Operational Regimes and Physics Present in Optoelectronic Tweezers

• Published in: Journal of microelectromechanical systems Vol. 17; no. 2; pp. 342 - 350
• Main Authors: Valley, Justin K., Jamshidi, Arash, Ohta, Aaron T., Hsu, Hsan-Yin, Wu, Ming C.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.04.2008; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied fluid mechanics; Biomedical optical imaging; Buoyancy; Conductivity; Devices; Dielectrophoresis; Dielectrophoresis (DEP); Electrodes; Electrokinetics; electrothermal (ET) flow; Exact sciences and technology; Fluid dynamics; Fluidics; Fundamental areas of phenomenology (including applications); Glass; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; light-induced ac electroosmosis (LACE); Mathematical models; Mechanical instruments, equipment and techniques; Micromechanical devices and systems; Nanobioscience; Nanocomposites; Nanomaterials; Nanostructure; Optical devices; Optical sensors; optoelectronic tweezers (OET); Optoelectronics; Physics; Voltage; Optoelectronics; Electrokinetics; Electrothermics; Buoyancy; Optoelectronic devices; Experimental study; Finite element method; Dielectrophoresis (DEP); electrothermal (ET) flow; Temperature effects; Electroosmosis; optoelectronic tweezers (OET); light-induced ac electroosmosis (LACE); Modelling; Micromanipulation; Dielectrophoresis; Microelectromechanical device; Heat transfer; Fluidics
• ISSN: 1057-7157; 1941-0158
• DOI: 10.1109/JMEMS.2008.916335

Optoelectronic tweezers (OET) are a powerful light-based technique for the manipulation of micro- and nanoscopic particles. In addition to an optically patterned dielectrophoresis (DEP) force, other light-induced electrokinetic and thermal effects occur in the OET device. In this paper, we present a comprehensive theoretical and experimental investigation of various fluidic, optical, and electrical effects present during OET operation. These effects include DEP, light-induced ac electroosmosis, electrothermal flow, and buoyancy-driven flow. We present finite-element modeling of these effects to establish the dominant mode for a given set of device parameters and bias conditions. These results are confirmed experimentally and present a comprehensive outline of the operational regimes of the OET device.