LabVIEW program for the process control of dieletrophoretic assembly of carbon nanotubes

Abstract

LabVIEW programs have been widely applied to instrument control for various applications in engineering. In this paper, carbon nanotube (CNT) assembly by dielectrophoresis (DEP) is investigated and LabVIEW is used to control the DEP for increased degree of process automation. Real-time electrode gap impedance is monitored during DEP and is set as feedback control signal to stop the process. A precision LCR meter generates an alternating current (AC) voltage for DEP and simultaneously measures the gap impedance. Through calling some main performance programs in LabVIEW, the LCR meter is initialized and the code can be designed and read into the control programs via the general-purpose interface bus (GPIB) communication. The impedance decreases suddenly when CNTs are deposited across the gap. The control programs contribute significantly to realizing CNT assembly with specific requirements such as with a predefined assembly resistance, a predefined assembly time or a predefined small number of CNTs.