Improved preciseness in die-bonding

Producing more chips per wafer is a constant goal of the semiconductor industry which leads to lower manufacturing costs. However, the smaller the chips are, the more fragile they become and the more difficult they are to handle. It is mostly in the post processing applications like separation, mounting, contacting and encapsulation that die-bonding systems face the major challenges. The same is true for their optical components.

The Amadyne company, from Bühl in Germany, is a specialist for assembly and handling systems for components. The SAM42 family, for example, represents such a system, which handles all post-processing steps and therefore offers huge flexibility. However, it is not as simple as that. The contacting process, the so-called wire bonding, is particularly demanding. Mechanically sensitive components with edge lengths between 200 µm and 40 mm have to be placed with micrometer precision in housings or on boards using a vacuum hook.

With fab1 Amadyne decided to design a new bonding system using the experience of the SAM42 family as a base. However, all important subsystems were to be re-implemented using state-of-the-art technology. It was necessary to offer even better accuracy and five times higher output but at not more than double the price. Basic technical design changes were: switching from Windows to Linux with a current Kernel, up-to-date LabVIEW as the development system, linear servomotors, decentralized I/O hardware, 1-3x digital VGA as well as special development of the vision software. A cost-efficient, robust camera system with good Linux support and fast, digital bus system was required to deliver high quality images. Afterwards, these images must be easily processed with software.

Finally, after a detailed market analysis the decision was made to take the mvBlueFOX. The significant reasons for this decision were the compact and robust design, the availability of a well documented Linux framework in C/C++, the USB 2.0 interface, the availability of different sensors in the same model range as well as a favorable price-performance ratio. The use of USB as the bus system proved to be unproblematic. Although there are enormous cost benefits, there are no recognizable disadvantages. Due to the well-thought-out software, integration in this project was possible with minimum effort. The mvBlueFOX was equipped with a modified version of the existing optics from the analog camera. With these simple optics the results exceeded all expectations. Using the default values, no image noise is measurable; the images are rich in contrast and show no artifacts. In the course of the prototype stage, the electrical and mechanical robustness was tested. The camera endures substantial longitudinal and lateral accelerations without a problem and shows an extremely high electromagnetic resistance.