JP2007192552A - Spectral measuring instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spectral measuring instrument capable of efficiently analyzing only a spectrum within an analyzing range. <P>SOLUTION: The spectral measuring instrument 10 includes a measuring light emitting means 16 for emitting spectrum measuring light to irradiate a sample, a measuring light detecting means 18 for acquiring spectra from the respective measuring points in the measuring region within a sample analyzing range, a memory means 22 for storing the spectra of the respective measuring points in relation to the position data of the measuring points and a spectrum calculating means 24 for reading the spectra of the measuring points contained in the analyzing range from the memory means 22, calculating the integrated value or average value of the read spectra of the measuring points and calculating the integrated or average spectrum within the analyzing range. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a spectroscopic measurement apparatus, and more particularly to an improvement in a mechanism for acquiring a spectrum from a set measurement region.

The infrared microscope measures a reflection / transmission spectrum from a specific minute region of a sample as an analysis range. The analysis range is limited by arranging an aperture at the focal position of the objective mirror that collects the reflected / transmitted light from the sample and blocks light from outside the analysis target range. For example, when analyzing dirt on a substrate, extra information from parts other than dirt can be blocked by measuring the aperture shape of the aperture in accordance with the shape of the dirt part (for example, patents). Reference 1).
JP 2001-91453 A

However, since the aperture shape of the aperture used in a general infrared microscope is rectangular, for example, when the analysis range is a complicated shape as shown in FIG. 1, the shape of the aperture cannot be matched to the shape of the analysis range. There was a case. For this reason, there is a problem in that extra light from a part other than the analysis range is detected, which hinders analysis.
In addition, since the amount of light incident on the detector changes when the aperture shape or size of the aperture is changed, the background measurement must be performed with an aperture having the same shape and size as when measuring the sample. Therefore, for example, when measuring a plurality of measurement parts having different shapes, it is necessary to redo the background measurement every time the measurement part is changed, and the measurement takes time.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a spectrometer capable of efficiently analyzing only the spectrum in the analysis range.

In order to achieve the above object, a spectroscopic measurement apparatus according to the present invention includes a measurement light emitting means for emitting measurement light for spectrum measurement to be irradiated on a sample, and analyzing the sample with respect to the sample irradiated with the measurement light. Detecting transmitted light or reflected light from each measurement point in a measurement region including at least a range, and measuring light detection means for measuring the spectrum, and the spectrum at each measurement point detected by the measurement light detection means, Storage means for storing in association with the position information of the measurement point, and a spectrum of the measurement point at least partially included in the analysis range is read from the storage means, and an integrated value or an average value of the read spectrum of the measurement point is obtained. Spectral calculation means for calculating and calculating the integrated or average spectrum of the analysis range.
In the spectroscopic measurement apparatus, an observation image acquisition unit that acquires an observation image of a sample, a display unit that displays the observation image, and the analysis range is specified based on the observation image of the sample displayed on the display unit And an analysis range specifying means.
In the spectroscopic measurement apparatus, the measurement light detection unit includes a multi-element detector provided with a plurality of light-receiving elements, and the spectrum storage unit detects a spectrum detected for each light-receiving element of the multi-element detector. And the position information of the measurement point where the spectrum is detected are preferably stored in association with each other.
In the above-described spectroscopic measurement device, it is preferable that the storage unit stores a background spectrum detected by each light receiving element of the multi-element detector for each light receiving element.

  According to the spectroscopic measurement apparatus of the present invention, the measurement light detection means for acquiring the spectrum from each measurement point in the measurement region including at least the analysis range of the sample, and the position information of the measurement point on the spectrum at each measurement point The storage means for storing in association with and the spectrum of the measurement points that are at least partly included in the analysis range are read from the storage means, the integrated value or average value of the spectrum of the read measurement points is calculated, Since the spectrum calculation means for obtaining the average spectrum is provided, it is possible to extract only the spectrum information from the analysis range and perform an accurate analysis.

A preferred embodiment according to the present invention will be described below with reference to the drawings.
FIG. 2 is a spectroscopic measurement apparatus according to an embodiment of the present invention. The spectroscopic measurement apparatus 10 includes a measurement system 12 that performs spectrum measurement of a specific part of a sample, and a data processing system 14 that performs data processing of spectra measured by the measurement system 12. In this embodiment, the measurement system 12 shows an example of transmission measurement using an infrared microscope, but it can also be applied to reflection measurement or other spectroscopic measurement devices.

