Wire Bonding insights at your fingertips
Here we regularly present news related to wire bonding. These may be our own activities, brief food for thought or summaries of interesting publications. So it's worth spending a little more time here.
Thermosonic Bonding: Analyzing the Effects of Ultrasound, Heat, and Metallurgical Processes on Gold and Copper Wire Bonds
In the field of microelectronics, wire bonding represents a pivotal process, utilized for the interconnection of minute wires between a chip and a substrate. The research project is concerned with the comprehension and enhancement of the ball bonding process, which entails the utilization of gold or copper wires.
Evolution of Semiconductor Bonding Wires: From Gold to Copper and Silver Over 25 Years
This study examines the evolution of bonding wires utilized in semiconductor electronics over the past 25 years, with a particular emphasis on gold (Au), copper (Cu), and the emerging utilization of silver (Ag) wires. Bonding wires are of paramount importance for the interconnection of semiconductor chips with other components in electronic devices, such as mobile phones and computers.
How Ultrasonic Power and Intermetallic Formation Work in Thermosonic Ball Bonding
This research project is concerned with the subject of thermosonic ball bonding, a process which is employed in the field of microelectronics for the purpose of connecting components of a relatively small scale. The objective of the study is to enhance comprehension of the manner in which materials behave during this process. Thermosonic bonding is a process that employs the combination of heat, ultrasonic vibrations, and pressure to create connections between a wire, typically gold or copper, and a substrate, such as aluminum.
The study examines the formation of bonds and the microscopic alterations in the materials utilized.
Can Copper Clips Solve the Reliability Problem in Power Electronics? A Look into Metallization Failures and Degradation
The publication's primary focus is on the reliability and failure mechanisms of the aluminum metallization layer utilized in power electronics. Power electronics, including the MOSFET (a type of transistor), are integral components in a multitude of devices, such as automobiles. Power cycling tests are typically conducted to observe the behavior of materials under conditions of elevated temperature and mechanical stress. Over time, these tests simulate the effects of real-world conditions on the chip, including temperature changes, which can cause wear and tear on the aluminum layer. This study examines the impact of switching from traditional aluminum wire bonds to copper clips on the performance and reliability of the module.
Bonding battery cells in the FASTTUBE TEAM racing car 2022
Since 2005, around 80 students from the FaSTTUBe team at the TU Berlin have been building a new racing car every year to take part in international and European Formula Student design and racing competitions. Since 2018 with an electric car and since 2020 driverless. Bond-IQ joined as a platinum sponsor in 2022, using thick wire bonding to wire the battery modules (including the driver architecture), which the development team converted from bags to 18650 cells in an impressive 3 months. As this technology is new territory for the FaSTTUBe team, we are always on hand to provide support. Whether it's a quick visit to check on a detail or a lightning-fast turnaround for a prototype. The FaSTTUBE team is fighting all the uncertainties and delivery difficulties of 2022. We will always be close at hand and will support you with all our strength and resources.
Racing Update 2023 - we improve the battery for an even better racing car
Racing Update 2023 - we improve the battery for an even better racing carTogether with the new FaSTTUBe team we are working on fixing the last small bugs in the first battery from 2022. Max – one of the powertrain team leaders – has joined us for this purpose. Process optimization and design are now in his hands. With the nickel-plated busbars this time, the bonding process is much more stable than with the water-jet-cut, unplated copper. As a result, we were able to significantly reduce the failure rate and complete the assembly of all 9 battery packs in a third of the time.
A New Approach to Wire Bond Testing Could Improve High-Power Electronics Reliability
The objective of this study is to enhance the reliability assessment of wire bonds in power electronics, with a particular emphasis on the Highly Accelerated Lifetime Testing (HALT) methodology. In the context of electronic devices, wire bonding refers to a technique whereby thin wires are used to connect semiconductor components. With the passage of time, these bonds may succumb to failure as a consequence of wear and tear, particularly in the context of extreme temperature fluctuations. The researchers developed a mechanical testing method to simulate the failure that would naturally occur in wire bonds over time, thereby enabling them to predict the longevity of the bonds in real-world conditions.
New Standards in Wire Bonding: A Detailed Analysis of DVS-2811 for Automotive and Power Electronics
The authors examine the advancements in wire bonding standards for the European automotive and power electronics industries. Wire bonding is a method of creating electrical connections between semiconductor devices and their packaging using thin wires, which are of critical importance for the production of microelectronics, such as batteries. The study concentrates on the DVS-2811 standard, which provides guidance on the testing and inspection of wire bonds.
1st EBL Young Researcher Award at the EBL 2018
Felix Fischer (Microsystems Engineering student at HTW Berlin) successfully presented his master's thesis in a paper and a presentation at the EBL Conference 2018, winning the prize for the best presentation. The thesis was carried out at Fraunhofer IZM Berlin and supported by Bond-IQ with extensive experiments and know-how, with the aim of investigating the semi-autocatalytic Au plating system on electrolessly deposited NiP for wire bonding applications with AlSi1 wire, e.g. for chip-on-board (COB) technology. The ability of the plating system to significantly reduce nickel corrosion during the deposition process and thus counteract coating adhesion problems during bonding is of great interest to users requiring stable bonding processes. The work has shown, in some cases with complex analysis, that there are still pitfalls in the technology and that further development is needed to solve the problem. Felix Fischer is continuing his research on this topic at Fraunhofer IZM and Bond-IQ will support his work.
