• Alloy: Indalloy 281 (58Bi/42Sn)
• Type 3 powder (90 percent metal load)
• Quantity: 500g jar
• A low-temperature, Pb-free solder paste designed for assembly processes using Bi-based and In-based low-temperature alloys
• Formulated for use with the eutectic 58Bi/42Sn, 57Bi/42Sn/1Ag, and 57.6Bi/42Sn/0.4Ag alloys

As a leader in soldering technology, Indium Corporation offers a number of solder pastes for Pb-free assembly. Indium offers many different alloy choices and flux technologies to solve many of your process challenges.

Indium Corporation’s Pb-free solder pastes are ideal for miniaturized components and fine-pitch assembly. They provide first-class printing and robust reflow performance and are all designed to AVOID THE VOID®.

Avoid the Void

Avoid shortened product life; avoid field failures; avoid customer dissatisfaction, plus a whole lot more with Indium Corporation’s advanced solder paste technology.

Indium Corporation’s suite of solder pastes offers formulations designed to deliver low-voiding, plus enhanced benefits such as improved response-to-pause, stability, HiP minimization, reliable in-circuit testing, and enhanced SIR performance.

Indium5.7LT is an air reflow, halogen-free, no-clean solder paste designed for assembly processes using eutectic SnBi and SnBiAg alloys. This paste is a moderate residue product with exceptional wetting capabilities. The low activation temperature of Indium5.7LT, in combination with the SnBi alloy, can be especially useful as a low-temperature, Pb-free solution.

Packaging

Standard packaging for Indium5.7LT is 500g jars and 600g cartridges. For dispensing applications, 10 and 30cc syringes are standard. Other packaging options may be available upon request.

Storage and Handling Procedures

Refrigerated storage will prolong the shelf life of solder paste. Solder paste packaged in syringes and cartridges should be stored tip down

Solder paste should be allowed to reach ambient working temperature prior to use. Generally, paste should be removed from refrigeration at least 2 hours before use. Actual time to reach thermal equilibrium will vary with container size. Paste Mesh Size Type 3 Type 4 2,000 temperature should be verified before use. Jars and cartridges should be labeled with date and time of opening.

Stencil Design:

Electroformed and laser cut/electropolished stencils produce the best printing characteristics among stencil types. Stencil aperture design is a crucial step in optimizing the print process. The following are a few general recommendations:

• Discrete components—A 10–20% reduction in stencil aperture area may significantly reduce or eliminate the occurrence of mid-chip solder beads. The “home plate” design is a common method for achieving this reduction.
• Fine-pitch components—A surface area reduction is recommended for apertures of 20mil pitch and finer. This reduction will help minimize solder balling and bridging that can lead to electrical shorts. The amount of reduction necessary is process-dependent (5–15% is common).
• A minimum aspect ratio of 1:5 is suggested for adequate release of solder paste from stencil apertures. The aspect ratio is defined as the width of the aperture divided by the thickness of the stencil.

Cleaning

Indium5.7LT is designed for no-clean applications; however, the flux can be removed, if necessary, by using a commercially available flux residue remover.

Stencil Cleaning: This is best performed using an automated stencil cleaning system for both stencil and misprint cleaning to prevent extraneous solder balls. Most commercially available stencil cleaning formulations including isopropyl alcohol (IPA) work well.

Compatible Products

• Rework Flux: TACFlux 057