Indium Corporation Blogs

NanoFoil^® can be packaged in tape & reel, bulk containers, or waffle packages. Here are the main advantages of each type of packaging:

• Tape & Reel: great choice for high-volume automated pick & place equipment

• Waffle Pack: perfect for hand placement or low-volume automated placement machines

• Bulk: most economical way to order

Packaging NanoFoil^® is actually a lot like packaging standard solder preforms. (Here is a complete list of our packaging options for preforms.)

Did you ever hear the expression, "think like a 12-year-old"?  Meaning a 12-year-old has enough learning to address a problem but not so much experience that they rule out possible solutions.

I have a five-year-old nephew who just loves to figure out how things work and how to use them.  The other day at a picnic as all of us adults tried without success to unscrew the top to a giant container of pretzels he pointed out that there was a piece of plastic that had to be pulled off first to release the lid.  Now in my own defense it wasn't well marked and he was right at the eye level to see the key bit of plastic, but still he solved with his brain what we couldn't solve with our muscle.

I don't want to say we have a lot of 12-year-old minds (or even 5-year-old minds) working here, but I have seen a lot of innovation here at Indium.

One of the most interesting innovations we have developed (and possibly simplest) is Solder Fortification® Preforms.  There are many instances when solder paste stencilling just doesn't leave enough solder paste to form a strong enough joint.  Either the joint has additional strength requirements (like a connector) or a thin stencil is being used and there is no way to get enough solder down efficiently.

The solution is to add a solid piece of solder (no flux added) into the paste deposit to increase the volume of solder.  These solder preforms come in standard sizes (similar to component sizes), standard alloys (to match your solder paste alloy) and are packaged in tape and reel so your in line pick and place equipment can easily be used to add the solder preform.  You can try out an evaluation reel through our ecommerce site or by contacting us at esolders@indium.com.

 

Solderspheres or solder spheres, or even solder balls: whatever you call them, Indium Corporation has been making them for years and has rightly acquired the reputation for doing whatever it takes to meet our customers' unique needs.

Unique Alloys:

Hard to find alloys (like multipart alloys; low-melting alloys and even gold/tin (80Au/20Sn)) are our bread and butter. As "Indium Corporation" it should be no surprise that we lead the world in our ability to supply low-melting indium-alloy solder spheres, as well as other forms of these alloys, such as engineered solders or solder pastes.

Unique Quantities:

We don't want you to buy more than you absolutely need. If you just want 100 spheres, we can easily do that: if you want more - we can do that, too. But remember that, because each customer's need is unique, our prices may be higher than our competitors, especially for more standard alloys. Some customers also have unique inventory-control needs, so we work with many customers to ship on-demand by retaining a buffer stock of spheres here at Indium.

Unique Sizes:

Our current dimensional capabilities as of this writing are from 80microns to 0.062inches, or even bigger. Generally, the bigger the sphere - the less spherical it is (within the limits of surface tension and viscosity), and we can't control the laws of physics, so instances where a very large amount of solder is needed, a preform may have better dimensional control. Also, notice that we won't ask that you order in a specific unit of diameter measurement, like the mil or the micron or the millimeter: we're a global company - just tell us what you need.

Unique Packaging:

Often needed for more delicate alloy spheres, we can offer specialty overpacking that eliminates oxides from the atmosphere around the solder spheres, essentially stopping oxidation in its tracks. It's the same technique we use to package our soft solder die-attach (SSDA) wire: a technique that showed that the very reactive wire was still "as new" 3 years later. We also offer spheres in tape & reel packaging (see image) for 24mil, 35mil and 62mil diameter spheres.

Unique Tolerances:

Just as a case in point, a MEMS customer of ours had a need for a low-melting indium-alloy solder sphere with a tolerance of +/-5microns (+/-0.005mm) for a sphere with a 350micron diameter. That demands a tolerance of just over 1% - pretty demanding, but we did it.

Our standard tolerance is +/-1mil (1 thousandth of an inch, or 25.4microns), but as you can see, we have the capability to go to much tighter tolerances using three proprietary manufacturing techniques.

Other Needs:

We are also seeing people asking for doped-alloy spheres; low-alpha emission solder spheres and other things that we could never have dreamed of...

So please just let us know what you need. We'd be happy to help out, and if we can not do what you ask - we'll let you know why.

Cheers!  Andy

Shelf life means different things in different situations.  Post something on the internet and it will last forever.  Leave fresh fruit out on a hot day and it won't make it through the afternoon.

Jim Hisert recently wrote a blog post on Solder Shelf Life where he teams up with Eric Bastow to discuss Solder Shelf Life.  As they state, Solder Paste has a very defined shelf life because of the flux component.  The shelf life of Solder Preforms, on the other hand, is defined by the solder alloy's propensity to form oxides on the surface of the metal.

