Wenhe Yang, Nan Lin, Xin Wei, Yunyi Chen, Sikun Li, Yuxin Leng, J. Shao
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引用次数: 0
Abstract
Overlay (OVL) for patterns placed at two different layers during microchip production is a key parameter that controls the manufacturing process. The tolerance of OVL metrology for the latest microchip needs to be at nanometer scale. This paper discusses the influence on the accuracy and sensitivity of diffraction-based overlay (DBO) after developing inspection and after etching inspection by the asymmetrical deformation of the OVL mark induced by chemical mechanical polishing or etching. We show that the accuracy and sensitivity of DBO metrology can be significantly improved by matching the measuring light wavelength to the thickness between layers and by collecting high-order diffraction signals, promising a solution for future OVL metrology equipment.
期刊介绍:
Chinese Optics Letters (COL) is an international journal aimed at the rapid dissemination of latest, important discoveries and inventions in all branches of optical science and technology. It is considered to be one of the most important journals in optics in China. It is collected by The Optical Society (OSA) Publishing Digital Library and also indexed by Science Citation Index (SCI), Engineering Index (EI), etc.
COL is distinguished by its short review period (~30 days) and publication period (~100 days).
With its debut in January 2003, COL is published monthly by Chinese Laser Press, and distributed by OSA outside of Chinese Mainland.