3M

™ Thermally Conductive Adhesive Tapes 8940 / 8943

3/4

Thermal

Resistance

Properties

Test

Unit

Value

Test Method

Thermal Gravimetric Analysis *

Mass loss at 200 °C

%

< 0,2

Mass loss at 150 °C after 4 h

%

< 0,3

3M

Flame Class:

UL 94 V-0, File E253171, Flame rating applies to adhesive film (3M

conductive Tape 8940) bonded to 3.0 mm minimum thickness aluminium on one side and

0.86 mm minimum thickness FR-4 laminate on other side.

Application

Guidelines

1.) Substrate surfaces should be clean and dry prior to tape application. Isopropyl alcohol

(isopropanol) applied with a lint-free wipe or swab should be adequate for removing

surface contamination such as dust or finger prints. Do not use “denatured alcohol” or glass

cleaners which often contain oily components. Allow the surface to dry for several minutes

before applying the tape. More aggressive solvents (such as acetone, methyl ethyl ketone

(MEK) or heptane) may be required to remove heavier contamination (grease, machine oils,

solder flux, etc.) but should be followed by a final isopropanol wipe as described above.

Note: Be sure to read and follow the manufacturers’ precautions and directions when using

primers and solvents.

2) Apply the tape to one substrate at a modest angle with the use of a squeegee, rubber roller

pressure to help reduce the possibility of air entrapment under the tape during its

application. The liner can be removed after positioning the tape onto the first substrate.

3) Assemble the part by applying compression to the substrates to ensure a good wetting of

the substrate surfaces with the tape. Proper application of pressure (amount of pressure,

time applied, temperature applied) will depend upon design of the parts. The preferred pressure at

room temperature is a minimum of 1 kg/cm

needed.

Rigid substrates are more difficult to bond without air entrapment as most rigid parts are not flat.

Flexible substrates can be bonded to rigid or flexible parts with much less concern about air

entrapment because one of the flexible substrates can conform to the other substrate.

Shelf Life

Product shelf life is 2 years from date of manufacture when stored at room temperature

conditions 22°C and 50% r.h. in the products original packaging.