P‐103: Ultra Fine Drop Volume Measurement Technic using Chromatic Confocal Sensor(CCS) for Quantum Dot Inkjet Printing Process

In this study, ultra fine drop (<10pl) volume measurement technics were developed using chromatic confocal sensor(CCS). A printing pattern was printed on the substrate by printing equipment, and each sensor measures the height of the drop surface and by integrating them, the drop volume could be determined. To evaluate its performance, measurement accuracy, and the repeatability was determined. The measurement accuracy can be obtained by comparing the same drop volume measured by the confocal microscope. For the measurement repeatability, the same drop volume was measured for several times and its maximum and minimum value was used to determine. As a result, CCS showed a good measurement performance with measurement accuracy of more than 0.90 (R 2 in least square) and measurement repeatability of over 0.95.