The SAC305 NL900 is no longer available. It has been replaced by the NL932

Product Description
The SAC305 NL900 no-clean solder paste is a modified rosin based lead-free paste, which allows a previously unseen level of repeatability and consistency. This paste offers an excellent open time, extended abandon time and good soldering activity with pin probable post soldering residues.

Attributes

Pin-Probable Residue

ROL0 to ANSI/J-STD-004

Enhanced activity for tough to solder boards and components

Excellent slump resistance

High speed stencil printing up to 100mm/sec

Excellent tack performance and printer open time

Extended “between-print” abandon time

Performance
The printing performance of solder paste depends in part on the metal content, and the solder particle size range. Increasing metal content reduces the tendency to slump and reduces the tack life of the paste, while the solder balling performance improves.

Refrigeration and storage
It is recommended to store the SAC305 NL900 lead-free solder paste at 5-10°C. The paste should be removed from cold storage a minimum of 8 hours in the unopened container prior to use. If the paste does not reach room temperature, it may stick to the stencil, not deposit onto the SMT pads, de-wet pads during reflow, outgas during reflow, or produce solder balls. Avoid direct sunlight.

Handling and shelf life
The optimum temperature and humidity for no-clean solder paste are 75°F and 60% or below respectively. Provided SAC305 NL900 is stored tightly sealed in the original container at 5-10°C, a minimum shelf life of 6 months can be expected. Air shipment is recommended to minimize the time that containers are exposed to higher temperatures.

Printing
The SAC305 NL900 lead-free no-clean solder paste is currently available for stencil printing down to 16 mil (0.4mm) pitch devices with type 3 powder (-325+500 mesh). Printing at up to 100 mm/sec. can be reliably achieved in production using a metal squeegee blade. This is due to a unique rheology, which ensures that the higher shear rate viscosity is relatively low and the thixotropic index is high enough to ensure excellent definition and slump resistance, while maintaining good roll and drop off behavior. High squeegee pressures are not required, making SAC305 NL900 particularly useful for second side printing processes.

Reflow
Reflow of this lead-free solder paste should be performed at 15-30°C above the liquid temperature of the alloy (depending on the type of board).

ALLOY	COMPOSITION	MELTING POINT (°C)
SN96CI	Sn/3.8Ag/1Cu	217
SN97C	Sn/3Ag/.5Cu	217-219

This temperature should be maintained for 30-60 seconds. Profiles should have less than a 3-minute preheat time above 260°F(130°C) to insure proper wetting of fine pitch leads.

REFLOW PROFILE
1. Ramp to 140-160 degrees Celsius at 2 degrees Celsius per second.
2. Hold at 150-180 degrees Celsius for 60-120 seconds.
3. Ramp to peak reflow at 2 degrees Celsius per second.
4. Recommended peak reflow temperature is 235-245 degrees Celsius.
5. Dwell above liquidus for 45-90 seconds.

Cleaning
If cleaning is required, use a semi-aqueous solvent or DI water with a saponifier such as Florida Cirtech RA2000 (saponifier concentration 4-6% @ 120-150°F).

Health & Safety
This product, during handling or use, may be hazardous to health or the environment. Read the Material Safety Data Sheet and warning label before using this product.

Packaging
The SAC305 NL900 lead-free no-clean solder paste is also available in: 500 gram or 250 gram plastic jar. 1 Kilogram, 500 gram or 250 gram cartridge for direct application. DEK ProFlow cassettes available upon request.