LOCTITE ABLESTIK ABP 8068TA

Harmonization Code : 3506.91.90.99 | Prepared glues and other prepared adhesives, not elsewhere specified or included; products suitable for use as glues or adhesives, put up for retail sale as glues or adhesives, not exceeding a net weight of 1 kg ; Adhesives based on polymers of headings 3901 to 3913 or on rubber; Other ; Other

Main features

Excellent workability
Dispensable
Printable

Product Description

LOCTITE ABLESTIK ABP 8068TA is a semi-sintering die attach adhesive designed for semiconductor packages requiring high thermal and electrical conductivity. This material’s epoxy assisted sintering formulation is designed to provide high adhesion, high thermal and low stress properties which are essential for thermal and reliability performances of high end power packages. .

LOCTITE ABLESTIK ABP 8068TA has a thermal performance that is comparable to a solder paste material. In conventional box oven curing, it will cure at 1 hour at 200ºC or 175ºC. This silver filled conductive adhesive is printable and dispensable with excellent workability. It offers good sintering properties when used on Ag, PPF, Au and Cu substrates with a high thermal stability. Its high reliability make it a good solder replacement candidate and is typically used for packages such as QFN, LGA and HBLED.

Specifications
Additional Information

Technical Specifications

General Properties

Shelf Life Shelf Life Shelf life is the amount of time after manufacturing that a product is guaranteed to retain its properties. It differs vastly per product and it is based on temperature and storage conditions. The properties can be guaranteed for the temperature and time range indicated on the TDS since those are the ones tested to be the best for the product.
Shelf Life @ -40°C	365 days

Work life @25°C

Work life @25°C
Work life is the amount of time we have to work with a material until it is no longer able to be easily worked and applied on a substrate.

It is based on the change in viscosity and it can rely on the application requirements.

24 hours

Physical Properties

Thixotropic index

Thixotropic index
Thixotropic Index is a ratio of a material s viscosity at two different speeds in Ambient temperature, generally different by a factor of ten.

A thixotropic material s viscosity will decrease as agitation or pressure is increased. It indicates the capability of a material to hold its shape. Mayonnaise is a great example of this. It holds its shape very well, but when a shear stress is applied, the material easily spreads.

It helps in choosing a material in accordance to the application, dispense method and viscosity of a material.

Viscosity

Viscosity
Viscosity is a measurement of a fluid’s resistance to flow.

Viscosity is commonly measured in centiPoise (cP). One cP is defined as
the viscosity of water and all other viscosities are derived from this base. MPa is another common unit with a 1:1 conversion to cP.

A product like honey would have a much higher viscosity -around 10,000 cPs-
compared to water. As a result, honey would flow much slower out of a tipped glass than
water would.

The viscosity of a material can be decreased with an increase in temperature in
order to better suit an application

9,000 mPa.s

Chemical Properties

Ionic Content
Chloride (Cl-) Chloride (Cl-) The amount of Chloride (Cl-) ion extracted from the product in parts per million (ppm)	35 ppm
Potassium (K+) Potassium (K+) The amount of Potassium (K+) ion extracted from the product in parts per million (ppm)	3 ppm
Sodium (Na+) Sodium (Na+) The amount of Sodium (Na+) ion extracted from the product in parts per million (ppm)	3 ppm

Moisture absorption

0.26 %

Mechanical Properties

Shear strength
Shear Strength @250°C	17.8 N/mm2

Tensile Modulus Tensile Modulus Tensile modulus is a mechanical property that measures the stiffness of an elastic material. It is the slope of stress / strain curve of a material under direct tensile loading. It can be used to predict the elongation or elastic deformation of an object as long as the stress is less than the tensile strength of the material. Elastic deformation is caused by stretching the bonds between atoms and the deformation can be reversed when the load is removed. Tensile modulus is affected by temperature and is an important engineering attribute since we generally want to keep elastic deformation as small as possible.
Tensile Modulus @-65°C	15,800 N/mm2
Tensile Modulus @150°C	2,100 N/mm2
Tensile Modulus @25°C	11,800 N/mm2
Tensile Modulus @250°C	1,500 N/mm2

Thermal Properties

Coefficient of Thermal Expansion (CTE)

Coefficient of Thermal Expansion (CTE)
CTE (Coefficient of thermal expansion) is a material property that is indicative of the extent to which a material expands with a change in temperature. This can be a change in length, area or volume, depending on the material.

Knowing the CTE of the layers is helpful in analyzing stresses that might occur when a
system consists of an adhesive plus some other solid component.

Coefficient of Thermal Expansion (CTE), α1

Coefficient of Thermal Expansion (CTE), α1
CTE α1 (alpha 1) is the slope of the Coefficient of thermal expansion in a temperature range below the Glass transition temperature (Tg).

It explains how much a material will expand until it reaches Tg.

54 ppm/°C

Thermal Conductivity

Thermal Conductivity
Thermal conductivity describes the ability of a material to conduct heat. It is required by power packages in order to dissipate heat and maintain stable electrical performance.

Thermal conductivity units are [W/(m K)] in the SI system and [Btu/(hr ft °F)] in the Imperial system.

110 W/m.K

Additional Information

How would this perform for GaN on SiC to Au plated Cu?

Silicon Nitride is an alternative to Silicon. The wafer / chip is normally fabricated from Silicon Nitride. This is mechanically fairly similar to silicon (it’s a bit harder & more brittle), so die attach that works with silicon is typically good on SiN.

GaN (Gallium Nitride) is a semiconductor layer that is grown on top of a silicon or SiN wafer / chip surface. So for die attach it is similar to attaching a Si or SiN chip.

8068TA is a “semi-sinter” material. It needs a layer of Ag or Au on both the chip & the substrate to give a good bond. An SiC wafer should have a metal back side metallization (BSM) like Ag or Au and this is the surface to sinter to. Bare Cu can also be OK for some “non-critical” applications, but it is not recommended.

Cure Schedule

For die size <5 x 5 mm