Fraunhofer-gesellschaft Zur Foerderung Der Angewandten Forschung E.v.

Philipp Wollmann

Wulf Graehlert

Florian Gruber

Stefan Kaskel

Peter Hartmann

Wulf Grählert

Tobias Baselt

Oliver Throl

Eric Weissenborn

Matthias Leistner

In the method for optical monitoring and/or determination of properties on samples, monochromatic electromagnetic radiation with a predetermined wavelength is sequentially directed from several radiation sources onto a sample influenced by an electronic evaluation unit. The respective intensity specific to the wavelength of the electromagnetic radiation scattered and/or reflected by the sample is detected by at least one detector and fed to the electronic evaluation unit for spectrally resolved evaluation in order to use it to monitor and/or determine properties of the respective sample.

Method for optical monitoring and/or determination of properties of sample

In the arrangement for determining the achievable adhesive strength before forming a connection having material continuity to a surface of a joining partner, a plurality of detectors are present and arranged that are configured for a spatially resolved spectral analysis of electromagnetic radiation within a wavelength interval and are connected to an electronic evaluation unit. They can detect radiation emitted from a broadband radiation source of a reflection incident on the surface of one of the joining partners, and/or after passing through joining partners transparent for the electromagnetic radiation on the detectors. A laterally and temporally homogeneous intensity of the electromagnetic radiation should be observed in this respect. The joining partner is formed from a material that does not 100% absorb the respective electromagnetic radiation and thus a transmission and/or reflection is possible. The electronic evaluation unit is configured such that the measured signals of the detectors detected with spatial resolution and wavelength resolution can be detected within a wavelength interval for individual local points that are arranged on a predefinable surface and measured signals detected at a plurality of positions can be associated with a respective part region of the detected surface (hypercube). A data reduction can be carried out for all measurement signals of the part regions. A statement on a corresponding adhesive strength is achievable using these selected features with a regression model stored in the memory.

Arrangement for determining the achievable adhesive strength before forming a connection having material continuity to a surface of a joining partner

The invention relates to an assembly for determining the permeation rate of a sample for at least one permeate, in particular water vapor, wherein multiple detectors are arranged in a row or in a row and column arrangement for the spatially resolved spectral analysis of electromagnetic radiation within a wavelength interval. The detectors are connected to an electronic evaluation unit and are arranged such that electromagnetic radiation emitted from a broadband radiation source is incident on the detectors either after being reflected by the surface of the sample, by a layer formed on the sample, or by the surface of a layer within the sample, and/or after passing through a sample which is transparent to the electromagnetic radiation. The irradiation is carried out such that a homogeneous intensity of the electromagnetic radiation is maintained on a surface, by means of which the electromagnetic radiation is reflected or through which the radiation is transmitted. The electronic evaluation unit is designed such that the detector measurement signals detected in a spatially- and wavelength-resolved manner can be detected within a wavelength interval for individual location points which are arranged on a specifiable surface of the sample. Each of the measurement signals detected at multiple positions are assigned to a sub-region of the detected surface (hypercube), and a data reduction process is carried out for all of the detected surface sub-region measurement signals which are detected in a wavelength-resolved manner, wherein informative features are selected and can be used together with a previously ascertained regression model, which is stored in an electronic storage device, in order to draw a conclusion regarding a corresponding permeation rate, said regression model being generated using the feature sets, which are obtained analogously, of samples with permeation rates which have been ascertained using another measurement method with a higher degree of measurement precision.

Assembly for determining the permeation rate of a sample

An arrangement for a spatially resolved determination of the specific electrical resistance and/or of the specific electrical conductivity of a sample at different positions, in which a plurality of detectors are configured for a spatially resolved spectral analysis of electromagnetic radiation within a wavelength interval and is incident onto the detectors. A radiation onto a surface takes place with homogeneous intensity. The measurement signals of the detectors detected with spatial resolution and wavelength resolution within a wavelength interval are compared for each detected position with a wavelength-resolved function that are compared by calculation of the propagation of electromagnetic radiation in multilayer systems while using an optical model for a physical description of the examined sample while taking account of the wavelength-dependent progressions of the linear optical refractive indices n and of the coefficients of absorption k of all the materials and/or substances forming the sample that can be approximated by a physical function of a complex refractive index of the conductive material or substance. They are brought to a sufficient overlap with a calibration curve progression by a change of the parameters of the physical function to determine the specific electrical resistance and/or the specific electrical conductivity at different positions with spatial resolution.

Arrangement for spatially resolved determination of the specific electrical resistance and/or the specific electrical conductivity of samples

An arrangement for determining characteristics or parameters of a sample, or a layer formed on or in the sample, has detectors, spatially resolving spectral analysis of electromagnetic radiation within a wavelength interval, provided in rows or in a row and column arrangement, whereby electromagnetic radiation emitted from a broadband radiation source is incident on the detectors after reflecting off, and/or passing through, the sample, or layer formed on or in the sample, upon which is observed a homogeneous intensity of the electromagnetic radiation, and an electronic evaluation unit connected to the detectors compares the spatially-resolved and wavelength-resolved signals detected by the detectors with a theoretical wavelength dependent progression of the respective radiation intensities obtained through simulation or with a progression obtained by calibration on a known sample, in order to obtain information for the measurement position detected, and determine the spatially-resolved distribution of the characteristics or parameters.

Arrangement for determining properties and/or parameters of a sample and/or of at least one film formed on the surface of a sample

The invention relates to a method and to an apparatus for determining the adsorption of a gas at materials. It is the object of the invention to propose possibilities for the determining of the surface properties of materials in which statements can be obtained and very small sample volumes can be examined with sufficient measurement precision, with a reduced technical plant effort and with a reduced time effort. In the invention, a sample of a material is acted on by a gas or gas mixture within a chamber which is not transparent for electromagnetic radiation in the wavelength range between 150 nm and 25 &#x3bc;m. The gas or at least a gas included in a gas mixture is adsorbed at the surface of the sample and in this respect the electromagnetic radiation emitted by the sample as a consequence of the adsorption is detected by at least one optical detector which is sensitive at least in a range of the wavelength range between 150 nm and 25 &#x3bc;m. The measured signals of the detector(s) are in this respect detected with time resolution and are evaluated within a predefinable time interval for determining the surface temperature and/or the adsorption heat of the respective sample varying due to the adsorption.

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Dresden, Germany

Philipp Wollmann