Gold Solder
Gold Alloy Solder Paste
Gold-tin solder paste is used in a variety of applications that require a melting temperature over 150°C, good thermal fatigue properties, and high-temperature strength. It is widely used in military, aerospace, high-power LED, and medical applications.
Powered by Indium Corporation
- Superior Thermal Conductivity
 - Good Joint Strength
 - Excellent Wetting Properties
 

Product Overview
Gold-Tin (AuSn) Alloy Solder Solutions
Indium Corporation offers a comprehensive range of gold-tin (AuSn) alloys, including:
- 80Au20Sn
 - 79Au21Sn
 - 78Au22Sn
 - 77Au23Sn
 
These alloys are ideal for high-reliability applications requiring excellent performance, thermal conductivity, and durability.
Particle Size & Metal Loading
Gold-tin solder paste is offered in powder sizes ranging from 2 to 7 C. Metal loadings vary between 91% to 94%, depending on the desired application method and particle size.
Flux Options for AuSn Solder Paste
Our gold-tin alloy solder paste is available with a variety of flux vehicles to meet specific application needs:
No-clean Flux:
- AuLTRA® 5.1 (used in high-power LED and MEMs applications)
 - AuLTRA® 5.1LS (utmost slump resistance)
 - Indium10.8HF (accommodates higher processing temperatures required by the electronics industry)
 - RMA-SMQ51A (for difficult to solder surfaces in die-attach)
 - NC-SMQ75 (halogen-free and low-residue; requires <10 ppm oxygen)
 
Water-wash Flux:
- AuLTRA® 3.2 (used in high-power LED applications)
 - Indium3.2HF
 
Packaging Options
Our gold-tin solder paste is available in convenient packaging options, including:
- 10cc and 30cc syringes for easy dispensing
 - Custom packaging available upon request
 
Product Data Sheets
AuLTRA® 3.2 AuSn Water-Soluble Solder Paste PDS 99986 (A4) R2.pdf
AuLTRA® 3.2 AuSn Water-Soluble Solder Paste PDS 99986 R2.pdf
AuLTRA® 5.1 AuSn No-Clean Solder Paste PDS 99987 (A4) R3.pdf
AuLTRA® 5.1 AuSn No-Clean Solder Paste PDS 99987 R3.pdf
Related Applications
Gold alloy solder pastes are available for use in a variety of applications.
Related Markets
Indium Corporation is a leading gold solder innovator that provides high-temperature, high-reliability, and critical applications such as die-attach and hermetic sealing to the following areas:
Expert Support for Reliable Results
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