Modern imaging technologies such as 3D imagers, CT scanners, digital x-ray devices, and endoscopes require specifically precise high-resolution medical imaging sensors and sensor arrays. Newly developed components such as advanced semiconductors and more powerful chips also demand for more sophisticated sensor packaging technologies. New material selections also help to ensure the long-term functional reliability of imaging devices and components.
In the near future, innovative technologies will further reduce the power consumption and heat generation of imaging sensors – at the highest quality and competitive costs.
Challenge 1: Placement accuracy
Maximum precision is essential in the placement of components such as prisms or apertures to the die surface. In endoscopes it might be necessary to attach the optics directly to the chip at pixel size accuracy.
Therefore, it is important to ensure that the supplier has the required expertise regarding materials and die-bonding quality and that the equipment is accurate enough to process the ultra-compact components.
Challenge 2: Flatness
Placement accuracy also includes aspects such as flatness and tilt in order to enable sharp imaging in the focal plane. The supplier must guarantee flatness over the device’s entire temperature range.
Challenge 3: Cleanliness
As dirt or dust can cause critical quality issues in the production of high-precision medical imaging sensors and arrays, the entire construction process has to take place in an ultra-clean environment. Handling and packaging processes in this sector typically require class 100 clean room facilities in order to avoid rejects.
Challenge 4: Product and material handling
The contamination of imager packaging can be best avoided if all handling steps from the dicing of substrates and semiconductor wafers to the assembly and testing are performed in one clean room – without the risk of damages during transportation.
Challenge 5: Material interconnection
In assembled arrays, the wire bonds must work reliably to ensure the perfect functionality of all connections. If one connection does not work, the entire module has to be discarded. Sound material interconnection is essential for high-quality, cost-effective sensor solutions.
Choosing the right packaging partner
Packaging suppliers must be evaluated considering the following aspects:
- Scalability in product volume and size
- Knowledge and expertise enabling the joint development of custom-tailored imager designs and packaging technologies
- Technology transfer and close collaboration between the packaging partner and the OEM to deliver solutions that perfectly meet the OEM’s requirements.
- Quality systems: Quality certifications and external audits ensure that the supplier’s processes are aligned to common quality standards.
Image sensor and packaging technologies are in a phase of transition: Highly efficient CCD and CMOS structures will further reduce power consumption and not even require active cooling. New packaging technologies will take advantage of organic substrate materials. Chip on board (COB) concepts will allow for increasingly compact designs and help to further reduce costs.
Would you like to learn more on the latest developments in medical image sensor design? Our white paper reveals the 5 challenges in the manufacturing of high-end imaging sensor solutions.