Wire bonding is a key process in semiconductor production. Extremely fine wires with diametres of 15 to 75 micrometres create tiny electrical connections between a semiconductor chip and other components. The distances between the bond wires are often less than 100 micrometres.
Wire bonding
Any deviation, however small, can lead to connection errors. Wire bonding therefore requires the highest precision and forms the basis for producing high-performance electronics, which are used in many different applications.
F&S BONDTEC Semiconductor GmbH from Braunau, Austria, relies on image processing technology with industrial cameras from IDS Imaging Development Systems GmbH to precisely determine wire positions and for quality assurance.
Application
The operator only has to change the wire or tool on the bonder occasionally and take care of loading and unloading
Wire bonders are available with various degrees of automation. With manual devices, each bond position must be approached manually before the corresponding connections can be made. Semi-automatic machines automatically position the wire after the first bond to create a wire bridge.
Fully automatic machines use a structure recognition system to determine the position of the chips. Here, the production of all wire bridges is completely automatic. The operator only has to change the wire or tool on the bonder occasionally and take care of loading and unloading.
Image processing
F&S Bondtec uses image processing with IDS industrial cameras for various tasks in the production process, especially in the semi-automatic machines of the 56i series and the automatic wire bonders of the 86 series.
"Our wire bonds connect previously placed microchips or other components with different contact points on printed circuit boards and breathe life into the chips," explains Johann Enthammer, Managing Director and CTO at F&S Bondtec.
Bonding parametres
Ultrasonic amplitude, force, time, or the movement sequence for setting up the bonding bridges must be programmed
"However, positional inaccuracies of the components can occur during the upstream processes. Our machines have to determine these positional inaccuracies using the IDS camera image and our image recognition software and update the wire bond positions accordingly."
For each bonding process, parametres such as ultrasonic amplitude, force, time, or the movement sequence for setting up the bonding bridges must also be programmed in advance. The camera's image feed is also used when creating these programmes.
Image recognition library
For example, you can drag a wire in the live image and change its position. The axes can also be adjusted by clicking on the image.
On the software side, the Austrian company relies on a specially developed image recognition library that works with position/pixel mapping, greyscale recognition, and edge detection, for example.
Visual assessments of bond connections
Once the bonding process is complete, the camera is used again, as Johann Enthammer explains, "After welding, the wire bonds are visually checked by the operator via the camera image."
"Among other things, the position and shape of the bond bridges are assessed. The camera image therefore has more than just one function during the bonding process."
uEye XCP models
At just 29 x 29 x 17 millimetres, they are the smallest housed IDS cameras with C-mount
Between one and seven industrial cameras are used per system. Depending on the type, these can be particularly compact and cost-effective uEye XCP models. At just 29 x 29 x 17 millimetres, they are the smallest housed IDS cameras with C-mount and have a completely enclosed die-cast zinc housing.
Their screw-type USB micro-B connection and compatibility with the Vision Standard (U3V / GenICam) simplify integration.
uEye CP cameras
F&S Bondtec also uses uEye CP cameras. These tiny powerhouses offer maximum functionality with extensive pixel pre-processing and are also perfect for multi-camera systems thanks to the internal 120 MB image memory for buffering image sequences.
Users can choose from a large number of modern CMOS sensors. They also score points with a compact housing measuring just 29 x 29 x 29 millimetres.
Camera selection
The small design of the models and the large number of different sensors were important criteria when selecting the camera, as was the low thermal expansion.
However, the free IDS peak software development kit with all the programming interfaces and software tools required for operating and programming the cameras was also crucial. Easy-to-understand convenience functions ensure an intuitive programming experience and quick and simple commissioning of the industrial cameras.
Plug-and-play functions
Johann Enthammer confirmed, "The driver shows very stable runtime behaviour. The easy-to-programme API and the plug-and-play functions with running software convinced us."
"This is because there are many different use cases for our systems that can be implemented with the API without any problems. Our machines can be equipped with up to seven different bond heads. A different IDS camera can be integrated into each one."
Outlook
In addition to standard products, the company develops special machines and customised software solutions
The wire bonders from F&S Bondtec ensure stable connections in semiconductor production. With the help of integrated image processing, the manufacturing quality and productivity of the systems can be further increased and rejects avoided.
At the same time, the cameras make work easier for the operators. In addition to standard products, the company develops special machines and customised software solutions that also use AI models.
Efficiency, precision, and quality
"We see a lot of potential for the use of artificial intelligence in our applications in the future," says Johann Enthammer.
Image processing opens up completely new potential, especially in conjunction with AI, particularly in terms of efficiency, precision, and quality. And thanks to IDS's broad portfolio, the right "eye" can be found for every application - for micrometre-precise results.
Camera
F&S Bondtec uses various uEye industrial cameras, for example:
uEye XCP - the industry's smallest housing camera with C-mount
- Model used: U3-3680XCP Rev.1.2
- Camera family: uEye XCP
uEye CP - incredibly fast, powerful, future-proof
- Modell used: U3-3040CP Rev.2.2
- Camera family: uEye CP
Customer
F&S Bondtec covers the desktop bonder and tester segment worldwide and offers a wide range of production and test equipment. It extends to the desktop micro-factory, which combines all wire bonding processes and all test methods in one machine base.
Since the company was founded in 1994, several thousand wire bonders and bond testers have left the factory and are in use in many laboratories, development departments, pilot production lines, and production facilities around the world.