Continuous Path Motion Control
Recently, a new software feature has been developed for jetting underfill for new flip chip devices and new die configurations. It eliminates the need for backtracking, acceleration, and deceleration, and thus saves time, increasing UPH. It is referred to as Continuous Path Motion Control, and it is a Nordson ASYMTEK proprietary, patent pending, technology. In this process, instead of stopping to move between die, backtracking, ramping to speed, dispensing, and decelerating, the dispense head maintains a continuous speed and direction throughout the process.
This continuous path software feature saves significant time when spacing between die is small, by enabling continuous motion at high dispense speeds. The dispense head is programmed to jet (dispense) the exact amount of fluid in precisely the correct place. As a result, UPH will increase for underfill dispensing. However, cycle time savings is not an exact reflection of UPH improvement, because the underfill process involves many steps. These include loading/unloading, detecting the fiducials, height sensing, and dispensing (or jetting), which includes both dispensing and non-dispensing movements.
New applications that require underfilling of parts that are smaller and closer together, especially where volume production and speed are required in manufacturing, are pushing manufacturers to explore new methods for applying underfill. Using continuous path motion control enables the manufacturer to take advantage of the increased speed that results from thinner, more closely spaced die.
Download the paper to learn, in more technical detail, about Continuous Path Motion Control:
Underfilling Flip Chip Die Using Continuous Path Motion Control - A. Morita
Comparing Continuous Path Motion Control (on the left) to the conventional (on the right) method of underfilling. Click on the picture to open up the video player.
Related links regarding Continuous Path Motion Control and Underfill