Home Deutsch Suche
You are here:
News Schwingungsanalyse Positionierruettler

Operating Vibrations

Design of a vibration positioner for ICs

In a test handler, semiconductor devices are reloaded between different containments several times. Because the containments have different grid tolerances, the ICs have to be fine positioned after reloading them into grids with smaller tolerances. A suitable oscillating conveyor should be developed in order to realize this fine positioning.

In a first step, a suitable vibration exciter was chosen. In the present case a pneumatic piston vibrator was selected. A directed transport is achieved by the incline of the piston axes with respect to the plate normal.

Additionally, the dynamic behavior of the swinging plate was designed. In order to achieve a uniform vibration transport, the bending and torsional natural frequencies of the swinging plate should be well above the frequency range of operation. A suitable decoupling between swinging plate and remaining structure should ensure that the rigid body natural frequencies of the swinging plate are well below the frequency range of operation.

Finally, time-step simulations of the transport mechanism were performed for several values of static and sliding friction between IC and swinging plate. By this means, the resulting transport velocity can be estimated and the optimum inclination of the piston vibrator can be determined.

The vibration positioner straightaway fulfilled all requirements in prototype tests. By default, new test handlers are equipped with it.

Please read the complete article.

© ISMB Elbs GmbH