JP4634413B2 - measuring device - Google Patents

Description

  The present invention relates to a measurement apparatus for measuring a component of a sample by irradiating the sample with a laser beam and converting the components contained in the sample into plasma and analyzing the sample. In particular, the sample is measured at low cost, quickly, and with high accuracy. It relates to a possible measuring device.

  In recent years, environmental pollution due to industrial waste has become serious, and there is an increasing demand for the industry to regulate the use of hazardous substances. For example, in Europe, the RoHS directive restricts the use of certain hazardous substances (lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyl, polybrominated diphenyl ether) in electrical and electronic equipment, and the ELV directive limits the use of automobiles. Use of harmful substances (cadmium, lead, mercury, hexavalent chromium) in parts is restricted.

In response to such social circumstances, measurement and inspection of harmful substances contained in parts are being carried out at the manufacturing site of electrical appliances and the like. As methods for measuring the presence or absence of harmful substances, various methods such as inductively coupled plasma analysis, gas chromatography mass spectrometry, and fluorescent X-ray analysis are known. In particular, X-ray fluorescence analysis is widely used because it can measure the content of harmful substances in a sample without destroying the sample.
JP 2003-139750 A JP 2006-119108 A

  However, the conventional measuring method has problems that it takes time to measure and the cost is high. In particular, among the conventional measurement methods described above, the inductively coupled plasma analysis method, the gas chromatograph method, and the like require cost and time because the measurement object must be destroyed. In addition, the X-ray fluorescence analysis method does not require destruction of the measurement object. However, since X-rays are used, the measurement object must be moved to the management area, and an administrator is required. And time consuming. Therefore, for example, it is virtually impossible to measure all the products shipped from the factory or all the parts received in the factory.

  Furthermore, the fluorescent X-ray analysis method has a problem that the measurement accuracy is low when the measurement target is smaller than the X-ray irradiation region or when the thickness is small. As a result, the fluorescent X-ray analysis method has a disadvantage that it cannot inspect a thin film (plating) and a minute portion.

  The present invention has been made to solve the above problems, and an object thereof is to provide a measuring apparatus capable of measuring a sample at low cost, quickly, and with high accuracy.

The measuring apparatus according to claim 1, which measures a component of a sample by irradiating the sample with a laser beam and converting the component contained in the sample into plasma and analyzing the laser beam, and outputs the laser beam Out of the output light , the optical system for condensing and irradiating the sample with the laser light output from the laser light output means, and the optical system out of the plasma light emitted from the plasma generated when the sample receives the laser light Measuring means for spectrally measuring plasma light radiated obliquely or perpendicularly to the optical path of laser light incident on the sample after passing through the laser , and laser by the laser light output means after a predetermined time has elapsed from the light output start timing control means for controlling the measurement time zone of the plasma light by the measuring means to start measurement of plasma light by the measuring means The a measured by the measuring means spectrum, based on the characteristic wavelength of the measurement target component, the content of the measured value acquisition means for acquiring content measurement value corresponding to the content of the measurement target component in the sample, wherein A counting means for counting the number of times of irradiation of the laser light output from the laser light output means, a relationship between the number of times of irradiation of the laser light and the depth of the hole formed in the sample by the irradiation of the laser light is stored. 1 storage means, second storage means for storing the content rate measurement value acquired by the content rate measurement value acquisition means, content rate measurement value stored in the second storage means, and content rate measurement value acquisition Determining means for determining whether the difference from the content measurement value newly acquired by the means is a predetermined value or more before performing the next irradiation of the laser beam on the sample, and the difference by the determining means When it is determined that the value is equal to or greater than a predetermined value, the number of irradiations counted by the counting unit, the number of irradiations of the laser beam stored in the first storage unit, and the laser beam irradiation are formed on the sample. A thickness calculation means for calculating the thickness of the measurement target component in the sample based on the relationship with the depth of the hole to be measured, and a measurement result for outputting the measurement target component thickness calculated by the thickness calculation means as the measurement result Output means.

The measurement apparatus according to claim 2 is the measurement apparatus according to claim 1 , further comprising an irradiation position moving unit that moves an irradiation position of the laser beam that condenses and irradiates the sample relative to the sample. The result output means outputs a measurement result based on the irradiation position of the laser light moved by the irradiation position moving means and the content rate measurement value acquired by irradiating the laser light at the irradiation position.