  The measurement system 12 includes measurement light emitting means 16 that emits spectrum measurement light, and measurement light detection means 18 that detects reflected light or transmitted light from the sample. The data processing system 14 includes a storage unit 22 that stores a spectrum of each measurement point of the sample detected by the measurement light detection unit 16, and a spectrum calculation unit 24 that calculates an integrated or average spectrum of the analysis range of the sample. Prepare.

The measurement light detection means 18 collects the spectrum of each measurement point in the measurement region including at least the analysis range of the sample. That is, the mapping measurement is performed in the measurement region including the analysis range, and the spectrum of each measurement point in the measurement region is acquired. The spectrum of each measurement point is stored in the storage unit 22 in association with the position information of the measurement point.
In this specification, “analysis range” means a range on which a measurer desires to acquire a transmission or reflection spectrum, and “measurement region” means a region where the apparatus actually measures a spectrum on the sample. The “measurement point” means one small area when the “measurement area” is virtually divided into small areas.
The spectrum calculation unit 24 reads the spectrum of the measurement point at least part of which is included in the analysis range from the storage unit 22, calculates the integrated value or average value of the spectrum, and obtains the integrated or average spectrum of the analysis range. That is, in the spectroscopic measurement apparatus 10 according to the embodiment of the present invention, the spectrum at each measurement point in the measurement range including the analysis range is acquired by mapping measurement, and thereafter, the spectrum calculation unit 24 detects the spectrum from the measurement point within the analysis range. Only spectra are collected, and the average spectrum in the analysis range is obtained numerically from these spectra. Since the average spectrum of the analysis range is obtained numerically in this way, only the spectrum from the analysis range can be efficiently extracted even if the analysis range has a complicated shape.

In order to set the analysis range of the sample, the measurement system 12 includes an observation image acquisition unit 20 that acquires an observation image of the measurement system sample, and the data processing system 14 includes a display unit 26 that displays the observation image, and a display unit 26. And an analysis range specifying means 28 for specifying the analysis range of the sample based on the displayed observation image. The range specifying means 28 can easily specify the analysis range while viewing the observation image of the sample displayed on the display means 26.
The above is the schematic configuration of the present embodiment, and more detailed description of each configuration will be given below.

Measurement system 12
The measurement system 12 of the present embodiment performs infrared spectrum measurement in a minute region of a sample, and includes a measurement light emitting unit 16 that emits measurement light, and a microscope unit that collects light from the minute region of the sample ( Objective mirror 36), measurement light detection means 18 for detecting light collected by the microscope means, and observation image acquisition means 20 for acquiring an observation image of the sample.
The measurement light emitting means 16 includes an infrared light source 30 and a spectroscope 32 such as a Michelson interferometer. Infrared light emitted from the infrared light source 30 passes through the spectroscope 32 and is condensed on a specific minute part of the sample by an objective mirror 34 constituted by a Cassegrain mirror or the like. The transmitted light from the sample is condensed by an objective mirror 36 (microscopic means) constituted by a Cassegrain mirror or the like, and detected by the measurement light detection means 18 through the aperture 38 and the condenser mirror 40. Note that the aperture 38 may have a shape and a size corresponding to the light receiving surface of the measurement light detection means 18.

  In the present embodiment, the measurement light detection means 18 includes a multi-element detector in which a plurality of light receiving elements are arranged in a one-dimensional or two-dimensional manner. Each light receiving element corresponds to each measurement point of the sample, and transmitted light from the corresponding measurement point is detected for each light receiving element and sent to the data processing system 14. The spectrum information detected by each light receiving element is stored in the storage means 22 for each light receiving element in association with the spectrum and the position information of the measurement point from which the spectrum was acquired. By using a multi-element detector with high spatial resolution, the size of each measurement point can be made minute, so that it is possible to cope with an analysis range of a complicated shape.

