Abstract:
A method and system are presented for use in model-based optical measurements in patterned structures. The method comprises: selecting an optimal optical model for interpretation of optical measured data indicative of optical response of the structure under measurements. The selection of the optimal optical model comprises: creating a complete optical model with floating parameters defining multiple configurations of said complete model including one or more model configurations describing an optical response of the structure under measurements, utilizing the complete model for predicting a reference optical response from the structure and generating corresponding virtual reference data, and using the virtual reference data for selecting the optimal optical model for interpretation of the optical measured data.
Abstract:
A method for use in planning metrology measurements, the method comprising: providing inverse total measurement uncertainty (TMU) analysis equations for upper and lower confidence limits TMU UL and TMU LL of the TMU being independent on prior knowledge of measurements by a tool under test (TuT) and a reference measurement system (RMS), thereby enabling estimation of input parameters for said equations prior to conducting an experiment of the TMU analysis; and determining at least one of a total number N of samples to be measured in the TMU analysis and an average number n s of measurements per sample by the RMS.
Abstract:
A sample comprising an overlay target is presented. The overlay target comprises at least one pair of patterned structures, the patterned structures of the pair being accommodated in respectively bottom and top layers of the sample with a certain vertical distance h between them, wherein a pattern in at least one of the patterned structures has at least one pattern parameter optimized for a predetermined optical overlay measurement scheme with a predetermined wavelength range.
Abstract:
An optical method and system are presented for use in measurement of isolated features of a structure. According to this technique, Back Focal Plane Microscopy (BFM) measurements are applied to a structure and measured data indicative thereof is obtained, wherein the BFM measurements utilize dark-field detection mode while applying pinhole masking to incident light propagating through an illumination channel towards the structure, the measured data being thereby indicative of a scattering matrix characterizing scattering properties of the structure, enabling identification of one or more isolated features of the structure.
Abstract:
An optical system is presented for use in measuring in patterned structures having vias. The optical system comprises an illumination channel for propagating illuminated light onto the structure being measured; a detection channel for collecting light returned from the illuminated structure to a detection unit; and an attenuation assembly accommodated in the illumination and detection channels and being configured and operable for selectively attenuating light propagating along the detection channel, the attenuation creating a predetermined condition for the selectively attenuated light, said predetermined condition being defined by a predetermined ratio between a first light portion corresponding to a dark field condition and a second light portion corresponding to a bright field condition in said selectively attenuated light, detected selectively attenuated light being therefore indicative of at least one parameter of the via being illuminated.
Abstract:
A method of controlling a manufacturing process, the method including the steps of a) providing a testing area with a periodic structure, where the periodic structure includes a series of sets of patterned features, b) illuminating the periodic structure with a light, thereby producing a non-zero order diffraction signal, c) collecting the diffraction signal to produce a test signature, d) matching the test signature with a reference signature, where the reference signature was previously produced by performing steps a), b), and c) with respect to a reference structure that is at least similar to the periodic structure, and e) controlling a manufacturing process using a control setting set associated with the matching reference signature.
Abstract:
A method and system are presented for use in measuring in complex patterned structures. A full model and at least one approximate model are provided for the same measurement site in a structure, said at least one approximate model satisfying a condition that a relation between the full model and the approximate model is defined by a predetermined function. A library is created for simulated data calculated by the approximate model for the entire parametric space of the approximate model. Also provided is data corresponding to simulated data calculated by the full model in selected points of said parametric space. The library for the approximate model data and said data of the full model are utilized for creating a library of values of a correction term for said parametric space, the correction term being determined as said predetermined function of the relation between the full model and the approximate model. This enable to process measured data by fitting said measured data to the simulated data calculated by the approximate model corrected by a corresponding value of the correction term.
Abstract:
A system and method are presented for use in inspection of patterned structures. The system comprises: data input utility for receiving first type of data indicative of image data on at least a part of the patterned structure, and data processing and analyzing utility configured and operable for analyzing the image data, and determining a geometrical model for at least one feature of a pattern in said structure, and using said geometrical model for determining an optical model for second type of data indicative of optical measurements on a patterned structure.
Abstract:
A method and a system for optical measuring in a structure having a pattern in the form of spaced-apart parallel elongated regions of optical properties different from that of spaces between said regions. The system comprises a broadband illuminator (8) for generating incident radiation, a spectrophotometer arrangement (30) for detecting a spectral response of the structure to the incident radiation, and an optical arrangement (2) for directing the incident light to the structure and collecting the response of the structure, said optical arrangement (2) comprising a numerical aperture (32) selectively limiting the range of at least one of light incidence or collecting angles in direction substantially perpendicular to longitudinal axes of said elongated regions of the pattern.
Abstract:
A method and system are presented for measuring in a patterned structure to thereby enabling to control a process. An image of at least a region of patterned structure formed by light returned from the illuminated region is acquired and analysed to determine sites of the structure to which electrical measurements are to be applied. Electrical measurements to the predetermined sites of the structure are applied and measured data indicative of at least one parameter of the structure is generated for adjusting operating conditions of the process.