Measuring device according to claim 3, wherein, in the measuring apparatus according to claim 2, wherein said measurement result output means, the average of the content of the measurement values that are obtained by irradiating the laser light into a plurality of the irradiation position in the sample The value is output as the measurement result.

The measurement apparatus according to claim 4 is the measurement apparatus according to any one of claims 1 to 3 , wherein the measurement result output unit further irradiates a crater formed on the sample by irradiation with the laser light. Then, an average value of a plurality of content rate measurement values acquired by the plurality of irradiations is output as a measurement result.

The measuring apparatus according to claim 5 is the measuring apparatus according to claim 4 , further comprising a counting unit that counts the number of times of irradiation of the laser beam output from the laser beam output unit, and the measurement result output unit includes the counting unit. When the number of times of irradiation counted by the above is equal to or greater than a predetermined number, the average value of each content rate measurement value acquired is output as a measurement result.

The measuring apparatus according to claim 6 is the measuring apparatus according to any one of claims 1 to 5 , wherein the sample is located at a part off the primary plume that is a central part of plasma generated by irradiation with the laser beam. Light receiving means for receiving plasma light emitted from the plasma in a focused manner is provided, and the measuring means separates the plasma light received by the light receiving means and measures the spectrum of the plasma light.

According to the measuring apparatus of the first aspect, the laser beam is output by the laser beam output unit, and the laser beam output from the laser beam output unit is condensed and irradiated on the sample by the optical system. The measurement means separates the plasma light emitted from the plasma generated when the sample receives the laser light, and measures the spectrum of the plasma light. The content rate measurement value corresponding to the content rate of the measurement target component in the sample is acquired by the content rate measurement value acquisition unit based on the spectrum measured by the measurement unit and the characteristic wavelength of the measurement target component. The measurement result output means outputs a measurement result based on the content rate measurement value acquired by the content rate measurement value acquisition means. Therefore, compared with the conventional fluorescent X-ray analysis method, there is an effect that a sample can be measured promptly at low cost without requiring an administrator or a management area. Furthermore, the laser beam can be irradiated to a minute part, and even when the sample is thin, it can be irradiated and its spectrum can be measured. For example, plating, solder joints on a substrate, etc. Even if it is a thin film and a very small specific region, there is an effect that it can be measured with high accuracy.
Further, the measurement time zone of the plasma light by the measuring means is controlled by the timing control means. The timing control means starts the measurement of the plasma light by the measurement means after a predetermined time has elapsed from the start of the laser light output by the laser light output means, so the plasma light is measured at an appropriate timing according to the time-dependent change of the plasma light. Therefore, there is an effect that measurement can be performed with high accuracy.
Further, the measurement means divides the plasma light emitted in an oblique direction or a vertical direction with respect to the optical path of the laser light incident on the sample through the optical system, and measures the spectrum of the plasma light. When laser light applied to the sample is reflected from the sample, most of the laser light is reflected in the same direction as the optical path of the laser light incident on the sample. Therefore, plasma light emitted obliquely or perpendicularly to the optical path is reflected. By measuring, it can suppress that the laser beam reflected in a sample is measured by a measurement means, and there exists an effect that it can measure with high precision.
The counting means counts the number of times the laser light is emitted from the laser light output means. The relationship between the number of times of laser light irradiation and the depth of the hole formed in the sample by the laser light irradiation is stored in the first storage means, and the content rate measurement value acquired by the content rate measurement value acquisition means is Stored in the second storage means. The determination unit determines whether the difference between the content rate measurement value stored in the second storage unit and the content rate measurement value newly acquired by the content rate measurement value acquisition unit is equal to or greater than a predetermined value. When the determination means determines that the difference is greater than or equal to a predetermined value, the thickness calculation means counts the number of irradiations counted by the counting means and the number of times the laser light is stored in the first storage means, and the laser light Based on the relationship with the depth of the hole formed in the sample by irradiation, the thickness of the measurement target component in the sample is calculated. Therefore, there is an effect that the thickness of the sample can be measured.

