Don’t dismiss low stiction diamond drives

Scientists at the US government’s Sandia National Laboratory have created what they claim are the world’s first diamond micromachines.

The 1mm squared devices, etched from a surface of amorphous diamond, consist of 2 combs facing each other with interlaced teeth. One comb is bolted down and the other moves within the confines of a spring. A diamond rod is connected to the moveable comb drive and, as an electrical voltage to the comb cycles from positive to negative, the two sets of teeth repel and attract each other.

Silicon has been the element of choice for micromachines and amorphous diamond, despite its high strength, has only recently become practical because of a process developed at Sandia that eliminates the problem created by its internal stresses.

Diamond is also biocompatible and, compared to Silicon, exhibits low stiction. This is because Diamond is not hydrophilic, and therefore doesn’t attract water.

Sandia’s researchers estimate that these laboratory devices will be commercially marketable within 5 years.