Koki no-clean LEAD FREE solder paste. High-reliability Low Ag Lead Free Solder Paste

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1 #514- Revised on Feb.4, 214 Koki no-clean LEAD FREE solder paste High-reliability Low Ag Lead Free Solder Paste S1XBIG58-M5-4 Product information S1XBIG SAC35 After -4/125ºC, 1 cycles This Product Information contains product performance assessed strictly according to our own test procedures and may not be compatible with results at end-users.

2 2 Product features Solder alloy composition is Sn.1Ag.7Cu 1.6Bi +Ni. HIGH RELIABILITY Low-Ag Alloy compared with conventional low-ag alloys PERFECT MELTING and wetting at super fine pitch micro components (>.25mm dia. CSP, 63 chip). Stable viscosity performance due to prevention with chemical reaction between solder powder and flux. Low solidus point (211ºC) may allow to apply the CONVENTIONAL reflow profile for SAC35. Conforms to HALOGEN FREE standard (Cl+Br = Less than 15ppm) BS EN14582.

3 3 Application Product Alloy Composition (%) Printing - Stencil S1XBIG58-M5-4 Sn.1Ag.7Cu 1.6Bi +Ni Alloy Flux Product Melting point (ºC) Shape Spherical Particle size (µm) 2-38 Halide Content (%) Flux Type ROL* 3 Flux Content (%) 11.2 ±1. Viscosity* 1 (Pa.s) 22 ± 3 Copper plate corrosion* 2 Passed Tack Time > 24 hours Shelf Life (-1ºC) Optional powder size (µm) 6 months 2 ~ 45: S1XBIG48-M5-4 *1. Viscosity : Malcom spiral type viscometer,pcu-25 at 25ºC 1rpm *2. Copper plate corrosion : In accordance with IPC J-STD-4A *3. Flux type : According to IPC J-STD-4A

4 4 Test condition Stencil :.12mm thickness, laser cut stencil Printer : Model YVP-Xg YAMAHA Motor Squeegee : Metal blade, Angle - 6º Print speed : 4 mm/sec Atmosphere : 24-26ºC (5-6%RH) Test pattern :.25 mm dia.,.4mmp QFP pattern 1st print 1th print After 2strokes 1th print.25mmdia..4mmp QFP Consistent and quality printability over the continual prints.

5 Viscosity (Pa.s) S1XBIG58-M5-4 5 Test condition Print (knead) solder paste on the sealed-up stencil continually up for 24 hours to observe viscosity variation. Squeegee : Metal blade, Angle - 6º Squeegee speed : 3mm/sec. Print stroke : 3mm Printing environment : 24-26ºC, 4-6%RH S1XBIG58-M5-4 5 *12 strokes/hour No. of print strokes (times) A newly developed flux formula has succeeded to realize consistent long term printability by preventing excessive viscosity drop due to shear thinning and excessive increase due to chemical reaction between solder powder and flux medium during the repeated rolling.

6 Temp. (ºC) S1XBIG58-M5-4 6 Test condition.25mm dia. Material : Surface treatment : Stencil thickness : Pad size : Component: Stencil aperture : Heat source : Atmosphere : Reflow profile : Glass epoxy FR-4 OSP, NiAu.12mm (laser cut).25mm dia. 63R (21) chip, 1%Sn 1% aperture opening to pad Hot air convection Air See below.25mm dia. 63R(21) 3 63R(21) chip OSP NiAu Time(s) Larger relative surface areas of solder paste exposed due to miniaturization of components (CSP, 63 chips), often causes incomplete coalescence of the solder due to excessive oxidation during the reflow. An improved flux formula ensures complete coalescence by minimum deterioration of barrier performances.

7 7 test Test condition Material : Glass epoxy FR-4 Surface treatment : OSP Stencil thickness :.12mm (laser cut) Pad size :.8 x.8mm diameter Component:.76mm ball SAC35 Stencil aperture : 1% aperture opening to pad area Heat source : Solder pod 275ºC Mount interval: 1sec. Pillow defect S1XBIG58- M5-4 Drop a solder ball every 1 sec. after the solder paste has melted to see the heat durability of flux. 3sec 4sec 5sec Good NG Conventional solder paste M5-4 retained the activation even up to 5sec. and allowed the complete merger of the solder bump with the molten solder, while the conventional solder paste resulted in the partial merger only 3sec. after the solder paste has melted. The results demonstrates that M5-4 shall effectively prevent the occurrence of head-in-pillow defect.

