Nova Measuring Instruments Ltd.

David Scheiner

Moshe Finarov

Vladimir Machavariani

Avi Ravid

Boaz Brill

Michael Winik

Yakov Lyubchik

Amit Weingarten

Shahar Gov

Rahamin Guliamov

Yoav Many

Alignment of layers during manufacture of a multi-layer sample is controlled by applying optical measurements to a measurement site in the sample. The measurement site includes two diffractive structures located one above the other in two different layers, respectively. The optical measurements include at least two measurements with different polarization states of incident light, each measurement including illuminating the measurement site so as to illuminate one of the diffractive structures through the other. The diffraction properties of the measurement site are indicative of a lateral shift between the diffractive structures. The diffraction properties detected are analyzed for the different polarization states of the incident light to determine an existing lateral shift between the layers.

Lateral shift measurement using an optical technique

Obtaining at least one of a cross-section profile, depth, width, slope, undercut and other parameters of via-holes by a non-destructive technique using an optical system having an illumination system for producing at least one light beam and directing it on a sample in a region of the structure containing at least one via-hole, a detection system configured and operable to collect a pattern of light reflected from the illuminated region, the light pattern being indicative of one or more parameters of said via-hole, and, a control system connected to the detection system, the control system comprising a memory utility for storing a predetermined theoretical model comprising data representative of a set of parameters describing via-holes reflected pattern, and a data processing and analyzing utility configured and operable to receive and analyze image data indicative of the detected light pattern and determine one or more parameters of said via-hole.

Optical system and method for measurement of one or more parameters of via-holes

The present invention provides a novel system and method for obtaining at least one of a cross-section profile, depth, width, slope, undercut and other parameters of via-holes by non-destructive technique. The optical system comprises an illumination system for producing at least one light beam and directing it on a sample in a region of the structure containing at least one via-hole; a detection system configured and operable to collect a pattern of light reflected from the illuminated region, the light pattern being indicative of one or more parameters of said via-hole; and, a control system connected to the detection system, the control system comprising a memory utility for storing a predetermined theoretical model comprising data representative of a set of parameters describing via-holes reflected pattern, and a data processing and analyzing utility configured and operable to receive and analyze image data indicative of the detected light pattern and determine one or more parameters of said via-hole.

A lens arrangement is presented. The lens arrangement comprises a first element having a concave reflective surface and defining an optical axis of the lens arrangement, and a second substantially flat and at least partially reflective element spaced-apart from the first element along the optical axis. The second element is configured to allow light passage therethrough and is oriented with respect to the optical axis and the first element such that at a predetermined angle of incidence of an input light beam onto the second element, the input light beam is reflected onto the reflective surface of the first element and reflected therefrom to pass through the second element.

Reflective optical system

An optical system for use in measurements in a sample comprising a light source () operable to produce an incident light beam propagating in a certain direction towards the sample (S) through an illumination channel (IC), a detector unit () for collecting light coming from the sample through a detection channel (DC), and generating data indicative of the collected light, a light directing assembly () operable to direct the incident beam onto a certain location on the sample's plane with a plurality of incident angles, and to direct light returned from the illuminated location to the detector unit (), the light directing assembly () comprising a plurality of beam deflector elements (A-D), at least one of the deflector elements being movable and position of said at least one movable deflector element defining one of the selected incident angles.

Optical system operating with variable angle of incidence

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 metal-containing regions spaced by substantially transparent regions with respect to incident light defining a waveguide. An optical model is provided, which is based on at least some of the features of the structure defined by a certain process of its manufacturing, and on the relation between a range of the wavelengths of incident radiation to be used for measurements and a space size between the two metal-containing regions in the grid cycle, and a skin depth of said metal. 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 is located and spectrophotometric measurements are applied to the measurement area, by illuminating it with incident light of a preset substantially wide wavelength range. A 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 are analyzed and the optical model is optimized until the theoretical data satisfies a predetermined condition. Upon detecting that the predetermined condition is satisfied, said at least one parameter of the structure is calculated.

Method and apparatus for measurements of patterned structures

An apparatus and a method are disclosed for measuring at least one desired parameter of a patterned structure having a plurality of features defined by a certain process of its manufacturing, wherein the structure represents a grid having at least one cycle formed of at least two metal-containing regions spaced by substantially transparent regions with respect to incident light defining a waveguide. The method utilizes an optical model based on at least some of the features of the structure defined by a certain process of its manufacturing, and 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.

The method for controlling layers alignment in a multi-layer sample (), such a semiconductors wafer based on detecting a diffraction efficiency of radiation diffracted from the patterned structures () located one above the other in two different layers of the sample.

An imaging method and system are presented for detecting the topography of a sample surface. Illuminating light is directed to the sample by sequentially passing the illuminating light through a grating and an objective lens arrangement The grating has a pattern formed by spaced-apart transparent regions spaced by non-transparent regions, and is specifically oriented with respect to the optical axis of the objective lens arrangement. Light, specularly reflected from the sample, is collected by the same objective lens arrangement and is directed to an imaging detector through the same grating, thereby enabling creation of an image of the illuminated sample indicative of the topography of the sample surface.

Method and system for measuring the topography of a sample

A method and system are presented for use in controlling a process of material removal from the surface of a patterned structure, by measuring at least one of residue, erosion, dishing and corrosion effects in the structure induced by this process. The structure is imaged utilizing phase modulation of light reflected from the structure, and a phase map of the structure is thereby obtained. This phase map is analyzed and data indicative of light reflective properties of layer stacks of the structure is utilized to determine a phase difference between light reflected from a selected measured site and at least one reference site spaced-apart from the selected site. The phase difference is thus indicative of the measured effect.

Method and system for monitoring a process of material removal from the surface of a patterned structure

An apparatus and a method are disclosed for measuring at least one desired parameter of a patterned structure having a plurality of features defined by a certain process of its manufacturing, wherein the structure represents a grid having at least one cycle formed of at least two metal-containing regions spaced by substantially transparent regions with respect to incident light defining a waveguide. The method utilizes an optical model on at least some of the features of the structure defined by a certain process of its manufacturing, and 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 method and system are presented for measuring in an electrically conductive film of a specific sample including data indicative of a free space response of an RF sensing coil unit to AC voltage applied to the RF sensing coil. The sensing coil is located proximate to the sample at a distance h substantially not exceeding 0.2 r wherein r is the coil radius; an AC voltage in a range from 100 MHz to a few GHz is applied to the sensing coil to cause generation of an eddy current passage through the conductive film; a response of the sensing coil to an effect of the electric current through the conductive film onto a magnetic field of the coil is detected and the measured data indicative of the response is generated. The thickness of the film is determined by utilizing the data indicative of the free space measurements to analyze the measured date. The method thus provides for measuring in conductive films with a sheet resistance Rs in a range from about 0.009 to about 2 Ohm/m .

Method and system for thickness measurements of thin conductive layers

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.

Method and apparatus for monitoring a chemical mechanical planarization process applied to metal-based patterned objects

An optical measurement method and system are presented for imaging two target structures in two parallel layers, respectively, of a sample, to enable determination of a registration between the two target structures along two mutually perpendicular axes of the layer. The sample is illuminated with incident radiation to produce a radiation response of the sample. The radiation response is collected by an objective lens arrangement, and the collected radiation response is split into two spatially separated radiation components. The split radiation components are directed towards at least one imaging plane along different optical channels characterized by optical paths of different lengths, respectively. The two split radiation components are detected in said at least one imaging plane, and two image parts are thereby acquired, each image part containing images of the two target structures. This enables determination of the relative distance between the two target structures.

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Ganei Yehuda, Israel

David Scheiner