Electron-beam MCM testing and probing

IC probing with electron beams is already common practice for design verification and failure analysis. E-beams can also be applied to substrate testing offering flexibility for further MCM developments. A new electron beam MCM substrate tester has been developed and installed in the Siemens-Nixdorf fabrication line. It provides a spot size of below 25 μm to probe pads in a 30 cm×30 cm field without mechanical movement and without electrical contact. The tester is automated for fabrication environment and ease of operation. More than one hundred substrates have already been tested on the system while not missing any defect. Diagnostic methods using electron beams can be transferred from IC to MCM application, However, conventional e-beam probe stations cannot handle the size of an MCM substrate. Therefore, a new system was developed allowing the beam to probe an area of 100 mm×80 mm