Rough surface could keep small electronic parts from sticking together

March 5, 2014

When a piece of gift-wrapping tape sticks to itself, it's frustrating, but when small parts in a microgear or micromotor stick together, an electronic device may not work well, if at all. Scientists now report in the journal ACS Applied Materials & Interfaces that rough zinc oxide coatings can prevent tiny silicon parts from adhering to each other. The study could accelerate the development of even more advanced, high-performance electronics and small sensors.

Xinchun Lu and colleagues explain that adhesion is a big concern when designing very small silicon-based machines called microelectromechanical systems (MEMS). Today, MEMS are in many consumer products, such as cell phones, tablets, car airbags and inkjet printers. On this large scale, manufacturers can make sure that small parts have enough space and don't touch. However, when moving to smaller devices and parts for high-performance electronics, space is at a premium, and it's more likely that parts will touch. Silicon is widely used in MEMS devices, but it is sticky. The typical solution is to coat silicon with a water-repellent coating. Roughening up a surface can also help minimize contact between surfaces. Lu's group set out to see whether combining the two—using a water-repellent zinc oxide film with a rough surface—could work.

They investigated the stickiness of various films in the laboratory. They found that thicker films were rougher and had a lower adhesion force (were less sticky) than thin ones. Low humidity also helped, say the researchers.

Explore further: Next-generation device enabling improved smartphone battery life and high definition in televisions

Related Stories

Microtechnology: Double-layer capping solves two problems

January 15, 2014

Continual downsizing of technology means that researchers have to develop ever more ingenious methods of packaging and protecting their tiny devices. Jae-Wung Lee and co-workers at the A*STAR Institute of Microelectronics, ...

Recommended for you

Electrical circuit made of gel can repair itself

August 25, 2015

(Phys.org)—Scientists have fabricated a flexible electrical circuit that, when cut into two pieces, can repair itself and fully restore its original conductivity. The circuit is made of a new gel that possesses a combination ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.