Electron Beam Testing of Electronic Packages Using a Continuously Rotating Table
Original Publication Date: 1986-Jan-01
Included in the Prior Art Database: 2005-Mar-08
In the manufacture of multi-layer ceramic substrates for semiconductors, electron beam testing of the substrates is used to test the substrate interconnections. This technique has deflection range and spot resolution limitations which do not make it viable for one-step inspection of large samples. The method described provides a continuous or sequential rotation of the samples being inspected to overcome these limitations. Systems currently in use typically have a 1-2 mil resolution over 90-100 mm square deflection area. These parameters can only be expanded marginally, so that larger sample sizes cannot be accommodated without some modification to the operating procedures. One method of handling large samples, shown in Fig. 1, is to use a step-and-repeat technique.