Polarity-dependent electro-wetting or -dewetting on a conductive silicon substrate

TL;DR

This paper demonstrates a method for manipulating droplets on a conductive silicon substrate using low-voltage electric signals to induce wetting or dewetting, enabling precise control without additional layers.

Contribution

The study introduces a polarity-dependent electro-wetting technique on a conductive silicon surface that operates at low voltages with ionic surfactants, without extra layers.

Findings

Contact angle changes exceed 15° or -20° with ±3 V voltage.

Droplet manipulation achieved on a hydrophilic conductive substrate.

Electro-wetting controlled solely by electric signals and ionic surfactants.

Abstract

We demonstrate droplet manipulation using electric signals to induce the liquid to wet or dewet on a hydrophilic conductive substrate in the air without adding layers. In this phenomenon, the contact angle changes more than 15{\deg} or -20{\deg} by using the ionic surfactant mediated droplets, with only \pm3 volts of the actuation voltage.