Our Products #5141417

Indium Corporation is a leading joining and bonding materials innovator for medical, aerospace, optoelectronics, and automotive applications.
When even 10 ppm of contamination can cause process and application failures quality counts. Indium Corporation casts our alloys, which enables us to closely control the process from start to finish and ensure purity.
High-Temperature Solder and Braze Materials Deliver:
Highest tensile strength of any solder
High melting point is compatible with subsequent reflow processes
Pb-free and RoHS compliant
Superior thermal conductivity
Resistance to corrosion
Superior thermal fatigue resistance
Good joint strength
Excellent wetting properties
Resistance to oxidation

Indium Corporation manufactures electroplating anodes in several forms:
With an embedded hook
Bulk indium metal anodes
Ingots
Indium foil
Indium ribbon
Anodes with embedded hooks are made from Monel alloy. They are shaped dimensionally true so the anode rod will hang straight. Anodes are available with 7 or 5 hooks.

Indium-electroplated films have many industrial applications that take advantage of the unique physical and chemical properties of the indium metal, such as its low melting point, low vapor pressure, inherent softness and malleability, cold welding properties, anti-friction properties, and alloy hardening properties. Indium electroplating applications include surface preparation, decorative finishing on metals and plastics, sealing, aircraft bearings, and electrical interconnects in microelectronic devices. Our complete set of electroplating products includes all materials needed for indium electroplating processes:

Epoxy fluxes are often used in no-clean SMT component attach applications. The solder bumps on wafer level CSP, micro BGA or BGA packages are dipped in epoxy fluxes, or the flux is applied to the substrate via a jetting process. The assembly is then reflowed, and the epoxy flux acts to both clean up the solder joints before reflow, and to reinforce the final joint from the cured polymer.

Features
Eliminates the need for manual fluxing
Eliminates excessive flux residue
Increases productivity
Applies flux precisely where it is needed
Applies a uniform amount every time
Introduction
Flux-Coated Preforms eliminate the costly production step of separate fluxing and increase throughput yields. Flux Coatings for Preforms are available in no-clean and rosin-based chemistries with a variety of activity levels to suit your substrate metallizations.
Flux Coatings
Indium Corporations unique coating process can control the amount of flux to tight tolerances. Flux Coatings are measured and applied by weight percentage. The coatings range from 1-3% and standard tolerances are controlled at +- .5%. Coatings can be applied to most sizes and shapes of preforms.
Using Flux-Coated Preforms in Soldering
For certain soldering applications, flux-coated preforms may offer the greatest number of benefits over other more conventional forms of solder. For applications other than active device manufacture, flux can be incorporated as an integral part of the preform design to meet customer needs for the precise amounts of flux, easy automation, and elimination of costly separate flux applications.
In general, fluxes should be avoided in active device assembly due to the difficulty in removing the flux residue after soldering. If care is taken to ensure the joining surfaces and the preforms are thoroughly clean, and if a reducing atmosphere at 350C is used, flux coating is usually not necessary.
Flux coated Indalloy soft solder preforms eliminate the necessity of manually applying external liquid fluxes in operations such as vapor phase soldering of back-plane wiring assemblies and capacitor manufacture. Flux-coated preforms are manufactured with the exact amount of flux required for the specific application, providing a high degree of consistency from one bond to another. Flux percentages can be specified between 0.5% and 3% by weight with a tolerance of 0.5%. The most popular percentage being 1.0% by weight.
Indalloy flux types are available in non-activated pure gum rosin (type R), mildly activated rosin (type RMA) and fully activated rosin (type RA). RMA fluxes have a small but highly effective amount of an activator added to increase fluxing action over the R type. RA fluxes contain a small amount of an amine hydrochloride activator that provides superior fluxing action, as compared to R and RMA type fluxes. RA flux finds use in soldering assemblies where a high degree of fluxing action is desired, e.g. soldering to tarnished copper or nickel plate. RSA, an enhanced version, is also available for preform coating. This flux is the strongest of the rosin types. NC-7 and NC-9 fluxes are specially formulated RMA type fluxes that, along with the R type flux, leave nonconductive and non-corrosive residues that can safely be left on an assembly without fear of corrosion. However, for aesthetic or visual inspection purposes, the flux residue can be removed using a bipolar solvent to remove both the rosin portion and the ionizable activator portion of the flux. This is most often accomplished using vapor degreasing equipment.
In summary, the use of Indalloy flux-coated preforms can result in the following advantages:
All fluxes used to coat preforms, when reflowed using a standard Sn63 profile, pass SIR tests.
The precise amount of flux and alloy are delivered to the solder joint.
The costly production step of separate fluxing is eliminated.
Bonding is faster because the flux is positioned where it is required, next to the surfaces to be joined, unlike the case with flux-filled preforms.
Because less flux is used, post solder cleaning is easier.
The flux quantity is uniform in thickness and consistent in amount from piece to piece.
The dull, flux-coated surface is ideal for IR reflow.
Since the flux on flux-coated preforms contains no solvent, voiding is typically less than when manually applying liquid flux to uncoated preforms.

