Tresky Automation takes a consistently digital approach to the visual alignment of high-precision DIE bonding processes. The Digital Beamsplitter eliminates the need for a traditional optical beamsplitter and uses software to combine the images from an up-looking and a down-looking camera. This eliminates additional optical and mechanical parameters in the beam path. The technology also enables alignment tasks where conventional optical systems inherently reach their limits.
In traditional beamsplitter systems, light from different perspectives is combined using a physical beamsplitter. The additional glass required for this is located directly in the optical path and can reduce light output as well as cause reflections, ghost images or focus shifts. In addition, the mechanical-optical assembly must be precisely aligned.
Tresky follows a different approach
“Why should we still be merging two camera images using an additional piece of glass when we can solve this task more precisely and with far greater flexibility using digital methods? With our Digital Beamsplitter, we’re systematically shifting image merging from the optics to the software.”
The up-looking camera captures the chip, while the down-looking camera captures the substrate or the target position. Both images are then digitally merged and displayed to the user as a single alignment image.
See and align chips and substrates directly
The user can immediately see the chip structure, the target structure and the existing misalignment in a single view. Alignment can be performed directly using X, Y and theta. This means the operator does not have to assess the position solely based on abstract coordinates or indirect image information. Instead, the operator receives direct visual feedback on how the chip and substrate are actually positioned in relation to each other.
“We want to provide users with maximum transparency, especially during development, prototyping and high-mix applications. They see the actual alignment situation and can react to it immediately. This gives the customer full control over the alignment process.”
No beamsplitting glass, no light splitting
Since the Digital Beamsplitter does not require physical light splitting, the light output available to each camera is not split by an additional beamsplitter. At the same time, the cameras’ full sensor resolution can be utilized. Optical effects caused by the additional beamsplitter glass, such as focus shifts, reflections or ghost images, are also avoided. Likewise, no delicate mechanical-optical adjustment of a beamsplitter prism is required. This allows Tresky to specifically reduce the number of optical and mechanical variables within the alignment system.
The digital image processing also offers significantly greater flexibility. Parameters such as transparency, scaling, zoom, contrast, brightness, rotation or additional overlays can be adjusted via software to suit the specific application. What is defined by the physical optics in a traditional beamsplitter can be flexibly controlled via software in the Digital Beamsplitter.
The key difference: Optics can only show what is visible
The technological difference becomes particularly evident in applications where relevant chip structures or alignment marks are obscured by the pickup tool after pickup. A conventional optical system reaches a fundamental limit here: What is no longer physically visible cannot be displayed optically either.
Tresky’s Digital Beamsplitter goes one step further. The system can capture an image of the relevant chip structure immediately before pickup and save it as a reference. After the chip is picked up, this image is superimposed on the current live image of the substrate. This ensures that a structure that is important for alignment remains usable, even though it is already obscured by the pickup tool on the actual component at that point in time.
“This is exactly where it becomes clear that our Digital Beamsplitter isn’t simply a digital copy of an optical beamsplitter. We can use information for alignment that is no longer physically visible at the actual moment of alignment.”
More than just a digital replacement for an optical component
For Tresky, it is therefore not simply a matter of digitally replicating a traditional beamsplitter. Rather, the elimination of the physical beamsplitter paves the way for additional functions and new alignment strategies. The key point is not simply to replace an optical component with software. Instead, the software-based solution enables functions that are not possible with a purely optical system.
This offers specific advantages for users:
- no physical light splitting by an additional beamsplitter
- use of the cameras’ full sensor resolution
- no ghost images or focus shifts caused by beamsplitter glass
- no adjustment effort for a mechanical-optical beamsplitter
- direct visual control of the chip and target structure
- flexible software-based image display
- use of previously captured chip structures even after they are physically obscured
The Digital Beamsplitter is therefore particularly well-suited for demanding DIE bonding processes in research and development, prototyping, high-mix/low-volume manufacturing, photonics, optoelectronics and advanced packaging.
Digital alignment instead of optical compromises
With the Digital Beamsplitter, Tresky consistently pursues its philosophy of combining mechanical precision with intelligent digital process support. In high-precision DIE bonding, just a few micrometers can make all the difference in the process. The aim is therefore to visualize the actual alignment situation as precisely as possible while eliminating unnecessary optical and mechanical variables. The Digital Beamsplitter provides the necessary capabilities to achieve this.
Tresky Digital Beamsplitter
See the target.
Align both.
Learn more about the Digital Beamsplitter and the possibilities it offers for your DIE bonding processes.