The effect of Yttrium addition on the microstructure and mechanical properties of Sn-Zn eutectic alloy, which has been attracting intensive focus as a Pb-free solder material, was investigated in this study. Phase equilibrium has been calculated by using FactSage® to evaluate the composition and fraction of equilibrium intermetallic compounds and construct a phase diagram. In the case of Sn-8.8...

Adhesive bonding is a well-known technics to assembly dies or wafer on a host substrate through polymer or solder bumps. To combine electronic and photonic systems on a single chip, we propose hereby to use AuSn alloy as bonding medium combined to waferscale technology and post-bonding III-V processing alleviating so the need of alignment accuracy between wafers. For instance, high density LED’...

In a typical electronic assembly, many of the solder joints undergo multiple reflow cycles during the course of a complete manufacturing process from wafer bumping to the board level assembly. Effect of these reflows on the solder joint formation and its evolution during these cycles was investigated. In the first part of the study, small size BGA’s were assembled with 12mil spheres of a number...

The goal of the present work is to investigate the effects of the addition of Sb (0, 3 and 6 wt%) on structure, melting, corrosion and mechanical properties of Sn-Bi eutectic solder alloys. The mechanical properties of the bulk Sn-Bi-Sb solders were higher as the amount of antimony increases, making compressive strength augment from 65 MPa to 100 MPa when 6 wt% Sb was incorporated to the Sn-Bi ...

Although the primary driver for the current interest in developing lead-free soldering is global market pressure for more environmentally friendly products, the main concern continues to be lead contamination from end-of-life electronic products in landfill sites. In response to existing and impending legislation in Europe and Japan for the elimination of lead from electronic products, the indu...

A microscopic investigation has been made on the shearing of one leaded and two leadfree solders by using an in situ SEM method. A shear lap joint specimen is designed and fabricated to accommodate a thin layer of solder alloy between copper strips. A non-contact method that measures strains in a very narrow area in the solder was applied. A laser grid was also used on the copper strip for meas...

BACKGROUND AND AIMS In order to fabricate prostheses with high accuracy and durability, soldering techniques have been introduced to clinical dentistry. However, these prostheses always fail at their solder joints. The purpose of this study was to evaluate the effect of gap distance on the tensile strength of base metal solder joints. MATERIALS AND METHODS Based on ADA/ISO 9693 specifications...

With the upcoming European ROHS legislation and other global movements to lead-free assembly, the NEMI lead-free rework group investigated and developed lead-free rework processes for medium to high-end computer products. The work concentrated on development of lead-free hot air convection rework for PBGA, CBGA, and uBGA, and lead-free hand soldering rework for TSOP and 2512 chip components on ...

A micro-impression creep machine was designed and developed, adopting a small punch in diameter of 150 um, displacement gage with sub-μm-scale accuracy, and a load-cell with mN-scale accuracy of in an effort to investigate the creep behavior of a small solder ball with a diameter of less than 1 mm. The creep behavior of a lead-free solder ball (Sn-3.0Ag-0.5Cu) with a diameter of 760 μm was inve...

As an alternative to the time-consuming solder pre-forms and pastes currently used, a co-electroplating method of eutectic Au-Sn alloy was used in this study. Using a coelectroplating process, it was possible to plate the Au-Sn solder directly onto a wafer at or near the eutectic composition from a single solution. Two distinct phases, Au5Sn and AuSn, were deposited at a composition of 30at.%Sn...