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A bond tester is a scientific instrument used to measure the mechanical strength of bonds, evaluate bond strength distributions or determine compliance with specified bond strength requirements of the applicable acquisition document. [1]
Electrical and thermal bonds are such an integral part of electronic and semiconductor construction that they may often be taken for granted. Modern electronic assembly methods employ a myriad of bonding processes, each one a vital step in the manufacture of the final product. A typical consumer product such as a laptop computer may contain hundreds of thousands of bonds yet if one fails it will probably result in a system breakdown.[ citation needed ]
There are at least three means of bond testing: [2]
Typically a load is applied to a bond by a hook or shear tool, whereafter a force measurement is taken and the failure mode of the tested sample is recorded. More often than not bond tests are destructive and samples are scrapped after testing. In aerospace and medical applications, non destructive testing is common, whereby the bond is loaded up to a point to reveal nonacceptable bonds while avoiding damage to acceptable bonds.[ citation needed ]
For an automatic test PC controlled moving table allows any number of bonds to be tested automatically from a stored program. Results can be analysed and output immediately or exported in a number of data base formats for subsequent analysis as desired. Powerful extended capabilities enable measurements such as force/time or force/distance curves to be made and deliver more data about the quality of the bond tested.[ citation needed ]
The most common test types performed on a bond tester are the wire pull test, which generally puts an upward force on a gold/aluminum/silver/copper wire, and the die shear test, which generally comprises loading a die from the side. When equipped with tweezers, bond testers may also perform cold bump pull tests. During such a test, a solder ball down to 50 μm in diameter is reform it to the shape something like a mushroom and then pulled off the surface. Modern bond testers can perform a wide variety of tests with high precision, because automation eliminates human influence on the measurement.[ citation needed ]
Two industry leaders are DAGE (acquired by Nordson in 2006) [3] and xyztec. [4]
MIL-STD-883, JEDEC and other standards are commonly followed in the industry.[ citation needed ]
Wire bonding is a method of making interconnections between an integrated circuit (IC) or other semiconductor device and its packaging during semiconductor device fabrication. Wire bonding can also be used to connect an IC to other electronics or to connect from one printed circuit board (PCB) to another, although these are less common. Wire bonding is generally considered the most cost-effective and flexible interconnect technology and is used to assemble the vast majority of semiconductor packages. Wire bonding can be used at frequencies above 100 GHz.
The Rockwell scale is a hardness scale based on indentation hardness of a material. The Rockwell test measures the depth of penetration of an indenter under a large load compared to the penetration made by a preload. There are different scales, denoted by a single letter, that use different loads or indenters. The result is a dimensionless number noted as HRA, HRB, HRC, etc., where the last letter is the respective Rockwell scale. Larger numbers correspond to harder materials.
Timken OK Load is a standardized measurement that indicates the possible performance of extreme pressure (EP) additives in a lubricating grease or oil. The units of measurement are pounds-force or kilograms-force. This measurement is performed using a special test machine and standard block and ring test specimens.
Electric resistance welding (ERW) is a welding process in which metal parts in contact are permanently joined by heating them with an electric current, melting the metal at the joint. Electric resistance welding is widely used, for example, in manufacture of steel pipe and in assembly of bodies for automobiles. The electric current can be supplied to electrodes that also apply clamping pressure, or may be induced by an external magnetic field. The electric resistance welding process can be further classified by the geometry of the weld and the method of applying pressure to the joint: spot welding, seam welding, flash welding, projection welding, for example. Some factors influencing heat or welding temperatures are the proportions of the workpieces, the metal coating or the lack of coating, the electrode materials, electrode geometry, electrode pressing force, electric current and length of welding time. Small pools of molten metal are formed at the point of most electrical resistance as an electric current is passed through the metal. In general, resistance welding methods are efficient and cause little pollution, but their applications are limited to relatively thin materials.
Indentation hardness tests are used in mechanical engineering to determine the hardness of a material to deformation. Several such tests exist, wherein the examined material is indented until an impression is formed; these tests can be performed on a macroscopic or microscopic scale.
A heat sealer is a machine used to seal products, packaging, and other thermoplastic materials using heat. This can be with uniform thermoplastic monolayers or with materials having several layers, at least one being thermoplastic. Heat sealing can join two similar materials together or can join dissimilar materials, one of which has a thermoplastic layer.
In materials science and solid mechanics, residual stresses are stresses that remain in a solid material after the original cause of the stresses has been removed. Residual stress may be desirable or undesirable. For example, laser peening imparts deep beneficial compressive residual stresses into metal components such as turbine engine fan blades, and it is used in toughened glass to allow for large, thin, crack- and scratch-resistant glass displays on smartphones. However, unintended residual stress in a designed structure may cause it to fail prematurely.