According to the measuring apparatus of claim 2 , in addition to the effect of the measuring apparatus of claim 1 , the irradiation position of the laser beam focused and irradiated on the sample is moved relative to the sample by the irradiation position moving means. Therefore, it is possible to easily measure the content measurement values at a plurality of locations in the sample. Further, the measurement result output means outputs the measurement result based on the irradiation position of the laser light moved by the irradiation position moving means and the content rate measurement value acquired by irradiating the laser light at the irradiation position. The user can know the distribution of the measured content rate in the sample.

According to the measuring apparatus of claim 3 , in addition to the effect produced by the measuring apparatus of claim 2, each content rate measurement value obtained by irradiating the sample with laser light at a plurality of irradiation positions by the measurement result output means Since the average value of is output as a measurement result, there is an effect that the user can know the average value of each content rate measurement value measured at a plurality of locations of the sample.

According to the measuring apparatus of claim 4 , in addition to the effect of the measuring apparatus according to any of claims 1 to 3 , the measurement result output means further applies laser to the crater formed by laser light irradiation on the sample. Since the average value of a plurality of measured content values obtained by irradiating light is obtained as a measurement result, the user can measure each content rate in the depth direction of the same part of the sample. There is an effect that the average value can be known.

According to the measurement apparatus of the fifth aspect , in addition to the effect produced by the measurement apparatus according to the fourth aspect, the number of times of irradiation of the laser beam output from the laser beam output unit is counted by the counting unit. The measurement result output means outputs the average value of each content rate measurement value acquired when the number of irradiations counted by the counting means is a predetermined number or more, as a measurement result. Therefore, even if the properties in the vicinity of the sample surface have changed due to oxidation or the like, the sample with the changed properties is shaved by a predetermined number of laser irradiations, so the measured content of the sample with the changed properties becomes the average value. Inclusion is suppressed, and there is an effect that the user can know the average value of the measured content rate of the sample with higher accuracy.

According to the measurement apparatus of claim 6 , in addition to the effect of the measurement apparatus according to any one of claims 1 to 5 , the sample is received at the central portion of the plasma generated by the irradiation of the laser beam by the light receiving means. A portion off the primary plume is focused, and plasma light emitted from the plasma is received. The plasma light received by the light receiving means is dispersed by the measuring means, and the spectrum of the plasma light is measured. Rather than receiving the plasma light focused on the primary plume, the measurement noise measured by the measurement means can be suppressed by receiving the plasma light focused on the part off the primary plume. There is an effect that measurement can be performed with high accuracy.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram showing a schematic configuration of a measuring apparatus 1 according to the first embodiment of the present invention.

  The measurement apparatus 1 is an emission analysis apparatus that utilizes a laser microprobe analyzer (LMA) and contains a plurality of types of harmful substances (hereinafter referred to as measurement target components) contained in the sample 3. It is a measuring device that can automatically measure the rate. In addition, the measuring apparatus 1 and the measuring apparatus 31 (refer FIG. 11) mentioned later measure an electrical product or the components of a motor vehicle as the sample 3, and lead (Pb), mercury (as a measuring object component) It is assumed that the content of Hg), cadmium (Cd), chromium (Cr), and bromine (Br) is measured.

  As shown in FIG. 1, a measuring apparatus 1 includes a laser oscillator 2 that outputs laser light, an objective lens 4 that focuses and irradiates a sample 3 with laser light output from the laser oscillator 2, and a sample that receives the laser light. A condenser lens 6 that condenses the plasma light emitted from the plasma 5 generated by 3, a spectrometer 8 that measures the plasma light collected by the condenser lens 6, and outputs the spectrum to the computer 10; The measurement result of the sample 3 is calculated and displayed based on the gate controller 9 that controls the timing at which the laser oscillator 2 outputs the laser light and the timing at which the spectrometer 8 measures the plasma light, and the spectrum input from the spectrometer 8. And a computer 10 that performs processing.

  When a laser control signal is input from the gate controller 9 described later, the laser oscillator 2 outputs, for example, YAG laser light having a laser energy of 30 mJ and a pulse width of 10 ns. The objective lens 4 is a lens for condensing the laser beam output from the laser oscillator 2 and irradiating the sample 3, and is configured so that the irradiation diameter of the laser beam is about 1 mm in the sample 3. Yes.

