Waferkrümmungsmessung

Waferkrümmungsmessung, also known as wafer curvature measurement, is a critical process in semiconductor manufacturing used to quantify the deviation of a silicon wafer from a perfectly flat surface. This deviation, often referred to as wafer bow or warp, can significantly impact subsequent processing steps and the performance of integrated circuits. The measurement is typically performed using optical metrology techniques.

One common method involves projecting a structured light pattern onto the wafer surface and observing its deformation through a camera. By analyzing the distortion of the projected pattern, the three-dimensional profile of the wafer can be reconstructed, allowing for precise measurement of the curvature. Another approach utilizes interferometry, where light waves reflected from the wafer surface interfere with a reference beam. The resulting interference pattern provides highly sensitive information about the wafer's topography.

Wafer curvature can arise from various factors, including stress induced during epitaxial growth, deposition of thin films, or variations in wafer thickness. Monitoring wafer curvature throughout the manufacturing process helps identify potential issues early on. Excessive bow or warp can lead to problems with photolithography alignment, resulting in misaligned features. It can also affect the wafer handling systems, causing jams or damage. Therefore, waferkrümmungsmessung is an essential quality control step to ensure the production of reliable and high-performing semiconductor devices.