Driving characteristics of the electrowetting-on-dielectric device using atomic-layer-deposited aluminum oxide as the dielectric

Jong Hyeon Chang, Dae Young Choi, Seungoh Han, James Jungho Pak

Research output: Contribution to journalArticle

55 Citations (Scopus)

Abstract

Electrowetting on dielectric (EWOD) is useful in manipulating droplets for digital (droplet-based) microfluidics, but its high driving voltage over several tens of volts has been a barrier to overcome. This article presents the characteristics of EWOD device with aluminum oxide (Al 2O 3, ε r ≈ 10) deposited by atomic layer deposition (ALD), for the first time as the high-k dielectric for lowering the EWOD driving voltage substantially. The EWOD device of the single-plate configuration was fabricated by several steps for the control electrode array of 1 mm × 1 mm squares with 50 μm space, the dielectric layer of 1,270 Å thick ALD Al 2O 3, the reference electrode of 20 μm wide line electrode, and the hydrophobic surface treatment by Teflon-AF coating, respectively. We observed the movement of a 2 μl water droplet in an air environment, applying a voltage between one of the control electrodes and the reference electrode in contact with the droplet. The droplet velocity exponentially depending on the applied voltage below 15 V was obtained. The measured threshold voltage to move the droplet was as low as 3 V which is the lowest voltage reported so far in the EWOD researches. This result opens a possibility of manipulating droplets, without any surfactant or oil treatment, at only a few volts by EWOD using ALD Al 2O 3 as the dielectric.

Original languageEnglish
Pages (from-to)269-273
Number of pages5
JournalMicrofluidics and Nanofluidics
Volume8
Issue number2
DOIs
Publication statusPublished - 2010 Feb 1

Fingerprint

Dielectric devices
Aluminum Oxide
aluminum oxides
Aluminum
Oxides
Atomic layer deposition
Electrodes
Electric potential
atomic layer epitaxy
electrodes
electric potential
Polytetrafluoroethylene
Threshold voltage
Polytetrafluoroethylenes
Microfluidics
Surface-Active Agents
Contacts (fluid mechanics)
Surface treatment
teflon (trademark)
Oils

Keywords

  • Aluminum oxide (Al O )
  • Atomic layer deposition (ALD)
  • Digital microfluidics
  • Electrowetting on dielectric (EWOD)
  • Single-plate configuration

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials
  • Materials Chemistry

Cite this

Driving characteristics of the electrowetting-on-dielectric device using atomic-layer-deposited aluminum oxide as the dielectric. / Chang, Jong Hyeon; Choi, Dae Young; Han, Seungoh; Pak, James Jungho.

In: Microfluidics and Nanofluidics, Vol. 8, No. 2, 01.02.2010, p. 269-273.

Research output: Contribution to journalArticle

@article{9d16bbe1bd59431a806ac1160661d501,
title = "Driving characteristics of the electrowetting-on-dielectric device using atomic-layer-deposited aluminum oxide as the dielectric",
abstract = "Electrowetting on dielectric (EWOD) is useful in manipulating droplets for digital (droplet-based) microfluidics, but its high driving voltage over several tens of volts has been a barrier to overcome. This article presents the characteristics of EWOD device with aluminum oxide (Al 2O 3, ε r ≈ 10) deposited by atomic layer deposition (ALD), for the first time as the high-k dielectric for lowering the EWOD driving voltage substantially. The EWOD device of the single-plate configuration was fabricated by several steps for the control electrode array of 1 mm × 1 mm squares with 50 μm space, the dielectric layer of 1,270 {\AA} thick ALD Al 2O 3, the reference electrode of 20 μm wide line electrode, and the hydrophobic surface treatment by Teflon-AF coating, respectively. We observed the movement of a 2 μl water droplet in an air environment, applying a voltage between one of the control electrodes and the reference electrode in contact with the droplet. The droplet velocity exponentially depending on the applied voltage below 15 V was obtained. The measured threshold voltage to move the droplet was as low as 3 V which is the lowest voltage reported so far in the EWOD researches. This result opens a possibility of manipulating droplets, without any surfactant or oil treatment, at only a few volts by EWOD using ALD Al 2O 3 as the dielectric.",
keywords = "Aluminum oxide (Al O ), Atomic layer deposition (ALD), Digital microfluidics, Electrowetting on dielectric (EWOD), Single-plate configuration",
author = "Chang, {Jong Hyeon} and Choi, {Dae Young} and Seungoh Han and Pak, {James Jungho}",
year = "2010",
month = "2",
day = "1",
doi = "10.1007/s10404-009-0511-9",
language = "English",
volume = "8",
pages = "269--273",
journal = "Microfluidics and Nanofluidics",
issn = "1613-4982",
publisher = "Springer Verlag",
number = "2",