  The observation image acquisition means 20 includes a visible light source 42 that irradiates observation light onto the sample surface, and an image detector 44 that detects observation light reflected or transmitted from the sample and acquires an observation image of the sample surface. Prepare. The light emitted from the visible light source 42 is condensed on a specific part of the sample by the objective mirror 34 via the reflecting mirror 46. The transmitted light from the sample is collected by the objective mirror 36 and detected by the image detector 44 via the reflecting mirror 48 and the condenser lens 50. The image detector 44 is composed of a CCD image detector or the like. The reflecting mirror 46 and the reflecting mirror 48 are configured to be inserted / retracted on the optical path, and are retracted from the optical path at the time of spectrum measurement. An image detection signal from the image detector 44 is sent to the data processing system 14 and stored in the storage means 22. The observation image stored in the storage means 22 is displayed on the display means 26 and used for designating the analysis target range.

  The sample is placed on a stage 52 configured to be movable in the XY directions, and the measurement region on the sample can be changed by driving the stage 52. The driving of the stage 52 is controlled by the measurement position control means 54. As for the control of the measurement position, as described in Japanese Patent Application Laid-Open No. 2005-127908 etc., a scan mirror capable of changing the orientation of the reflecting surface is provided on the optical path from the sample to the aperture 38, and measurement is performed. The position of the measurement point received by the light detection means 18 may be changed. In this case, the measurement position control means 54 controls the direction of the reflection surface of the scan mirror.

Data processing system 14
In the data processing system 14, processing of the detection signal from the measurement light detection means 18, detection signal from the observation image acquisition means 20, control of the measurement system 12, and the like are performed. The data processing system 14 includes a computer 56 and display means 26 such as a display. In the present embodiment, the storage unit 22 is configured by a hard disk, a memory, and the like of the computer 56, and the spectrum calculation unit 24 is realized by a program executed by the computer 56.

  The analysis range specifying means 28 includes an input unit 58 connected to a computer 56 such as a mouse and a keyboard, and a range setting unit 60 that sets an analysis range by input from the input unit 58. For example, the analysis range is set as follows. Move the pointer on the display with the mouse, and specify the line that surrounds the analysis target area on the observation image of the sample displayed on the display with the pointer (for example, specify several points on the line and surround the analysis range. Etc.). The range setting unit 60 obtains a condition (for example, a condition imposed on the position information of the measurement point) that defines the analysis range based on the input from the input unit 58 and stores it in the storage unit.

  The spectrum calculation unit 24 determines whether or not the measurement point belongs to the analysis target range from the position information of the measurement point stored in the storage unit 22 and the conditions defining the analysis range. Then, the spectrum of the measurement point belonging to the analysis target range is read from the storage means 22, and the integrated value or average value thereof is calculated to obtain the integrated or average spectrum.

<Spectrum measurement>
Hereinafter, spectrum measurement using the spectrometer of the present embodiment will be described along the measurement procedure.
Setting of analysis range Here, a description will be given on the assumption that a substrate is used as a sample and a component of dirt adhering to the substrate is analyzed. The sample image acquired by the sample image acquisition unit is displayed on the display unit as shown in FIG. Here, the hatched portion in FIG. 3 indicates a dirty portion attached to the substrate.
The user operates the mouse or the like to move the pointer on the display means and designates a desired analysis range (a range surrounded by a dotted line in FIG. 4) as shown in FIG. Here, an example in which three or more points are specified and a range surrounded by a polygon connecting the specified points (black circles in FIG. 4) is set as the analysis range is shown. However, the method for specifying the analysis range is not limited to the above method, and other methods may be used (for example, see Patent Document 1). For example, in general, the analysis range is often different in color, brightness, and the like from other regions when observed with visible light. Using this, when a point is specified, a method of automatically analyzing a range having substantially the same color, lightness, etc. as that point and making it an analysis range may be used. Thus, since the analysis range is set while viewing the sample image, the analysis can be easily performed.

