Title :
A mold and transfer technique for lead-free fluxless soldering and application to wafer-level low-temperature thin-film packages
Author :
Stark, Brian H. ; Najafi, Khalil
Author_Institution :
Center for Wireless Integrated Microsyst., Michigan Univ., Ann Arbor, MI, USA
Abstract :
This paper demonstrates a technique to pre-mold and transfer lead-free solder balls for MEMS/electronics packaging applications. A reusable bulk micromachined silicon wafer is used to mold a solder paste and remove excess flux prior to transfer to a host wafer that may contain released MEMS. This technique has been used to fabricate low temperature thin film vacuum packages. Long term (>5 months) reliability of these packages at room temperature and pressure is demonstrated through integrated Pirani gauges. Data from preliminary accelerated lifetime testing (thermal cycling and autoclave soaking) is also offered.
Keywords :
electronics packaging; micromechanical devices; reliability; soldering; thin films; transfer moulding; 293 to 298 K; MEMS; Si; autoclave soaking; electronics packaging; integrated Pirani gauges; lead free fluxless soldering; lifetime testing; microelectromechanical system; micromachined silicon wafer; mold technique; reliability; room temperature; solder balls; solder paste; thermal cycling; transfer technique; wafer level low temperature thin film vacuum packages; Electronic packaging thermal management; Electronics packaging; Environmentally friendly manufacturing techniques; Lead; Micromechanical devices; Silicon; Soldering; Temperature; Transistors; Wafer scale integration;
Conference_Titel :
Micro Electro Mechanical Systems, 2004. 17th IEEE International Conference on. (MEMS)
Print_ISBN :
0-7803-8265-X
DOI :
10.1109/MEMS.2004.1290510
