Related Die-Attach Blog Articles
What the Off-Eutectic?
Indium Corporation's new off-eutectic alloy preforms ensure strong solder joints in a plethora of device and package hardware. Our off-eutectic AuSn preforms are currently available now in 79/21, 78/22, and 75/25 compositions, with a wide range of X, Y, and Z dimensions available.
Read MoreIMS 2020 Virtual Show
The International Microwave Symposium (IMS) Live Stream Event (Aug 4-6) is the premier annual international meeting for technologists involved in all aspects of microwave theory and practice. It consists of a full week of events, including technical paper presentations, workshops, and tutorials, as well as numerous social events and networking opportunities.
Read MoreThat's a 'Fine' Ribbon You Got There!
Indium Corporation has developed 80Au20Sn < 0.1” wide fine-grade precision ribbon for high volume, fully automated laser diode assembly processes. Our high quality precision AuLTRA™ Fine Ribbon is designed for high volume production and is packaged on precision spools suitable for auto-feed systems.
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Die-Attach Wire
Indium Corporation's Die-Attach Wire (or SSDA [soft solder die-attach] wire) is a fluxless solder wire used to effect die-attach. SSDA grade wire will result in higher yields of an improved quality product with fewer interruptions in production.
Key Performance Needs
- Ultralow oxide (wire surface and in wire)
- High alloy purity
- Precise and consistent wire diameter
- Tight alloy chemistry control


Die-Attach Paste
Although there are four major processes for die-attach, solder-based processes are still the most popular, as they provide high reliability with ease of processing. Indium Corporation’s die-attach solder paste is typically a dispensable, high melting-point solder paste, which is reflowed in forming gas (H2N2 mix).
Key Performance Needs
- Low voiding in reflow
- Long dispense life
- No tailing
- No separation
- Bubble-free packaging
- Residue-free cleaning or residue compatible with overmolding process

“Power-Safe” NC-SMQ®75 Die-Attach Solder Paste
NC-SMQ®75 is the only solder paste suitable for use in non-cleaned clip-bonded applications in power semiconductor die-attach assemblies. It has:
- Superior wetting capabilities compared to most low residue formulations
- Trouble-free probe testing
- No-residue appearance
BiAgX®75 Solder Paste
BiAgX®75 is a high-melting, lead-free solder paste technology that serves as a drop-in replacement for the high-Pb solder pastes used in many high-reliability, die-attach, and electronics assembly applications.
“Power-Safe” NC-SMQ75 Die-Attach Solder Paste
Indium Corporation’s “Power-Safe” NC-SMQ75 is an ultra-low residue, halogen-free, die-attach solder paste that leaves a completely benign, almost undetectable residue of approximately 0.4 weight percent of paste.
Alloy | Metal Content | Mesh Size | Particle Size | Recommended Needle Size* |
---|---|---|---|---|
Sn10/Pb88/Ag2 Sn5/Pb92.5/Ag2.5 Sn5/Pb95 Sn5/Pb85/Sb10 |
88% | Type 3 | 25 to 45 microns (Type 3) |
20 gauge* |
NC-SMQ75 is the only solder paste suitable for use in non-cleaned clip bonded applications in power semiconductor die-attach assemblies.
It is designed for reflow in a nitrogen or forming gas atmosphere of 100 ppm oxygen or less and can survive the high temperatures associated with both high-lead (Pb) and gold-tin alloy reflow.
Bellcore and J-STD Tests & Results
Test | Result |
---|---|
J-STD-004 (IPC-TM-650) | |
Flux Type Classification | ORL0 |
Presence of Halide Fluoride Spot Test |
Pass |
Elemental Analysis | Halide-Free |
Post Reflow Flux Residue (ICA Test) |
0.4% of solder paste |
Corrosion | Pass |
SIR (Post Clean) | Pass |
Acid Value (Typical) | 31.5 |
Test | Result |
---|---|
J-STD-005 (IPC-TM-650) | |
Typical Solder Paste Viscosity (Pb92.5/Sn5/Ag2.5. Type 3. 88%) |
|
Brookfield (TF 5 rpm) | 230 kcps |
Brookfield (R7 10 rpm) | 170 kcps |
Slump Test | Pass |
Solder Ball Test | Pass |
Wetting Test | Pass |
Standard Metal Load | 88% |
All information is for reference only. Not to be used as incoming product specifications.
Features:
- Ultra-low post-reflow residue <0.5%w/w of solder paste
- “Power-Safe” residue compatible with overmolding compounds without delamination
- Halogen-free
- Consistent dispensing deposit size without clogging (Powder types 3, 4, 5, 6)
- Airlessly syringe-packed (bubble-free)
- Wide range of alloy compatibility
- Reflow up to 400°C
- Low oxygen or forming gas needed (<100ppmO2)
- Low-voiding for smaller die (< 6mm x 6mm)
- Meets <5% single, <10% total industry voiding standard
- Good wetting with common metal finishes
