damaged nuclear power plant or deep space, even keep infrastructure working in a nuclear attack.

According to researchers at the University of Utah, MEMS developed logic gate devices have been developed which can survive intense ionizing radiation that would fry most circuitry.

Robots have already been used in areas of extreme radiation, such as the nuclear power plants which were severely damaged as a result of the tsunami in Japan last year. But despite heavy shielding it is only a matter of time before essential electronics cease to work.

The team at Utah claims to have developed MEMS which could create circuits able to withstand such conditions.

Tradional silicon semiconductors rely on channels to carry electrical current.  However radiation creates its own current and this can disrupt the ability of the semiconducting material to perform.

MEMS, on the other hand, do not have a semiconducting channel, and instead function by electrical charges causing electrodes to touch each other, acting like a switch. This means that they are not as susceptible to the effects of radiation.

There are downsides to MEMS, with silicon electronics around a thousand times quicker and substantially smaller.  MEMS devices also require larger voltages to switch from one state to another.

However, the team has worked to reduce the number of devices need to create a computer, and have also succeeded in reducing by a factor of 10 the amount of voltage needed to switch.

The next steps for the team, which has been funded by the Defense Advanced Research Projects Agency (DARPA), is to start to create small computers based on the simplified MEMS circuits.

According to the researchers the end result could mean that the circuits, which survived 277 degree heat and two hours in the Utah university research reactor, will be able to withstand “cosmic ionizing radiation”, or to “help robotics to control troubled nuclear reactors without degradation”.