PCBA Tech - SMT process materials and medical electronics SMT precautions

1. These craft materials used by SMT chip manufacturers

Production efficiency is one of the foundations of SMT placement processing. When designing and establishing an SMT production line, it is necessary to select appropriate process materials according to the process flow and process requirements. SMT process materials include solder, solder paste, adhesives and other solder and chip materials, as well as fluxes, cleaners, heat transfer media and other process materials. Today, Weilishi will introduce the main role of assembly process materials.

These process materials used by SMT chip manufacturers

(1) Solder and solder paste

Solder is an important structural material in the surface assembly process. Different types of solder are used in different applications to connect the metal surfaces of the objects to be soldered and form solder joints. Reflow soldering is a kind of solder paste, a kind of solder, and the viscosity of SMC/SMD is fixed in advance.

(2) Flux

Flux is an important process material in surface assembly. This is one of the key factors affecting welding quality. It is necessary in various welding processes, and its main function is flux.

(3) Adhesive

Adhesives are adhesive materials in surface assembly. In the wave soldering process, an adhesive is usually used to pre-fix the component to the SMT. When the SMD is assembled on both sides of the SMT, even if reflow soldering is used, the adhesive is often applied to the center of the SMT land pattern to enhance the fixation of the SMD and prevent the SMD from shifting and dropping operations during assembly.

(4) Detergent

The cleaner is used for surface assembly to clean the residue left on the SMA after the soldering process. Under current technical conditions, cleaning is still an integral part of the surface mount process, and solvent cleaning is the most effective cleaning method.

SMT process materials are the basis of the surface mount process, and different assembly processes and assembly processes use corresponding assembly process materials. Sometimes the materials used will vary according to subsequent processes or different assembly methods in the same assembly process.

2. Matters needing attention in the processing of medical electronic SMT patches

Since the new crown epidemic in 2020, the medical industry has ushered in a new round of growth, and more and more medical equipment companies have also ushered in explosive growth. At the same time, it has also brought new challenges to SMT patch factories.

What matters should be paid attention to in the processing of medical electronic SMT patches, medical electronic products have their own special requirements:

Whether it is medical testing equipment or medical auxiliary tools and equipment, it needs to be very high in use, and things about life cannot be approximated, left or right, and so on.

High stability: Especially for medical diagnosis and medical auxiliary tools and equipment, a high degree of stability is essential. Diagnosis in the diagnosis stage and application stability in the clinical application stage.

Taking into account the special requirements of medical equipment, for medical electronics SMT patch processing plants, it is necessary to strengthen the quality control of SMT patch processing.

1. Quality control of components: For the control of medical electronic components, first of all, the quality must be controlled from the source of purchase. After the purchase is completed, IPQC needs to conduct a full inspection of the components, seal the samples and store them in the warehouse, and special BGA and IC must be stored in a moisture-proof cabinet.

2. Solder paste control: The patch processing of medical electronics must select and store solder paste according to the characteristics of the product. The stirring and the addition of flux in the application process must be strictly controlled.

3. Solder joint control: After the quality of components and solder paste is completely OK, the control of solder joints determines the quality of SMT chip processing. Simply put, the quality of solder joints determines the quality of chip processing.

4. Static electricity control: The instantaneous discharge of static electricity can reach several thousand/w. The damage to BGA and IC components is invisible and potential damage. Medical electronics need to deal with considerable data in the application. If the core components are damaged by static electricity, they will be lost. Stability will affect the stability of the product.

In addition, in the SMT patch processing of medical electronics, there are not only the above four points, but also many aspects that require manufacturers to work hard. To be truly responsible for the product and the user of the product is a problem that the manufacturer must face.