Fuminori Hayano

Method for wafer edge profile extraction using optical images obtained in edge defect inspection process

It is becoming increasingly important to monitor wafer edge profiles in the immersion lithography era. A Nikon edge defect inspection tool acquires the circumferential optical images of the wafer edge during its inspection process. Nikons unique illumination system and optics make it possible to then convert the brightness data of the captured images to quantifiable edge profile information. During this process the wafers outer shape is also calculated. Test results show that even newly shipped bare wafers may not have a constant shape over 360 degree. In some cases repeated deformations with 90 degree pitch are observed.

New Measurement Technology for CD and Pattern Profile Variation using Optical Fourier Space

As well as measuring CD, monitoring pattern profile is becoming important for semiconductor metrology. Illuminating the wafer and detecting the reflective light, reflective light intensity in the Fourier space includes the information of CD and pattern profile variation by form birefringence effect. CD change and profile variation could be detected separately for the actual wafer. Mathematical simulation is presented the background of our unique approach. The detail results of CD and pattern profile monitor is shown in this paper.

New Inspection Technology for Hole Pattern by Fourier Space on hp 4x-nm Generation

We tried to detect the CD variation of the 4x generation hole pattern using the diffraction light on Fourier space with the polarized light and the modified illumination. The new technology named DD (Dual Diffraction) method has been developed based on the optical simulation and the experimental approaches. We introduce the case of detection for the diameter variation on a multi-layered hole pattern with new method.