  When the sample 3 receives the laser light (condensed irradiation) collected by the objective lens 4, a part of the sample 3 is excited and evaporated to generate plasma 5. The central portion of the generated plasma 5 is particularly called a primary plume 5a. The recombination of the plasma 5 starts with the end of the laser light irradiation, and the constituent elements of the sample 3 become excited atoms for several to several tens of microseconds, and the excited state atoms transition to the lower level. Sometimes it emits plasma light proportional to the number of atoms. That is, each atom emits plasma light having a specific wavelength. Therefore, by measuring the intensity of the plasma light emitted from the plasma 5 at a predetermined wavelength, the content of the target component to be measured is increased. It can be obtained with accuracy.

  The condensing lens 6 is a lens for condensing the plasma light of the plasma 5 generated by the sample 3 and inputting it to the spectroscope 8. The condensing lens 6 is focused on a portion off the primary plume 5a. Rather than focusing the primary plume 5a and condensing the plasma light, focusing the plasma light on the part out of the primary plume 5a suppresses measurement noise measured by the spectroscope 8. Therefore, it is possible to measure with high accuracy. When measuring plasma light radiated in an oblique direction with respect to the optical path L, it is difficult to be influenced by the shape of the sample 3 (for example, unevenness), and the measurement should be performed with high accuracy regardless of the shape of the sample 3. Can do. Thus, focusing on a specific position in the plasma 5 and measuring the plasma light is referred to as a spatially resolved photometric method.

  The condensing lens 6 condenses plasma light emitted in an oblique direction or a vertical direction with respect to the optical path L of the laser light that passes through the objective lens 4 and enters the sample 3, and causes the spectroscope 8 to condense. You are typing. When the laser light applied to the sample 3 is reflected by the sample 3, most of the laser light is reflected in the direction coaxial with the optical path L of the laser light incident on the sample 3 (toward the objective lens 4). By measuring the plasma light radiated obliquely or vertically, it is possible to suppress the laser light reflected from the sample 3 from being measured by the spectroscope 8 and to measure with high accuracy.

  The spectroscope 8 measures the plasma light collected by the condenser lens 6 when a measurement control signal is input from the gate controller 9 described later, and generates a spectrum of the measured plasma light (see FIG. Step S27 of 8). As shown in FIG. 3A, the spectrum is obtained by arranging the spectral line intensities for each wavelength in order of wavelength. The spectroscope 8 outputs the generated spectrum to the computer 10. In the computer 10, the value of the spectral line intensity of the spectrum input from the spectroscope 8 is not directly used for the calculation, but is used for the calculation after removing the offset component generated by the measurement. In general, the minimum value output from the measuring instrument is set so that zero is used as a reference, but the reference varies depending on the measurement conditions and the change over time of the measuring instrument. The reference (zero) fluctuation amount is referred to as an offset component. In the present embodiment, the value obtained by removing the offset component from the value of the average spectrum (see FIG. 8) is used as the spectral line intensity of each measurement target component. That is, the spectral line intensity of lead (Pb) in the average spectrum shown in FIG. u. ]. Hereinafter, the spectral line intensity will be described as a value excluding the offset component.

  When a trigger signal is input from the computer 10 to be described later, the gate controller 9 outputs a laser control signal for instructing the start of laser beam output to the laser oscillator 2, and also measures a measurement time zone for measurement of plasma light (measurement start) A measurement control signal defining the timing and measurement time width is output to the spectrometer 8. The gate controller 9 has a delay circuit 9 a for synchronizing the laser light irradiation and the plasma light measurement, and outputs a laser control signal to the laser oscillator 2 when the trigger signal is input from the computer 10. However, the delay circuit 9a outputs the measurement control signal to the spectroscope 8 with a predetermined time delay from the laser control signal. Therefore, with respect to the plasma light generated by the laser light irradiation and changing with time, the spectroscope 8 can start measuring the plasma light with a delay time appropriately set for the change (see FIG. 5). .

  Next, the computer 10 and various devices connected to the computer 10 will be described with reference to FIG. FIG. 2 is a block diagram illustrating a schematic configuration of the computer 10. As shown in FIG. 2, the computer 10 includes a CPU 11, a ROM 12, a RAM 13, an HDD 14, an input device 15, a display device 16, and an interface 17 (I for inputting a spectrum output from the spectrometer 8. / F 17) and an interface 18 (I / F 18) for outputting a trigger signal to the gate controller 9, and these are connected to each other via a bus line 19.

