Our patent US9933372B2, granted on April 3, 2018, focuses on a breakthrough in lighting dome technology, particularly for inspecting semiconductor wafers. As a holder of this patent, we have innovated a system that addresses the critical challenges faced during wafer inspection, such as uneven lighting and unwanted reflections.
Our invention includes a reflective dome with a gradient surface that enhances the evenness of light distribution. This allows for homogenous illumination of highly reflective surfaces like wafers, which has historically been difficult with conventional domes. The reflectance gradient ensures that light is diffused effectively, reducing glare and reflection that could otherwise interfere with visual or automated inspections.
We have also incorporated a small aperture in the dome for image sensing. By reducing the aperture size, we maximize the reflective surface area, thereby improving lighting conditions while maintaining the quality of the captured images. This design effectively eliminates the problem of lens reflection contaminating the inspection images.
Another highlight of this patent is the use of broad-spectrum light sources, such as white light, which enhances the clarity of the images, making defect detection more reliable. This is a significant improvement over narrow-spectrum light sources, which can sometimes cause false positives or miss important details.
Additionally, this patent covers backlighting techniques, where the light source is placed behind the wafer, further optimizing the inspection process by eliminating shadow effects and allowing for a clearer view of the wafer’s surface. This design is highly effective in detecting residues and defects on wafers, especially during the manufacturing process.
In essence, our patent revolutionizes wafer inspection technology by delivering a cost-effective, efficient, and reliable solution, one that significantly improves upon prior art in terms of both design and functionality. Our solution makes it easier for the semiconductor industry to ensure the quality and consistency of wafers throughout production.