editor's blog
Subscribe Now

A Diving Board, Water Drop, and Flashlight

Two gentlemen at the Institut d’Electronique, de Microélectronique et de Nanotechnologie (IEMN) at the University of Lille in France, have demonstrating an interesting proof of concept of a new mechanical switching mechanism that relies on the interplay between mechanical and capillary forces as well as how “wet” a drop can get.

The concept is based upon the fact that the wetting properties of a droplet – that is, how easily it spreads out on a surface – can be changed capacitively. Placing a drop on a thin insulator with a semiconductor region below it, and touching the drop above with a conductor, makes the droplet part of a capacitor. The droplet becomes one plate, the semiconductor – p-type in their experiment – is the other plate. Modulating the voltage to which the p-region is biased changes the wetting properties of the droplet, making it sink down or rise up as the bias is modulated. This is “electrowetting.”

Now, by shining plain-old white light on the semiconductor – nothing fancy, no “lasers” – you further modulate the charge in the semiconductor, further affecting the wetting. Presumably this only works with a transparent insulating layer. This is referred to as “photoelectrowetting.” Gesundheit.

Here’s how you make a switch, then. You take a MEMS cantilever and place the droplet right under the tip (or close enough to have some leverage). The cantilever is a spring and wants to stay straight. But once in contact with the droplet, the capillary force makes it “stick” to the surface of the drop. So when the droplet rises or falls, then the cantilever rises and falls with it – as long as the restoring spring force doesn’t overcome the capillary force and break the connection.

Putting it all together, the idea is that, in principle, given this setup, you should be able to use the cantilever as a relay (some portion of it being able to contact another conductor), using white light to activate the switch. The good news is that, because the switching mechanism is capacitive, it makes an extremely low-power switching mechanism (as they point out, it’s like the gate of an MOS transistor, qualitatively).

You can find their complete paper here.

Leave a Reply

featured blogs
Sep 21, 2023
Wireless communication in workplace wearables protects and boosts the occupational safety and productivity of industrial workers and front-line teams....
Sep 21, 2023
Labforge is a Waterloo, Ontario-based company that designs, builds, and manufactures smart cameras used in industrial automation and defense applications. By bringing artificial intelligence (AI) into their vision systems with Cadence , they can automate tasks that are diffic...
Sep 21, 2023
At Qualcomm AI Research, we are working on applications of generative modelling to embodied AI and robotics, in order to enable more capabilities in robotics....
Sep 21, 2023
Not knowing all the stuff I don't know didn't come easy. I've had to read a lot of books to get where I am....
Sep 21, 2023
See how we're accelerating the multi-die system chip design flow with partner Samsung Foundry, making it easier to meet PPA and time-to-market goals.The post Samsung Foundry and Synopsys Accelerate Multi-Die System Design appeared first on Chip Design....

featured video

TDK PowerHap Piezo Actuators for Ideal Haptic Feedback

Sponsored by TDK

The PowerHap product line features high acceleration and large forces in a very compact design, coupled with a short response time. TDK’s piezo actuators also offers good sensing functionality by using the inverse piezo effect. Typical applications for the include automotive displays, smartphones and tablet.

Click here for more information about PowerHap Piezo Actuators

featured paper

Intel's Chiplet Leadership Delivers Industry-Leading Capabilities at an Accelerated Pace

Sponsored by Intel

We're proud of our long history of rapid innovation in #FPGA development. With the help of Intel's Embedded Multi-Die Interconnect Bridge (EMIB), we’ve been able to advance our FPGAs at breakneck speed. In this blog, Intel’s Deepali Trehan charts the incredible history of our chiplet technology advancement from 2011 to today, and the many advantages of Intel's programmable logic devices, including the flexibility to combine a variety of IP from different process nodes and foundries, quicker time-to-market for new technologies and the ability to build higher-capacity semiconductors

To learn more about chiplet architecture in Intel FPGA devices visit: https://intel.ly/47JKL5h

featured chalk talk

NXP GoldVIP: Integration Platform for Intelligent Connected Vehicles
Today’s intelligent connected vehicle designs are smarter and safer than ever before and this has a lot to do with a rapidly increasing technological convergence of sensors, machine learning, over the air updates, in-vehicle high bandwidth networking and more. In this episode of Chalk Talk, Amelia Dalton chats with Brian Carlson from NXP about NXP’s new GoldVIP Platform. They examine the benefits that this kind of software integration platform can bring to automotive designs and how you can take a test drive of the GoldVIP for yourself.
Nov 29, 2022
35,992 views