Glass substrates enable advanced semiconductor packaging: Design rules for via-via distances based on mechanic reliability

  
  Dr. Martin Letz

  senior principal scientist，SCHOTT AG

Abstract:

Mechanic reliability of a brittle material is dominated by surface defects. In combination with mechanic stress, surface defects lead to failure. Relevant surface defects are so small, that it is between impossible and impractical to detect all of them. Therefore statistic methods need to be applied to investigate failure mechanism. In the current work we calculate the stress distribution as a function of via-via distance and experimentally determine the threshold – approximately two times the via diameter as a center-to-center distance --, where the stress increase between neighboring vias starts to affect the mechanic stability. The impact on the mechanic stability is seen as an increase of failure rate in a Weibull statistic of a series of ring-on-ring breakage tests.

Speaker's Biography: 

Martin Letz works with SCHOTT, a special glass company, as a senior principal scientist in the central R&D. He joined SCHOTT in 2001 and was involved in several projects regarding materials for semiconductor structuring. Since several years he focusses on glasses and glass ceramics for electronic applications and their properties. One focus is on materials for antenna and filter structures for wireless data transfer. A second focus is on heterogeneous integration and glass core based semiconductor packaging. Prior to that he received his PhD in solid state physics from the University of Stuttgart in Germany and had several positions in research institutions and Universities (Tartu University (Estonia), Max-Plack Institut (Stuttgart, Germany), Queens University (Kingston, Canada), University of Mainz (Germany)) working on different aspects of strong correlations in condensed matter.