Infineon Technologies Ag

Infineon Technologies North America Corp.

Syed Shoaib Hasan Zaidi

Alois Gutmann

Gangadhara Swami Mathad

Gary Williams

The properties of features formed in a substrate are measured. Lenslet array illumination is used to illuminate regions of a substrate so that the features of interest occupy a greater proportion of the illuminated area. The signal-to-noise ratio of the measurement signal is therefore increased, and the sensitivity of the measurement is thus improved.

Optical measurement of device features using lenslet array illumination

A method and mask to improve measurement of alignment marks is disclosed. An exemplary embodiment of the invention includes a resist mask with a patterned alignment mark comprising an assemblage of features whose spacing is smaller than the wavelength of light used to measure the alignment. In a preferred embodiment, an alignment mark patterning process alters the appearance of the alignment mark and renders an enhanced contrast with the substrate background.

Mask and method for using the mask in lithographic processing

There is provided a method for measuring planarized features on a wafer of a semiconductor device. The planarized features on the wafer are illuminated. A reflected light beam with respect to the planarized features is detected. Optical characteristics of the reflected light beam are analyzed to determine information corresponding to the planarized features. Preferably, the analyzing step maximizes an analysis of the optical characteristics based upon a simplified geometry of the planarized features with respect to a geometry of similar, un-planarized features. Moreover, preferably, the analyzing step maximizes an analysis of the optical characteristics based upon a reduction in complexity of the planarized features due to a similarity in refractive indexes corresponding to a bulk silicon substrate and a poly silicon fill of the semiconductor device.

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Poughkeepsie, NY, United States of America

Syed Shoaib Hasan Zaidi