8 8 Test condition Material : Surface treatment : Stencil thickness : Stencil aperture : Components Heat source : Atmosphere : Reflow profile : Glass epoxy FR-4 OSP, NiAu.12mm (laser cut) 1% aperture opening to pad area Pwtr, 633R(2512) -1% Sn BGA ball - SAC35 Hot air convection Air Same as 633R BGA Pwtr Pwtr. 633R(2512) BGA OSP NiAu M5-4 ensures low voiding regardless of the type and size of the components.

9 9 Test condition * BS EN14582 Elements Results F Not detected Cl Not detected Br Not detected (ppm) Conforms to Halogen-free standard (Cl+Br: less than 15ppm) BS EN14582.

10 1 Item Result Method Tack time > 24 hours JIS Z 3284 Heat slump.3mm pass JIS Z 3284 Solder balling < Category 3 JIS Z 3284 Copper mirror corrosion Type L IPC J-STD-4A Copper plate corrosion Pass IPC J-STD-4A JIS Z 3284 Voltage applied SIR > 1E+9 IPC J-STD-4A JIS Z 3284

11 Joint strength (N) S1XBIG58-M Thermal cycling test; Share strength Thermal cycling conditions : -4/+125ºC, 6min./cycle x 1cycles Testing machine : SEISIN SS3WD Thermal cycle conditions; -4/125 SAC35 S1XBIG Test board & components 3216R (3pcs) 212R (3pcs) 168R (3pcs) 15R (3pcs) 63R (3pcs) PCB: FR4 Surface finish: OSP Cu thickness : 18μm PCB thickness : 1.6mm 75 Pad size R A R 168R C B (mm) A B C 3216R R Chip 212R Chip 168R Chip No of cycle 15R Chip 63R Chip 15R 63R 212R R R R S1XBIG solder alloy exhibits higher shear strength than SAC35, especially with relative large components due to solid solution effect of Bi containing alloy.

12 12 Thermal cycling test; Cross-sectional observation T/C condition Alloy SAC35 S1XBIG Before 3216R Chip -4/+125ºC 5cycles Cracking 1cycles No cracking or rupture occurred in the solder fillets formed by S1XBIG, while SAC35 solder fillets show some cracking after 1 cycles.

13 13 1. Printing 1) Recommended printing parameters (1) Squeegee 1. Kind : Flat 2. Material : Rubber or metal blade 3. Angle : 6º (rubber) or metal blade 4. Pressure : Lowest 5. Squeegee speed : 2~1mm/sec. (2) Stencil 1. Thickness : 15~1 m for.65~.4mm pitch pattern 2. Type : : Laser or electroform 3. Separation speed : 7.~1.mm/sec. 4. Snap-off distance : mm (3) Ambiance 1. Temperature : 23~27ºC 2. Humidity : 4~6%RH 3. Air draft : Air draft in the printer badly affects stencil life and tack performance of solder pastes. 2. Shelf life ~1ºC : 6 months from manufacturing date * Manufacturing date can be obtained from the lot number ex. Lot No No. of lot : 2nd Date : 4th Month : Feb Year : 214

14 14 Recommended reflow profile (ºC) Peak temp. 235~25ºC Pre-heat temp. 15~19ºC 6~1sec. 15 Over 227ºC >3 sec Ramp-up temp. 1.~3.ºC/sec. 12 (sec.) Pre-heat conditions Target : 15~18ºC 1sec Upper limit: 18~19ºC 1sec Lower limit: 15~175ºC 6sec 18 24

15 15 Recommended reflow profile (ºC) 25 2 Higher pre-heating temperature may lead to grainy solder fillet or de-wetting by accelerating oxidization of the solder alloy and exhaustion of the flux activation. It is recommended to decrease pre-heating temperature in case poor solder wetting is observed. Shorter TAL and lower peak temperature may become a cause of voiding. In case relatively larger volume of voiding is observed, it is recommended either to increase the peak temperature or extend TAL (for >45sec.) Fast ramp-up speed is prone to cause bridging, mid-chip balling or solder beading by promoting heat slumping. It is recommended to slow down ramp-up temperature to alleviate the degree of heat slump of the solder paste. Similarly to the pre-heating, slow temperature elevation between preheating to the peak is prone to cause grainy solder fillet and/or de-wetting to the pad due to excessive oxidization of the solder alloy, pad surface and exhaustion of the flux activation. It is recommended to quicken temperature elevation speed in case the poor solder wetting is observed (sec.) 18 24