Delamination is a mode of failure where a material fractures into layers. A variety of materials, including laminate composites and concrete, can fail by delamination. Processing can create layers in materials, such as steel formed by rolling and plastics and metals from 3D printing which can fail from layer separation. Also, surface coatings, such as paints and films, can delaminate from the coated substrate.
Ultrasonic testing (UT) is a family of non-destructive testing techniques based on the propagation of ultrasonic waves in the object or material tested. In most common UT applications, very short ultrasonic pulse waves with centre frequencies ranging from 0.1-15 MHz and occasionally up to 50 MHz, are transmitted into materials to detect internal flaws or to characterize materials. A common example is ultrasonic thickness measurement, which tests the thickness of the test object, for example, to monitor pipework corrosion and erosion. Ultrasonic testing is extensively used to detect flaws in welds.
In materials science, hardness is a measure of the resistance to localized plastic deformation, such as an indentation or a scratch (linear), induced mechanically either by pressing or abrasion. In general, different materials differ in their hardness; for example hard metals such as titanium and beryllium are harder than soft metals such as sodium and metallic tin, or wood and common plastics. Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, hardness can be measured in different ways, such as scratch hardness, indentation hardness, and rebound hardness. Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity. Common examples of hard matter are ceramics, concrete, certain metals, and superhard materials, which can be contrasted with soft matter.
A direct shear test is a laboratory or field test used by geotechnical engineers to measure the shear strength properties of soil or rock material, or of discontinuities in soil or rock masses.
A universal testing machine (UTM), also known as a universal tester, universal tensile machine, materials testing machine, materials test frame, is used to test the tensile strength (pulling) and compressive strength (pushing), flexural strength, bending, shear, hardness, and torsion testing, providing valuable data for designing and ensuring the quality of materials. An earlier name for a tensile testing machine is a tensometer. The "universal" part of the name reflects that it can perform many standard tests application on materials, components, and structures.
A triaxial shear test is a common method to measure the mechanical properties of many deformable solids, especially soil and rock, and other granular materials or powders. There are several variations on the test.
Weld quality assurance is the use of technological methods and actions to test or assure the quality of welds, and secondarily to confirm the presence, location and coverage of welds. In manufacturing, welds are used to join two or more metal surfaces. Because these connections may encounter loads and fatigue during product lifetime, there is a chance they may fail if not created to proper specification.
The MIL-STD-883 standard establishes uniform methods, controls, and procedures for testing microelectronic devices suitable for use within military and aerospace electronic systems including basic environmental tests to determine resistance to deleterious effects of natural elements and conditions surrounding military and space operations; mechanical and electrical tests; workmanship and training procedures; and such other controls and constraints as have been deemed necessary to ensure a uniform level of quality and reliability suitable to the intended applications of those devices. For this standard, the term "devices" includes monolithic, multichip, film and hybrid microcircuits, microcircuit arrays, and the elements from which the circuits and arrays are formed. This standard is intended to apply only to microelectronic devices.
Reliability of a semiconductor device is the ability of the device to perform its intended function during the life of the device in the field.
In the field of industrial ultrasonic testing, ultrasonic thickness measurement (UTM) is a method of performing non-destructive measurement (gauging) of the local thickness of a solid element based on the time taken by the ultrasound wave to return to the surface. This type of measurement is typically performed with an ultrasonic thickness gauge.
A pull-off test, also called stud pull test, is a type of test in which an adhesive connection is made between a stud and a carrier by using a glue, possibly an epoxy or polyester resin, that is stronger than the bond that needs to be tested. The force required to pull the stud from the surface, together with the carrier, is measured. Simple mechanical hand-operated loading equipment has been developed for this purpose. When higher accuracy is required, tests can be performed with more advanced equipment called a bond tester. A bond tester provides more control and possibly automation. Applying the glue automatically and curing with UV light is the next step in automation. This methodology can also be used to measure direct tensile strength or/and the bond strength between two different layers.
The wafer bond characterization is based on different methods and tests. Considered a high importance of the wafer are the successful bonded wafers without flaws. Those flaws can be caused by void formation in the interface due to unevenness or impurities. The bond connection is characterized for wafer bond development or quality assessment of fabricated wafers and sensors.
Welding of advanced thermoplastic composites is a beneficial method of joining these materials compared to mechanical fastening and adhesive bonding. Mechanical fastening requires intense labor, and creates stress concentrations, while adhesive bonding requires extensive surface preparation, and long curing cycles. Welding these materials is a cost-effective method of joining concerning preparation and execution, and these materials retain their properties upon cooling, so no post processing is necessary. These materials are widely used in the aerospace industry to reduce weight of a part while keeping strength.
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