• High oxidation barrier to eliminate graping and HIP defects
• Highly probe testable flux residue
• Halogen-free per EN14582 test method
• Excellent print transfer efficiency on 0.4mm pitch CSP's
Indium8.9HF-1 is an air reflow, no-clean solder paste. Indium8.9HF-1 offers unprecedented stencil print transfer efficiency to work in the broadest range of processes. In addition, the high probe testability of Indium8.9HF-1 minimizes false failures in ICT.
Indium Corporation manufactures low-oxide spherical powder composed of a variety of Pb-Free alloys that cover a broad range of melting temperatures. Type 4 and Type 3 powder are standard offerings with SAC and Sn/Pb alloys. The metal percent is the weight percent of the solder powder in the solder paste and is dependant upon the powder type and application. Standard product offerings are detailed in the following table.
Standard Product Specifications
Indium8.9HF-1 is currently available in 500g jars or 600g car tridges. Packaging for enclosed print head systems is also readily available. Alternate packaging options may be available upon request.
Storage and Handling Procedures
The shelf life of Indium8.9HF-1 is 6 months when stored at <10°C. Solder paste packaged in car tridges 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 two hours before use. Actual time to reach thermal equilibrium will var y with container size. Paste temperature should be verified before use. Jars and car tridges should be labeled with date and time of opening.
BELLCORE AND J-STD TESTS & RESU LTS
• Flux Type Classification - ROL0
• EN14582 Halogen Content -
• Corrosion - Pass
• SIR (IPC-J-STD-004B) - Pass
• SIR (IPC-J-STD-004A) - Pass
• Electromigration (IPC-J-STD-004B) - Pass
• Copper Mirror (JIS Z 3197) - Pass
• Malcom Solder Paste Viscosity (10rpm) - 1300 poise (typical)
• Tack Strength - 40g (typical)
• Solder Ball Test - Pass
• Wetting Test - Pass
• Slump Test - Pass
JIS Z 3197
• Copper Mirror - Pass
• Copper Plate Corrosion - Pass
Electroformed and laser cut/electropolished stencils
Recommended Profile (Pb-Free):
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 of stencil aperture has significantly reduced or eliminated the occurrence of mid-chip solder beads. The “home plate” design is a common method for achieving this reduction.
- Fine pitch components — A sur face area reduction is recommended for apertures of 20 mil pitch and finer.
This reduction will help minimize solder balling and bridging that can lead to electrical shor ts. The amount of reduction necessar y is process dependent (5-15% is common).
• For optimum transfer efficiency and release of the solder paste from the stencil apertures, industry standard aperture and aspect ratios should be adhered to.
The following are general recommendations for stencil printer optimization. Adjustments may be necessar y based on specific process requirement:
• Solder Paste Bead Size: 20-25mm diameter
• Print Speed: 25-100mm/sec
• Squeegee Pressure: 0.018-0.027kg/mm of blade length
• Underside Stencil Wipe: Star t at once ever y 5 prints then decrease frequency until an optimum value is determined.
• Solder Paste Stencil Life: >8 hrs. @ 30-60% RH& 22°-28°C
Indium8.9HF-1 is designed for no-clean applications, however the flux can be removed if necessar y by using a commercially available flux residue remover.
Stencil Cleaning is best per formed using isopropyl alcohol (IPA) as a solvent. Most commercially available stencil cleaners work well.
• Rework Flux: TACFlux® 089HF
• Cored Wire: CW-802, CW-807
• Wave Flux: WF-7742, WF-9945
The stated profile recommendations apply to most Pb-Free alloys in the Sn/Ag/Cu (SAC) alloy system, including SAC 305 (96.5Sn/3.0Ag/0.5Cu). For the SnPb profile and guidelines, contact Indium Corporation at firstname.lastname@example.org. This can be used as a general guideline in establishing a reflow profile when using Indium8.9HF-1 Solder Paste. Deviations from these recommendations are acceptable, and may be necessar y, based on specific process requirements, including board size, thickness & density.
The use of a linear ramp rate or ramp-to-spike (RTS) type profile assists in minimizing the greatest overall number of defects associated with the reflow process. If the ramp rate is too fast, it can cause solder balling, solder beading, and aggravated hot slump which can lead to bridging. The ramp rate in the preheat stage of the profile can range from 0.5°2.5°C/second (0.5°-1°C/second is ideal). A short soak of 20-30 seconds just below the melting point of the solder alloy can help minimize tombstoning when using a RTS type profile. If necessar y, a ramp-soak-spike (RSS) profile can be implemented to minimize voiding on BGA and CSP type packages. A soak zone between 150°- 200°C is acceptable.
To achieve acceptable wetting and form a quality solder joint, the acceptable temperature range above the melting point of the solder alloy is 12°-50°C (15°-30°C is ideal). The acceptable range for time above liquidus (TAL) is 30-100 seconds (45-60 seconds is ideal). A peak temperature and TAL above these recommendations
can result in excessive intermetallic formation that can decrease solder joint reliability.
A rapid cool down is desired to form a fine grain structure. Slow cooling will form a large grain structure, which typically exhibits poor fatigue resistance. The acceptable cooling range is 0.5°C-6.0°C/second (2.0°-6.0°C/second is ideal).
This product data sheet is provided for general information only. It is not intended, and shall not be construed, to warrant or guarantee the performance of the
products described which are sold subject exclusively to written warranties and limitations thereon included in product packaging and invoices.