Indium Corporation's flux pens utilize a spring-loaded applicator tip to deliver a controlled amount of flux to the work surface. The user friendly pin-point applicator is ideal for touch-up and light assembly work. To apply, simply depress the tip of the flux pen against the work area to start the flow of the applicator tip.
Indium Corporation flux pens come in Pb-free and SnPb, no-clean and water wash.

The flip-chip process involves taking the singulated die from a wafer mounted on a wafer dicing tape, inverting ("flipping") them and placing them onto a substrate. The substrate may be a printed circuit board, a ceramic substrate, or (in the case of 2.5D and 3D assembly) an interposer.
Copper pillarsolder microbumps are emerging as a standard flip-chip solder bump replacement in many parts of the semiconductor assembly industry, from standard chip-attach to power devices using flip-chip on leadframe as assembly technologies. For logic and similar devices, substrate metallization (landing pad) technology has also shifted from solder-on-pad (SoP), manufactured from printed and reflowed and cleaned solder paste, to individual solder balls. The technology is now moving to simple organic solderability protectant (OSP) on copper.
Water-soluble fluxes, which may be applied by dipping or spraying, have long been used in flip-chip assembly, but their long history of utility is coming to a close as a number of factors makes the move to no-clean inevitable in the high-volume sub-130micron copper pillar era.
The use of copper pillar instead of solder bumps has meant that chip-substrate clearances and finer pitches do not necessarily move in lock-step with each other. However, copper pillar heights of 40-60 microns (and even shorter than this in the near future) combined with fine pitch, makes cleaning extremely complex. Aqueous (water-based) cleaning becomes more complex with fine pitch flip-chip attach as it becomes increasingly difficult to get the cleaning solution under the chip to dissolve the residues, and then to carry the residue-containing solution out from under the chip.
A recent emerging failure mode caused by cleaning involves solder joint damage during aqueous jet impingement. This failure mode is believed to be driven by a combination of: very small diameter microbumps; the move from hemispherical to very thin solder microbumps on copper pillar (reduced joint compliance); and low CTE, low-cost, and low layer count (thinned) substrates. In these circumstances, a move towards an ultra-low residue no-clean flux is inevitable, although new failure modes continue to appear, being driven by the smaller dimensions. For this reason, Indium Corporation has introduced a new ultra-low (ULR) flux called NC-26-A for both current and emerging applications.

The ball-attach process for BGA and PGA packages uses a flux that is usually applied via pin-transfer from a dipping tray. Solder spheres (solder balls) are then placed into the deposits and the whole assembly is reflowed. BGA fluxes are usually water soluble, while PGA fluxes are often very reactive no-clean materials.
Indium Corporation most popular ball-attach fluxes include:

WS-575-C-RT: a halogen-compliant, room temperature stable, one-step flux that eliminates the need for pre-fluxing
WS-3600: a robust, halogen-containing flux that works well under challenging conditions
NC-585: designed for PGA applications; eliminates issues caused by cleaning while still ensuring good
solderability