Electrowetting at a liquid metal-semiconductor junction
Abstract
We report electrowetting at a liquid metal-semiconductor (Schottky) junction using of a mercury droplet resting on silicon. This is demonstrated using n-type and p-type single-crystal silicon wafers of different doping levels. The voltage-dependent wetting contact angle variation of the mercury droplet is observed to depend on both the underlying semiconductor doping density and type. The electrowetting behavior can be explained by the voltage-dependent modulation of the capacitance of a Schottky junction; current-voltage and capacitance-voltage measurements indicate this to be the case. A modified Young-Lippmann electrowetting equation—formulated using a well-established metal-semiconductor junction model—agrees well with the observations.
- Publication:
-
Applied Physics Letters
- Pub Date:
- August 2013
- DOI:
- Bibcode:
- 2013ApPhL.103g4104A
- Keywords:
-
- capacitance;
- contact angle;
- drops;
- elemental semiconductors;
- liquid metals;
- mercury (metal);
- Schottky barriers;
- semiconductor doping;
- semiconductor-metal boundaries;
- silicon;
- wetting;
- 73.40.Ns;
- 81.05.Cy;
- 68.03.Cd;
- 73.30.+y;
- Metal-nonmetal contacts;
- Elemental semiconductors;
- Surface tension and related phenomena;
- Surface double layers Schottky barriers and work functions