Abstract:
A method is presented for optical control of the quality of a process of chemical mechanical planarization (CMP) performed by a polishing tool applied to an article having a patterned area. The article contains a plurality of stacks each formed by a plurality of different layers, thereby defining a pattern in the form of spaced-apart metal regions. The method is capable of locating at least one of residues, erosion and dishing conditions on the article. At least one predetermined site on the article is selected for control. This at least one predetermined site is illuminated, and spectral characteristics of light components reflected from this location are detected. Data representative of the detected light components is analyzed for determining at least one parameter of the article within the at least one illuminated site.
Abstract:
A method for measuring at least one desired parameter of a patterned structure having a plurality of features defined by a certain process of its manufacturing. The structure represents a grid having at least one cycle formed of at least two locally adjacent elements having different optical properties in respect of an incident radiation. An optical model, based on at lease some of the features of the structure is provided. The model is capable of determining theoretical data representative of photometric intensities of light components of different wavelengths specularly reflected from the structure and of calculating said at least one desired parameter of the structure. A measurement area, which is substantially larger than a surface area of the structure defined by the grid cycle, is illuminated by an incident radiation of a preset substantially wide wavelength range. Light component substantially specularly reflected from the measurement area is detected and measured data representative of photometric intensities of each wavelength within the wavelength range is obtained. The measured and theoretical data satisfies a predetermined condition. Upon detecting that the predetermined condition is satisfied, said at least one parameter of the structure is calculated.