Friday, January 16, 2009

US Patent 7477441 - Nanowire array anti-stiction layer for MEMS

US Patent 7,477,441

Stiction is a critical problem to many micromachining devices that ultimately limits the ability to miniaturize mechanical structures via lithography. Some conventional solutions include chemical coatings having anti-sticking surfaces and the use of mechanical standoffs providing spacing. This patent from Hewlett-Packard teaches another alternative based on the use of nanowire arrays as standoffs which may facilitate the further miniaturization of micromachines. Claim 1 reads:

1. A MEMS device, comprising:

a first member having a first surface;

a second member having a second surface, said first and second surfaces being separated by a gap that is closable by a MEMS actuation force applied to at least one of said first and second members; and

a standoff layer disposed on said first surface of said first member, said standoff layer providing standoff between said first and second surfaces upon a closing of said gap by said MEMS actuation force;

wherein said standoff layer comprises a plurality of nanowires anchored to said first surface and extending outward therefrom.