A Wafer-Level Sn-Rich Au—Sn Bonding Technique and Its Application in Surface Plasmon Resonance Sensors

Abstract

Sn-rich Au-Sn solder bonding is systematically investigated. High shear strength (64 MPa) and good hermeticity (a leak rate lower than 1 × 10 −7 torr•l/s) are obtained for Au-Sn solder with 54 wt% Sn bonded at 310 ∘ C. The AuSn2 phase with the highest Vickers-hardness among the four stable intermetallic compounds of the Au-Sn system makes a major contribution to the high bonding strength. This bonding technique has been successfully used to package the Surface Plasmon Resonance (SPR) sensors. The Sn-rich Au-Sn solder bonding provides a reliable, low-cost, low-temperature and wafer-level hermetic packaging solution for the micro-electromechanical system devices and has potential applications in high-end biomedical sensors.

Solid-Liquid Interdiffusion (SLID) Bonding of p-Type Skutterudite Thermoelectric Material Using Al-Ni Interlayers

“…One promising interconnect technology for high-temperature microelectronic packaging is solid–liquid interdiffusion (SLID) bonding [14], also called transient liquid-phase bonding (TLPB) [15], and diffusion brazing [16]. This technique was developed in the 1970s by Duvall, et al [17] and constitutes a suitable alternative to high-temperature furnace brazing operations while being commonly considered as the best alternative for solder bonding e.g., for wafer/chip stacked bonding for advanced micro-electro-mechanical systems (MEMS) [18,19] and in sensors manufacturing [20]. The SLID bonding technique is based on binary interlayer systems comprising a high-melting-point material, T M HIGH , and a low-melting-point material, T M LOW , which is heated to its molten state, resulting in the formation of intermetallic compounds (IMCs) through a diffusion-reaction mechanism.…”

Reliability study of Au-in solid-liquid interdiffusion bonding for GaN-based vertical LED packaging

“…In semiconductor fabrication, Au-Sn bonding has been widely investigated, and it has been used in microelectromechanical systems (MEMS), die attachment, and high-temperature sensors [1][2][3]. Thus far, the remelting temperature has been limited to ~310 °C [4].…”