Bond pull test

When tungsten is deposited by means of CVD there is almost no adhesion to dielectric materials like silicon dioxide and silicon nitride. To overcome this problem an adhesion promoting layer prior to the tungsten deposition is deposited. Sputtered films such as TiW and TiN have received the most attention [Ellwanger et al.7, Rana et al.8] and have proven to provide adequate adhesion. With respect to this it must be emphasized that macroscopic adhesion (Scotch tape test or bond pull test) in itself is not a valid proof of adhesion. The ultimate evidence can only be obtained when... 

After a dwell time of five seconds under the device, it can be seen in Figure 7.10 that the shear strength of the bond between the LPDE sample and cyanoacrylate adhesive increased 10-fold, and the shear strength of the bond between the LPDE sample and the light cure acrylic adhesive increased 40-fold. Subsequently, MIL-STD-883 Method 2011.7 was applied as a destructive bond pull test to evaluate bond strength and bond strength distribution of various surface contaminations after CO2 treatment. The apparatus used had an accuracy of 5% and performed at a 90° peel angle. 

For Class K (space-grade), the additional tests of nondestructive wire bond pull, FIND, and radiography are imposed. Screen tests assure the reliability of the entire electronic product of which the adhesive joints are a part. 

For Class K (space-grade), the additional tests ofnondestmctive wire bond pull, FIND, and radiography are imposed. 

Tensile strength, Tensile strength is evaluated by pull testing on metal lap-shear coupons, most often aluminum. The standard test method is ASTM D1002, Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Tension Loading (Metal-to-Metal) Alumi-... 

A hypothetical adhesion bond is shown in Figure 1.3. Assume that the bond is tested in the tensile mode in which the two adherends are pulled apart in a direction perpendicular to the bond. There are different possibilities for the occurrence of failure. The surfaces involved in bond failure are called the locus of failure. 

The thickness, density, and residual stress in sintered films can be determined by the methods described above. The X-ray diHfaction method of determining stress is generally more suitable for sintered films since it does not require the removal of the film, as do the substrate curvature methods. The surface roughness can be measured with a profilometer, whereas the adhesion of the film to the substrate can be determined by a pull test, in which a wire is bonded to the film and then pulled with the force needed to remove the film from the substrate. The amount of camber or warpage can also be determined with a profilometer. Grain and pore sizes can also be determined by the same techniques used for bulk ceramics. 

Saret 633 was evaluated in a T-pull adhesion test using the EPDM formulation described in the materials section (see Section 8.3.1.1). The T-pull test measures the adhesion between rubber and a fibre. The fibre is placed in a mould and rubber is then added and cured. The fibre is then pulled in a perpendicular direction from the rubber and the force to break the adhesive bond is measured. The T-pull test is accomplished by using a special mould with a grid of trenches into which can he laid ruhher and perpendicular to the rubber a filament. By filling the trench half way with the ruhher the filament is embedded. After curing, the filament and rubber resemble a cross. The tensile tester is used to strip the rubber from the filament. 

As described in Section 6.4.1.2, it is also possible to use shear testing to determine the adhesive strength of the metallization on MID [175]. An alternative to shear testing is to use a hooked chisel for pull-testing the legs of components and wire bonds. This can often be accomplished using the same system technology. 

In the push out test [93], the fiber is pushed into the matrix rather than being pulled out. The test allows the measurement of two quantities, Fdcb (the force at which debonding occurs) and F/., (the force needed to push the fiber through the matrix sample if it is thin enough). The bond shear strength Tdeb is calculated using the shear lag theory ... 

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