LPS SOLDER PASTE BASED LOW COST FINE PITCH POP INTERCONNECT SOLUTIONS

• Main Authors: MATAYABAS JAMES C.J, MATHKAR AKSHAY, RARAVIKAR NACHIKET R
• Format: Patent
• Language: English
• Published: 01.10.2015
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

Embodiments describe high aspect ratio and fine pitch interconnects for a semiconductor package, such as a package-on-package structure. In an embodiment, the interconnects are formed with a no-slump solder paste. In an embodiment, the no-slump solder paste is printed in an uncured state, and is then cured with a liquid phase sintering process. After being cured, the no-slump solder paste will not reflow at typical processing temperatures, such as those below approximately 400° C. According to embodiments, the no-slump solder paste includes Cu particles or spheres, a solder matrix component, a polymeric delivery vehicle, and a solvent. In an embodiment, the liquid phase sintering produces a shell of intermetallic compounds around the Cu spheres. In an embodiment, the sintering process builds a conductive metallic network through the no-slump solder paste.