Influence of control parameters on accuracy and reliability of the jet-dispensing process

Jet-dispensing technology is increasingly applied in electronic fabrication because of its high productivity characteristics, and these applications require a high degree of accuracy in the position of the liquid droplets to be dispensed. Therefore, this paper investigates the influence of needle diameter, suction pressure, flow rate, and supplied material pressure of a pneumatic valve-controlled dispenser on drops' positional accuracy and reliability. A Taguchi orthogonal array, signal-noise ratio, and analysis of variance are employed to analyze the influence of these control parameters. The analysis reveals that flow rate has the most impact on both criteria. Meanwhile, the variation of supplied material pressure negligibly impacts the quality of the process. Additionally, the quality significantly improves using a small needle in the case of minimum suction pressure value. The average dot-shift can achieve 3.2 mu m with a standard deviation of 2.12 while using the needle diameter of 18 G-size, suction pressure of 0.8 Pa, flow rate of 0.1 mg/s, and supplied material pressure at 150 kPa.