A simple thermo-compression bonding setup for wire bonding interconnection in pressure sensor silicon chip packaging

Abstract

In the process of piezo-resistive pressure sensor packaging, a simple thermo-compression bonding setup has been fabricated to achieve the wire bonding interconnection of a silicon chip with printed circuit board. An annealed gold wire is joined onto a pad surface with a needle-like chisel under a force of 0.5-1.5 N/point. The temperature of the substrate was maintained in the range of 150-200°C and the temperature of the chisel was fixed at around 150°C during wire bonding operation. The tensile strength of the wire bonding was measured with a bonding tester by the destructive-pulling experiment and was found to be at the average of 132 mN/mm 2 . The microstructure of the bonding point was examined by scanning electron microscopy. The interface of the thermo-compression boning was shown to possess an acceptable level of reliability for a micro-electromechanical system (MEMS)-based device. The results showed that this setup can be easily operated for fabrication and is suitable for fabricating not only low-cost pressure sensors, but also other MEMS devices.

Research of MEMS pressure sensor stability with PDA-NFL circuit

“…The geometry of assembly structure for pressure sensor chip PDA-NFL has a significant influence on the errors, because the RMS relaxation from all kinds of chip-to-body bonding has effect by time and temperature changing (the second factor about long-term stability from the Introduction). It is possible to consider different types of chip PDA-NFL micro-assembly and other MEMS in general before the moment of connection with metal, ceramic, plastic or other materials cases [80,81]: hydrophilic or hydrophobic direct bonding of silicon [82], anodic bonding [83], coupling through glass (frit) [84,85], eutectic [86,87], adhesive bonding [88,89], reactive compound [90,91], thermal compression [92,93] or laser-assisted coupling [94]. There are also rather exotic micro-assembly technologies, such as in the design of the PS 3 [95].…”