How do you minimize Solder Shelf Life issues?  There are several ways:

1) Order quantities that are reflective of your usage. It is attractive to get a large-volume price break, but you need to be able to use the product when the time comes.
2) Request that the solder preforms be packaged in quantities that you use them.  Getting a year's worth of preforms in one bottle may be cheaper, but the constant opening of the jar will only cause the remaining parts to oxidize and become unusable. If you consume 120,000 preforms per year, consider having your order shipped 10,000 pieces per month to assure a fresh supply of material.
3) Store preforms in their original, unopened containers, in a nitrogen dry box.
4) Once you have opened the jar, keep the lid on while it is at the work station.  At the end of the day, return the jar to the nitrogen dry box with the lid off so the nitrogen can purge the oxides that may have begun to form.
5) Consider tape & reel packaging.


 

There is nothing more frustrating than going through an entire process (whether it is putting together a puzzle or manufacturing a product) only to find the final piece missing. 

That final piece can be the strength of the solder joints which can impact the quality of your product or the amount of rework that needs to be done.  As the products get smaller and the solder paste stencils get thinner, the ability to get enough solder paste to adequately hold shields, components and connectors gets harder and harder.

So what is that final piece of the puzzle?  Consider Solder Fortification® Preforms.  These are solder preforms, which are solid pieces of solder, that are added to a solder paste deposit to give it the additional volume required to create a stronger joint.  They generally come in sizes similar to components, such as 0402 and 0603, and are packaged in tape & reel like the components so they are easily placed with standard pick and place equipment.

The additional solder can improve your first past yields and reduce field failures.  Now that is the perfect final piece to complete the picture!

Considering a fusible alloy as a solution really starts with the applications temperature profile. When cooking a turkey (pop-up timer) or supressing a fire (sprinkler systems), its all about the heat and what the fusible alloy does in response to it.  Reliability is achieved through ensuring that each alloy is homogenious and not subjected to segregation. Take a look at our list of alloys, and you'll find that there are many options to choose from, many of which are Bismuth containing. These can be manufactured in many shapes and sizes and due to the high volume nature of these applications, the need for tape and reel is almost a given.
 

Tape and Reel

Tape and Reel has been on my mind a lot lately. Staying on top of this preform packaging trend is important.

Whether we're looking for the right size pocket, cover tape, or even the orientation of the part, the name of the game is always performance. If the peel force isn't within a tight spec or the pocket is too large, then a drop in pick performance is imminent. Everyday there is a new challenge and new part someone wants placed in tape. Just when we think we've seen it all, a customer will come to us for help on something new.

Were always looking for new challenges, so feel free to contact me with yours.  

 

Seth Homer is a Product Support Specialist for Engineered Solder Materials.  He’s like a Green Beret or Navy Seal of solder preforms.  He is another contact here at Indium that you can use to make your soldering application more successful and efficient.

You can read more about Seth here: http://www.indium.com/people/biographies/seth-homer/.

Here’s what he has to say about preforms for die attach applications…

Jim:  You have a trained eye for solder preform applications, how often do you see opportunities where a customer can improve their process by using a different form of solder?

Seth:  Although my world is engineered solders, and I am somewhat bias, I have yet to visit a customer who has no interest or need for a preform. The advantages are many….

Repeatability in solder volume

Repeatability in flux percentage in situations where flux is required

Ease of placement where automation is a possibility (Tape and Reel or Waffle pack)

In situations where paste is the current process, switching to a preform offers a stronger joint, a cleaner joint (less flux), and less voiding due to flux residue.

In situations where a solder joint needs to be fortified, a small preform added to the paste offers increased reliability (Solder Fortification®)

Jim:  Strong, clean, void free solder joints are especially important for high power die attach applications.  Aside from equipment changes, what can customers expect if they change over to a preform application from a paste application?

Seth: That would depend on a lot of things; in all honesty there are some applications where paste is the best option.  [Like a drop-in replacement for polymer die attach materials, die attach paste utilizes the same equipment set.]  Any process/application change will demand optimization, but once those variables are addressed, I think most of our customers will see yield increases as well as reliability increases.

Jim: One important concern for an engineer switching from a dispensed material to a solid (preform) material is packaging and presentation to die-attach equipment.  Can you give me a rundown of packaging options for solder preforms for HVM production and prototyping?

Seth: In HVM situations, automated placement is a must. We have two primary options for HVM packaging for an automated process. Tape and reel, or waffle pack. Tape and reel offers high speed placement, flexibility, high volume packaging on a compact reel, and an environment which prohibits damage to individual parts. Waffle pack offers many of the same benefits of tape, but lends itself better to manual placement if an automated process is not needed.

Jim:  If our readers are interested, what is the best way to get started evaluating preforms?

Seth: The best way to begin is to define what you want to achieve, and then bring your request to me or one of our application engineers. This gives us an opportunity to understand what you’re trying to achieve, and make suggestions to help if needed. This will make the transition to an engineered solder much smoother, and rewarding.

Seth can be reached at shomer@indium.com