PCB Electronics Assembly

Low-Temperature Soldering

Indium Corporation makes a wide range of alloys that melt or reflow below 180°C and can be used to solve a great many assembly and other challenges.

Low-temperature solder is often used in electronics assembly including for these applications:

• Attachment of temperature sensitive components to printed circuit boards
• Step soldering, when a secondary, lower temperature reflow process is required after a standard SAC soldering process is completed
• Eliminating warpage of thinner chips due to high temperature reflow
• Low melting or low-Tg flex circuitry which are used in cellphones, smartwatches, and many internet-of-things (IoT) devices
• Large area array devices, such as BGAs, to avoid head-in-pillow (HIP) and non-wet-open (NWO) failures

Package-on-Package

Package-on-Package (PoP) assembly is most commonly carried out by printing solder paste onto the substrate and placing the logic chip into the paste. The memory package is then either dipped into a specially-designed PoP flux or solder paste and placed on top of the logic chip. The whole assembly is then reflowed. No-clean processes are used.

Rework

Indium Corporation manufactures a variety of materials for PCB rework, repair, and touch up, including flux-cored wire, liquid rework fluxes, and TACFluxes^®.

Robotic Soldering

Indium Corporation manufactures solder wire for a variety of processes, including automated or robotic soldering for large job lots, or jobs where other processes are not possible. By providing reliable robotic soldering materials, coupled with our soldering expertise and knowledge, we can improve your processes and yields.

Our flux-cored soldering wire gives you no-voiding wire that is consistent in diameter and wound in even layers throughout the spool. Flux-cored wire contains a high-flux volume percentage in the center to facilitate the soldering process and eliminate the need for a separate flux, streamlining automated processes.

Selective Soldering

Selective Soldering is a method of soldering components to a printed circuit board in a way that is faster than hand soldering and consumes less solder than traditional wave soldering. It is becoming known within the industry as one of the most effective soldering methods available, and its usage continues to increase as assemblers transition away from other costlier soldering methods. Indium Corporation manufactures a number of products well-suited for selective soldering applications, such as WF-9945, WF-9948, and WF-9958.

Solder Fortification^®

Obtaining the precise amount of solder to ensure a stronger solder joint is critical in electronics manufacturing. However, miniaturization trends, such as the reduction of stencil thickness and more tightly fitted components, make this increasingly difficult. Solder Fortification^® Preforms can provide the solution for these challenging issues.

Solder Fortification^® Preforms are rectangular shaped pieces of alloyed metal that do not contain any flux. The preform is added to a deposit of solder paste using standard pick and place equipment. Since the alloy for both the preform and the solder paste are the same, the preform will reflow at the same temperature as the solder paste, with the solder paste providing the necessary flux. The preform increases the volume of solder above what could be achieved with just solder paste, especially for applications using stencils with a pitch of 0.3mm or less.

Surface Mount Technology (SMT)

Whether you are qualifying a new product, looking for ways to improve process yields, or upgrading for future capabilities, Indium Corporation has the expertise and products to help you with your PCB Assembly needs.

• Pb-free No-Clean Solder Pastes
• Pb-Free Water-Soluble Solder Pastes
• SnPb Solder Pastes
• Package-on-Package Solder Pastes
• Solder Preforms
• Soldering Fluxes

Wave Soldering

Indium Corporation offers a variety of state-of-the-art and traditional wave soldering products that meet IPC J-STD, Department of Defense, and telecom specifications, as well as customer-specific commercial specifications for wave and selective soldering operations.

Wave soldering is the preferred method of assembly for high-volume, low-complexity circuit boards. Selective soldering is becoming much more common as assemblers need to reliably add a small number of components onto surface mount boards.

Indium Corporation’s technical support and development staff have many years of experience with both wave and selective soldering applications so that they can assist our customers with a variety of materials and process recommendations designed to maximize yield and reduce overall costs. Additionally, we have formed relationships with many of the soldering equipment manufacturers so that we can deliver coordinated solutions.