晶圓厚度及翹曲檢測技術發展

Development of Wafer Thickness and Warpage Measurement Techniques

王浩偉 ； 張奕威 ； Abraham Mario Tapilouw ； 張樂融

《機械工業雜誌》 483期 (2023/06) Pp. 57-64

摘要

隨著半導體尺寸微縮趨勢，晶圓厚度越來越薄，對表面的要求也越來越高。晶圓翹曲或厚度變化過大，將導致晶圓破裂和後續製程的偏差，非接觸精確量測和反饋總厚度變異thickness（TTV, Total Thickness Variation）、翹曲（Warp）、彎曲（Bow） 資料，對製程良率至關重要。但不同的晶圓厚度範圍、晶圓表面粗度、線上檢測等要求，將對量測方法有所限制，本文將比較各量測方法的適用性，並就共焦方法的量測原理、架構、量測比對，及未來需求發展作進一步介紹。

關鍵字

晶圓厚度 ； 晶圓厚度變異 ； 晶圓翹曲 ； 彩色共焦

並列摘要

Along with the trend of in semiconductor fabrication to achieve smaller pattern dimension, wafer thickness is getting thinner while the requirements for wafer surface quality is stricter. The key factors are wafer warpage and thickness variation, the larger wafer warpage and thickness variation the lower quality of the end products and even could leads causes wafer to break. Thus, there is a demand for an accurate non-contact measurement system to measure wafer thickness variation (TTV) and wafer warpage to enable stricter monitoring of the quality of produced wafers. However, every measurement technique also has physical limitation and parameters that can be measured, e.g. thickness, surface roughness, measurement time, etc. This article briefly discusses different measurement techniques and their suitable application areas, and also introduces principles of developed chromatic confocal sensor-based wafer measurement system, calibration procedure, measurement data reconciliation, and also other challenges to be tackled for future developments.

並列關鍵字

Wafer Thickness ； TTV ； Wafer Warp ； Chromatic Confocal

參考文獻

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