A Non-Contact Dispensing Inker for Dice Marking of Wafer Detection

To make up the insufficiency and instability of contact inkers that are currently used for defective dice marking in integrated circuit production, a noncontact jetting inker is introduced in this paper. The volume of fluid (VOF)/continuum surface force (CFS) model is used to establish the mathematical description of jetting liquid into ambient air, and actuating pressure waveform is estimated for droplet generation. Subsequently, numerical simulation is taken to reveal the dynamic characteristics and generating mechanism of droplet jetting. Emergence and tolerance of satellite drops are also interpreted. With simple structure, a jetting inker is presented for ink dot distribution. The influences of actuation and nozzle size upon ink jetting performance are analyzed and numerical results are verified. Both simulation and experimental data indicate that the effectiveness, uniformity, and cleanness of dispensing performance can meet the requirements of wafer dice marking.