}

TY - JOUR

T1 - Driving characteristics of the electrowetting-on-dielectric device using atomic-layer-deposited aluminum oxide as the dielectric

AU - Chang, Jong Hyeon

AU - Choi, Dae Young

AU - Han, Seungoh

AU - Pak, James Jungho

PY - 2010/2/1

Y1 - 2010/2/1

N2 - Electrowetting on dielectric (EWOD) is useful in manipulating droplets for digital (droplet-based) microfluidics, but its high driving voltage over several tens of volts has been a barrier to overcome. This article presents the characteristics of EWOD device with aluminum oxide (Al 2O 3, ε r ≈ 10) deposited by atomic layer deposition (ALD), for the first time as the high-k dielectric for lowering the EWOD driving voltage substantially. The EWOD device of the single-plate configuration was fabricated by several steps for the control electrode array of 1 mm × 1 mm squares with 50 μm space, the dielectric layer of 1,270 Å thick ALD Al 2O 3, the reference electrode of 20 μm wide line electrode, and the hydrophobic surface treatment by Teflon-AF coating, respectively. We observed the movement of a 2 μl water droplet in an air environment, applying a voltage between one of the control electrodes and the reference electrode in contact with the droplet. The droplet velocity exponentially depending on the applied voltage below 15 V was obtained. The measured threshold voltage to move the droplet was as low as 3 V which is the lowest voltage reported so far in the EWOD researches. This result opens a possibility of manipulating droplets, without any surfactant or oil treatment, at only a few volts by EWOD using ALD Al 2O 3 as the dielectric.

AB - Electrowetting on dielectric (EWOD) is useful in manipulating droplets for digital (droplet-based) microfluidics, but its high driving voltage over several tens of volts has been a barrier to overcome. This article presents the characteristics of EWOD device with aluminum oxide (Al 2O 3, ε r ≈ 10) deposited by atomic layer deposition (ALD), for the first time as the high-k dielectric for lowering the EWOD driving voltage substantially. The EWOD device of the single-plate configuration was fabricated by several steps for the control electrode array of 1 mm × 1 mm squares with 50 μm space, the dielectric layer of 1,270 Å thick ALD Al 2O 3, the reference electrode of 20 μm wide line electrode, and the hydrophobic surface treatment by Teflon-AF coating, respectively. We observed the movement of a 2 μl water droplet in an air environment, applying a voltage between one of the control electrodes and the reference electrode in contact with the droplet. The droplet velocity exponentially depending on the applied voltage below 15 V was obtained. The measured threshold voltage to move the droplet was as low as 3 V which is the lowest voltage reported so far in the EWOD researches. This result opens a possibility of manipulating droplets, without any surfactant or oil treatment, at only a few volts by EWOD using ALD Al 2O 3 as the dielectric.

KW - Aluminum oxide (Al O )

KW - Atomic layer deposition (ALD)

KW - Digital microfluidics

KW - Electrowetting on dielectric (EWOD)

KW - Single-plate configuration

UR - http://www.scopus.com/inward/record.url?scp=77649238688&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77649238688&partnerID=8YFLogxK

U2 - 10.1007/s10404-009-0511-9

DO - 10.1007/s10404-009-0511-9

M3 - Article

AN - SCOPUS:77649238688

VL - 8

SP - 269

EP - 273

JO - Microfluidics and Nanofluidics

JF - Microfluidics and Nanofluidics

SN - 1613-4982

IS - 2

ER -