Acquisition of Spectrum When the analysis range is specified as described above, mapping measurement is performed using the region including the analysis range as a measurement region (a portion surrounded by a one-dot chain line in FIG. 4) as shown in FIG. Here, a case where a multi-element detector in which light receiving elements are arranged in a line (linear array detector) will be described.
FIGS. 5A to 5C are explanatory diagrams in that case. In FIG. 5A, each small square is a measurement point corresponding to each light receiving element of the one-dimensional multi-element detector, and mapping measurement in the direction in which the light receiving elements are arranged is performed once using the function of the detector itself. To be done. Then, as shown in FIGS. 5A to 5C, the measurement points of the detector are successively moved in a direction orthogonal to the arrangement direction of the light receiving elements, and a spectrum is acquired from each measurement point in the measurement region. Note that the dotted lines in FIGS. 4B and 4C indicate measurement points that have already been measured. The acquired spectrum of each measurement point is stored in the storage unit together with the position information of the measurement point. Note that the aperture may have a shape and a size corresponding to the light receiving surface of the measurement light detecting means.

Computation of spectrum of analysis target range When mapping measurement of the measurement area is completed as described above, the spectrum of each measurement point (small square portion in FIG. 6) of the measurement area is associated with the position information in the storage means. Remembered. In the spectrum calculation means, based on the position information of the measurement points and the information of the analysis range, the measurement points completely included in the analysis region (the hatched portion in FIG. 6) are read from the storage means, and their average value ( (Or integrated value). Thus, according to the spectroscopic measurement apparatus of the present embodiment, only the spectrum in the analysis range can be easily extracted even if the shape of the range in which the spectrum is collected is complicated.
In the example of FIG. 6, only the spectrum of the measurement points completely included in the analysis range is extracted and the calculation is performed. However, as shown in FIG. 7, at least a part of the measurement is included in the analysis range. The calculation may also be performed by taking out points (shaded portions in FIG. 7).

<Background measurement>
The background spectrum may be acquired in advance with the same aperture as that used for measurement, that is, an aperture having a shape and size corresponding to the light receiving surface of the measurement light detection means. For example, when a one-dimensional multi-element detector is used, measurement may be performed with a slit shape having a size and shape that match the aperture shape of the aperture with the shape of the light receiving portion of the detector. The background spectrum is stored in the storage means for each light receiving element. Correction of the spectrum detected by each light receiving element is performed using the background spectrum measured in advance by each light receiving element. That is, according to the spectroscopic measurement apparatus according to the embodiment of the present invention, the background measurement may be performed on a certain rectangular aperture and does not depend on the shape of the analysis range. Therefore, measurement can be continuously performed even when measuring spectra in a plurality of analysis ranges having different shapes.

Explanatory diagram showing the relationship between analysis range and aperture 1 is a schematic configuration diagram of a spectrometer according to an embodiment of the present invention. Schematic diagram of the observation image of the sample Illustration of setting the analysis range Explanatory drawing of measurement area mapping measurement Illustration of average spectrum calculation Illustration of average spectrum calculation

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Spectrometer 12 Measurement system 14 Data processing system 16 Measurement light emission means 18 Measurement light detection means 20 Observation image acquisition means 22 Storage means 24 Spectrum calculation means 26 Display means 28 Analysis range designation means

Claims (4)

A measurement light emitting means for emitting measurement light for spectrum measurement to irradiate the sample;
Measuring light detection means for detecting the transmitted light or reflected light from each measurement point in the measurement region including at least the analysis range of the sample, and measuring the spectrum, with respect to the sample irradiated with the measurement light,
Storage means for storing a spectrum at each measurement point detected by the measurement light detection means in association with position information of the measurement point;
Spectrum calculation for reading the spectrum of the measurement point at least partially included in the analysis range from the storage means, calculating the integrated value or average value of the spectrum of the read measurement point, and obtaining the integrated or average spectrum of the analysis range And a spectroscopic measurement device. The spectroscopic measurement device according to claim 1,
An observation image acquisition means for acquiring an observation image of the sample;
Display means for displaying the observed image;
A spectroscopic measurement apparatus comprising: an analysis range designating unit that designates the analysis range based on an observation image of the sample displayed on the display unit. The spectrometer according to claim 1 or 2,
The measurement light detection means includes a multi-element detector provided with a plurality of light receiving elements,
The spectrum storage device stores, for each light receiving element of the multi-element detector, the detected spectrum and the position information of the measurement point where the spectrum is detected in association with each other. The spectrometer according to claim 3,
The spectroscopic measurement apparatus, wherein the storage means stores a background spectrum detected by each light receiving element of the multi-element detector for each light receiving element.

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