NL932 No Clean Solder Paste
Download the TDS and MSDS for this product.
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INTRODUCTION |
| NL932 is a halide-free lead-free no clean solder paste, which allows a previously unseen level of repeatability and consistency. NL932, combined with FCT Assembly’s UltraSlic™ and Slic stencil, delivers Surface Area Ratio (SAR) paste transfer efficiencies below 0.6 and 0.55 respectively. NL932 is formulated to deliver exceptional cosmetics, especially when used in conjunction with Nihon Superior’s SN100C patented lead free alloy. NL932 can also be washed off in water under certain conditions. |
| ATTRIBUTES |
TEST RESULTS |
- Excellent print consistency with Surface Area Ratios (SAR) as low as 0.55 when used with the UltraSlic™ stencil technology
- Wide reflow profile window with good solderability on various
PCB surface finishes
- Completely Halide free by all tests (i.e., no hidden halides)
- Excellent cosmetics and a clear residue
- Water washable under certain conditions
- Low voiding/high reliability
- Compatible in either Nitrogen or Air reflow
- Formulated to work with SAC and SN100C alloys
| Alloy |
Metal Loading |
| SAC 305 |
88.50% for Type 3 |
| SAC 305 |
88.25% for Type 4 |
| SN100C |
88.50% for Type 3 |
| SN100C |
88.25% for Type 4 |
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| J-STD-004 (IPC TM-650) Test |
Result |
| Flux Type (per J-STD-004) |
ROL0 |
| Copper Mirror |
Pass |
| Halide Test |
Pass |
| Silver Chromate |
Zero |
| Fluoride Test |
Zero |
| SIR |
Pass |
| Ion Chromotography |
Zero |
| J-STD-005 (IPC TM-650) Test |
Result |
| Brookfield Viscosity Type 3 |
750,000 |
| Brookfield viscosity Type 4 |
800,000 |
| Slump |
Pass |
| Solder Ball |
Pass |
| Wetting |
Pass |
| Bellcore Test |
Result |
| SIR |
Pass |
| Electromigration |
Pass |
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| COOLING |
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A cooling rate greater than 2oC
per second should be used to insure a fine grain solder structure and
minimal IMC layer. |
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HEATING |
HEATING |
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A linear ramp of 0.5
to 2 C/sec is suggested to gradually remove the solvents and other
volatile components in the solder paste. This also helps in minimizing
solder balls, beading and bridging from hot slump.
A linear ramp also helps minimize depletion of flux activity
which can happen at extended times above the liquidus (TAL) and at very
high reflow temperatures.
A profile with a soak between 200-210C for less than 20 seconds
can be used to reduce void formation on BGA and CSP devices.
A short 20-30 second soak below the melting point of the solder can be
used to help minimize tombstoning. |
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PRINTING |
RECOMMENDED REFLOW PROFILE |
Fine Line Stencil’s Slic and
UltraSlic™ stencils are recommended for best printing characteristics
among stencil types. Below are surface area ratios achieved:
Slic ≤ 0.6 UltraSlic™ ≤ 0.55
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The recommendations apply to most lead free alloys in the SAC alloy system. This can be used as a general guideline in establishing a reflow profile when using NL932. Deviations from these recommendations are acceptable and may be necessary, based on specific process requirements including board size, thickness and other process characteristics. Please add 7-10C when using Sn100 based solder paste. |
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PRINTER OPERATION |
REFLOW |
The following are general
recommendations for stencil printer optimization. Adjustments may be
necessary based on specific process requirements.
| Application |
Recommendation |
| Solder Paste Bead |
2cm. Add when bead < 1 cm |
| Squeegee |
Metal, Slic blade preferred. 60 degrees from
horizontal |
| Speed |
25 to 150 mm/sec. |
| Pressure |
0.18-0.27 Kg/cm (squeegee length) |
| Underside Wipe |
Slic and Ultraslic should exceed > 10
prints/wipe
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| Stencil Life |
> 8 hours at 30+60% RH and 20-25˚C
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A peak temperature of 12-45 C above the melting point of the alloy is recommended for optimum results. A time above liquidus (TAL) of 30 to 90 seconds should also be used. Excessive temperature or excessive TAL may result in excessive Intermetallic Compound (SnCu—IMC) formation, which can adversely affect solder joint and long term reliability. |
| STORAGE AND HANDLING |
| NL932 should be refrigerated at 0-10˚C to prolong shelf life. At this range the shelf life will exceed 9 months. Cartridges should be stored tip down. Paste can be stored up to two weeks at room temperature. When refrigerated, warm up paste container to room temperature for up to four hours. Paste must be at ≥ 19˚C before processing. Working range of NL932 is between 19-32˚C. |
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