Racing Update 2024 - we are ready for the next step
We have designed the battery packs completely without bus bars. Direct connection of the battery cells, cooling through the back of the cells – i.e. wire bonding on the cathode and anode on one side of the battery cell – and 3 wires with a diameter of 500 µm per battery shoulder for maximum performance. Wire lengths of up to 20 mm that will not sag and cause short circuits despite the vibrations of driving. This allows us to achieve the highest possible level of miniaturization for this type of cell and significantly reduce weight for an even faster racing car.
Advanced bonding interface inspection technique for process optimization in heavy wire bonding
Presented at the IMAPS conference in October 2021, this paper presents a novel methodology for analyzing the interface formation of heavy wire-bonded contacts. By combining the BAMFIT (Bondtec Accelerated Mechanical Fatigue Interface Testing) method, 3D fracture pattern measurements, and customized evaluation algorithms, this approach provides accurate data on the bonded interface area. Unlike traditional shear testing, this method directly measures the bonded area, allowing for improved parameter tuning for different material systems. The study examined four wire types with similar mechanical properties, using design of experiment (DoE) techniques to identify process windows and material-specific insights. The results highlight the benefits of accurately measuring the bonded area and illustrate where conventional shear testing has limitations in detailed analysis. This work provides valuable guidance for optimizing bonding processes and material selection.
Revision of the wire bonding test standard DVS-2811
In February 2017, after more than 20 years, a revised version of the DVS-2811 test standard for wire bonding was published. From its start in September 2014 to its completion in December 2015, Bond-IQ worked intensively on the revision in a multi-client project, structuring and conducting the necessary experiments and coordinating the project. This work was done in close cooperation with Fraunhofer IZM Berlin. 25 project partners were involved and were fully convinced of the necessity and success of the project to revise the existing test standard. Just one year later, this was published as an official bulletin of the DVS Association under the previous number DVS-2811 with the addition of the version 02/2017. Since then, a comprehensive document for the testing of thin-wire and (still internationally unique) thick-wire bonded joints has been available. DVS Technical Bulletin 2811 is officially available from Beuth-Verlag in German and English.
Power Cycling and Wire Bond Reliability: The Critical Role of Wire Material and Diameter in Extending Lifetime
This research project examines the reliability of various types of aluminum heavy wire bonds utilized in power electronics, with a particular focus on their performance in MOSFET modules. Wire bonding is a common method used to connect electronic components, but the reliability of these bonds is of critical importance for long-term performance. The study examines the impact of varying aluminum wire materials and diameters on the durability of these wire bonds during power cycling, a process whereby the system is repeatedly turned on and off, resulting in temperature fluctuations.
Sintering and Copper Wire Bonding: Reducing Failure Rates in High-Thermal Power Modules
This paper presents a summary of the advancements in power electronic packaging, with a particular emphasis on the enhancement of reliability and performance under high temperatures. Power electronics are utilized in a multitude of devices to regulate electrical energy, and these systems encounter challenges due to the thermal stresses that are generated during operation. One area of focus is wire bonding, which involves the use of a metal wire to establish a connection between a semiconductor chip and other components.
✅ Here the case is clear 🧐🕵️✅
It is simply not possible to achieve a stable wire bonding process if the surface quality is constantly changing. It is the supplier's task to ensure a homogeneous and good quality. And it is up to the customer who wire bonds to specify this quality. The supplier has to know which characteristics are important and how they have to be inspected. A visual inspection is the minimum here and should at least check the following details:
• Local discolorations and stains
• Drying stains
• Flux residues
• Solder spots#
• Filmic contaminations, e.g. oils, fats, fingerprints
• Local holes, scratches, scores
• Scoring marks resulting from mechanical processing, e.g. brushing, polishing, grinding
• Test needle imprints
• Exposed copper or nickel
There are always two sides to a coin 🥉. Those who do not care and specify well, but leave everything to their supplier, are part of the problem. So if you don't care, you then don't have to be surprised when things often go wrong. If it is as clear as in the picture of this post, the case is clear and the delivered lot goes back to the supplier - but that also costs resources and time, valuable time.
Reducing Wire Bond Failure: How Adjusting Bond Foot Angles Improves Power Module Reliability
The study focuses on wire bonding, a critical process for connecting electronic components within power modules. Wire bonding creates connections between a semiconductor chip and its supporting structure (substrate). In this research, scientists are examining how different angles at which the wire touches the chip, known as the bond foot angle, affect the longevity of these bonds. A larger bond foot angle tends to reduce the life of the wire bond because it introduces additional stress during operation. The team used both experiments and simulations to test the effects of varying bond foot angles on wire bond reliability.
Advancements in Copper Ball-Wedge Wire Bonding: A Cost-Effective Alternative to Gold in Semiconductor Manufacturing
The literature review examines advancements in copper (Cu) ball-wedge bonding, a technique utilized to establish connections between wires in electronic devices. Historically, gold (Au) was the material of choice due to its resistance to corrosion. However, the increasing costs associated with gold have prompted the exploration of alternative materials, such as copper. Copper offers superior electrical performance, but it also presents challenges such as oxidation (rusting) and increased hardness, which complicate the bonding process.
Investigating the Inaccuracies in Wire Bonding Pull Testing and Introducing a New Analytical Model for Improved Quality Control
This study examines the process of wire bonding pull testing, which represents a pivotal quality control step in microelectronics, particularly in fields such as automotive and sensor manufacturing. The process of wire bonding entails the formation of connections between small wires and electronic components. It is of paramount importance to ensure that these bonds are robust in order to guarantee the reliability of the final product.
