A New OEW Microfluidic Device based on p-n Junction

Compared with the electrowetting on dielectric (EWOD) microfluidic device, optoelectrowetting (OEW) microfluidic device does not need to control the on-off of single electrode, but only needs to change the lighting condition to control the droplet, simplifying the peripheral control device and improving the stability of the device. The contradiction between the operating voltage and the driving force exists in the existing OEW device. To solve this problem, this paper proposes an OEW device based on diode structure, which uses the photoelectric effect of the diode connected in the DC circuit to control the movement state of the droplet. In this paper, the feasibility of the OEW device with pn structure is theoretically analyzed. Compared with the previous OEW device, under the same applied voltage and the same illumination difference, the potential difference between the diodes in the new device will be significantly larger than the potential difference between the photoresistors, which will effectively improve the driving force of the DC drive.