The method of preparing fine solder powder (ultra-micro solder powder)

There are various ways to prepare fine solder powder, and five commonly used methods are described below

Analysis of QFN package bridging phenomenon and suggestions for improvement

the causes of QFN package bridging phenomenon mainly include solder extrusion, QFN deformation, and the correspondence between void ratio and bridging.To address these issues, we can reduce the amount of solder paste printed on the inner ring and provide tin space to improve the two aspects.Through reasonable process design and optimisation, we can

Process of solder joint formation in QFN packages

Firstly, due to the smaller size and closer proximity of the peripheral solder joints (i.e. I/O solder joints) to the heat source, they will start to melt earlier than the heat sink pads.This process may cause the QFN package to be slightly lifted locally, but this lifting will gradually disappear as the solder continues to melt.

What are the well-known brands of flux?

Fluxes do play a vital role in the manufacturing industry, especially in the electronics manufacturing industry.There are many of its well-known brands, each of which occupies a place in the market by virtue of its unique advantages and characteristics.Below are some of the well-known flux brands and their characteristics

What are the solder paste viscosity test methods?

There are various methods of solder paste viscosity testing, each with its own specific scope of application, advantages and disadvantages.Below is an overview of several common solder paste viscosity testing methods

Does solder paste expire?

Solder pastes can expire. The shelf life of solder pastes generally ranges from 6 months to 1 year, with finer ultra-micro solder pastes or epoxy pastes having a somewhat broken shelf life of 3-6 months storage life. The specific shelf life can be affected by a variety of factors, including manufacturer's labelling, storage conditions and frequency

Microstructure and mechanical properties of solder joints

There is a strong link between the microstructure and the mechanical properties of the solder joints, such as the cooling rate, creep and fatigue properties, as well as the lead-free alloy properties have a large impact on the solder joint properties. The following are some analyses and further explanations:

The Impacts of Laser and Reflow Soldering on Solder Joints

With the advent of the "post-Moore era", heterogeneous integration based on small chips will become the mainstream of semiconductor packaging. Small chips tend to be packaged in 3D directions to achieve flexible modular integration and system-on-chip integration. It should be considered that 3D packaging will bring some problems. For example, high-