PBGA Reliability of Lead Free Solder Balls Assembled with Tin Lead Solder Paste for Harsh Environment Electronics

Abstract

The demand for high-temperature electronics is growing rapidly in the automotive industry. This stems directly from the fact that these electronics are being transferred from their passive environments to under-the-hood locations, specifically on the engine or transmission. The electronics not only have to withstand high temperatures in excess of 150ºC but also maintain superior levels of reliability at no added cost. To meet this criterion, the plastic ball grid array (PBGA) electronic packages have been successfully integrated into the design of under-the-hood controllers. Until recently, the research and design of the PBGA packages have incorporated the traditional tin lead solder balls assembled on tin lead solder paste. But lead free regulations set forth in Europe, Japan, and China has put pressure on the Unites States electronics industry to convert to lead free manufacturing. Due to different timetables between the electronic component supplier and the manufacture, direct conversion to lead free manufacturing is not feasible. For PBGA packages, hybrid interactions between the solder balls and solder paste will exist. The primary focus of this research was to evaluate the reliability of the hybrid combination, namely lead free PBGA packages assembled on tin lead solder paste.