TIM Fluxes

Rosin/Resin Based Liquid Soldering Fluxes

Flux	#5R	#5RMA	#5RA
Rosin/Resin Bas	Heat Stabilized Resin	Heat Stabilized Resin	Heat Stabilized Resin
Soldering Temperature Range	125ºC - 350ºC	125ºC - 350ºC	125ºC - 350ºC
Metallization To Be Soldered	Au, Ag, Pt, Pd, Clean Cu	Au, Ag, Pt, Pd, Clean Cu, Sn, Solder Plate	Ni, Rh, Cd, Brass, Bronze, BeCu, Pb, Oxidized Cu
Activation	None Added	Mildly Activated	Fully Activated
Solids Content	47%	46%	44%
Water Resistivity Extract (ohm-cm)	>100,000	>100,000	>50,000
Specific Gravity	.90	.91	.88
Boiling Point	84ºC	84ºC	84ºC
Flash Point	11ºC	11ºC	11ºC
IPN	84072	84032	84039
Thinner	#8300 (Part Number 84041) - all fluxes

Flux Removal

Since the post solder residues of types R and RMA fluxes are considered non-corrosive, non-conductive and non-hydroscopic, flux removal is not usually necessary. If cleaning is desired this is best accomplished with a commercially available flux residue remover.

Best practice is to always remove RA residues in electronics applications.

Standard Packaging

These liquid soldering fluxes are packaged in 2 different size plastic containers:

• 1 U.S. pint (0.473 liter)
• 1 U.S. gallon (3.785 liter)

NC-506 Flux

Features

• Suitable for Pin-Grid Array and standard Ball Grid Array applications
• Excellent solderability to all common surface metallizations
• No-clean residue
• Can be used for printing, dipping, and pin transfer deposition
• Offers high yields in BGA bumping process
• Suitable for both Pb-Free or Sn/Pb applications

Introduction

Ball Attach Flux NC-506 is a low viscosity thixotropic no-clean flux designed for use in ball attachment to substrates (BGA manufacturing). It is especially useful in applications requiring soldering to surface finishes with tenacious oxides, such as nickel. It can also be used wherever a no-clean ball attach flux is needed, and is suitable for a variety of different deposition methods.

Properties

	Value	Test Method
Flux type Classification:	ROL1	J-STD-004 (IPC-TM-650: 2.3.32 and 2.3.33)
Typical Viscosity:	320kcps	Brookfield HB DVII+ -CP (5rpm)
SIR (ohms, post cleaning):	Pass (>109 after 7 days @ 85ºC & 85% RH)	J-STD-004 (IPC-TM-650: 2.6.3.3 IPC-B-24
Typical Acid Value:	103mg KOH/g	Titration
Typical Tack Strength:	250g	J-STD-005 (IPC-TM-650: 2.4.44)
Shelf Life:	6 months (-20°C to +5°C)*	Viscosity change / microscope examination

All information is for reference only. Not to be used as incoming product specifications.

WS-366 Interconnect Flux

Benefits

• Excellent cleanability, residue can be removed with room temperature water
• Can be used for printing, dipping, and pin transfer deposition
• Offers high yields in BGA bumping process
• Excellent solderability
• Wide process window
• Suitable for Sn/Pb, Pb-Free, and high lead-containing applications
• Designed for Flip-Chip applications

Introduction

WS-366 Interconnect Flux is a high viscosity paste-type flux designed for use in BGA bumping and board level attachment. It can also be used wherever a water-soluble flux with excellent cleanability is desired.

Properties

Flux type Classification:	H1
Color:	Amber to brown
Stencil Life:	>8 hours at room temperature
Shelf Life:	3 months at 0 to +30 °C
SIR (ohms, post cleaning):	Pass (>109 after 7 days @ 85ºC & 85% RH)
Typical Viscosity:
Brookfield:	425kcps at 5rpm
Halide Content:	<3% Cl equivalent
Acid Value:	30-50
Tack Strength:	100-400g

All information is for reference only. Not to be used as incoming product specifications.

Fluxless Soldering

Some applications are very sensitive to the use of a flux due to the post reflow residue that may be present. Also, flux may be a problem in a vacuum environment or in an application in which it must be free of corrosive or volatile materials.

If gold is used for the outer metalization on the parts to be joined, acceptable wetting may be possible without the use of a flux. If this is not possible, a reducing atmosphere may be used to remove the oxides and result in sufficient wetting. Below are suggestions and helpful hints for choosing a reducing atmosphere that fits your application.

• Common reducing atmospheres are:
  88% nitrogen, 12% hydrogen
  90% nitrogen, 10% hydrogen
  95% nitrogen, 5% hydrogen
  100% hydrogen
• The higher the reflow temperature the more effective the oxidation removal using a reducing atmosphere. A reflow temperature that is 350°C and above is the best for oxide removal.
• Nitrogen or argon is sometimes used in fluxless soldering because it prevents the formation of oxides during reflow. However, these gases do not remove preexisting oxides on the metalization, only the hydrogen can do that.

Fluxless soldering is also used when joining the two substrates together where flux residue would be detrimental to the operation of the final product. For example, voiding due to flux entrapment can result in poor performance because of reduded electrical or thermal conductivity.

In an application where a reducing atmosphere is not practical, two or more metalizations can be joined using flux in the initial pre-coating of the substrates. After precoating is complete, the flux residue can be removed using an appropriate solvent. The cleaned parts can then be assembled without a flux and reflowed a final time to join them. This method is especially effective when fairly large pieces need to be joined and flux entrapment can not be tolerated.