  The CPU 11 controls each unit connected to the bus line 19 according to fixed values and programs stored in the ROM 12 and RAM 13. The ROM 12 is a non-rewritable memory in which a control program executed by the CPU 11 is stored. The RAM 13 is a rewritable volatile memory, and is a memory for temporarily storing data and programs necessary for various processes executed by the CPU 11. The spectrum output from the spectroscope 8 and input to the computer 10 is temporarily stored in the RAM 13 (the process of S24 in FIG. 8).

  The HDD 14 is a hard disk and is a rewritable nonvolatile memory. The data stored in the HDD 14 is retained even after the computer 10 is turned off. The programs shown in the flowcharts of FIGS. 7, 8, 10, and 13 to be described later are stored in the HDD.

  In the HDD 14, calibration data memory 14 a in which calibration data for acquiring the content of each measurement target component is stored from the spectral line intensity of the spectrum measured by the spectroscope 8, and each calculated as a measurement result is stored. A threshold memory 14b storing a threshold for evaluating the accuracy of the content rate of the measurement target component, and a consumption storing the amount (depth) of the sample 3 that is consumed as a plasma by condensing irradiation of laser light. An amount memory 14c and a measurement result memory 14d for storing the content of each measurement target component calculated as the measurement result or the thickness of the sample consumed by the measurement are provided.

  The calibration data memory 14a is a memory in which calibration data for acquiring the content rate of each measurement target component from the spectral line intensity of the spectrum measured by the spectrometer 8 is stored. In the calibration data memory 14a, lead calibration data 14a1, mercury calibration data 14a2, cadmium calibration data 14a3, chromium calibration data 14a4, and bromine calibration data 14a5 are provided. The lead calibration data 14a1 stores calibration data (see FIG. 3 (b)) showing the relationship between the spectral line intensity and content of lead (Pb) obtained experimentally in advance. Similarly, in the mercury calibration data 14a2, calibration data indicating the relationship between the spectral line intensity and content of mercury (Hg) obtained experimentally in advance is obtained in the cadmium calibration data 14a3 in advance. The calibration data showing the relationship between the spectral line intensity and the content of cadmium (Cd) is the chromium calibration data 14a4. The relationship between the spectral line intensity and the content of chromium (Cr) obtained experimentally in advance The calibration data to be shown is stored in the bromine calibration data 14a5, respectively. The calibration data showing the relationship between the spectral line intensity and the content of bromine (Br) obtained experimentally in advance is stored.

  Here, each calibration data stored in the calibration data memory 14a will be described with reference to FIG. FIG. 3A is a graph showing an example of the contents of an average spectrum created by the computer 10 when solder is measured. The spectral line intensity at each wavelength in the X-axis direction and at the respective wavelengths in the Y-axis direction. Is marked. FIG.3 (b) is a graph which shows an example of the content of the calibration data which shows the relationship between the spectral line intensity and content rate of lead (Pb) which were experimentally obtained in advance, and the content rate is in the X-axis direction. The spectral line intensity is marked in the Y-axis direction.

  When the spectroscope 8 measures the plasma light of the plasma 5 generated by the sample 3, it generates a spectrum of the measured plasma light and outputs it to the computer 10. The computer 10 creates the average spectrum shown in FIG. 3A based on the plurality of spectra input from the spectroscope 8 (processing of S27 in FIG. 8). The wavelength of the plasma light emitted from the atoms is unique to each atom, and the plasma light emitted from the plasma 5 generated by the sample 3 includes the plasma light emitted from each atom contained in the sample 3. include. It is possible to determine whether or not the sample 3 contains the measurement target component by examining whether or not the plasma light having a specific wavelength emitted by each atom of the measurement target component is emitted from the plasma 5 generated by the sample 3. .

  FIG. 3B is a graph showing an example of calibration data indicating the relationship between the spectral line intensity and content of lead (Pb) obtained experimentally in advance. In the present embodiment, the spectral line intensity of the measurement target component whose content is known in advance is experimentally obtained, and the relationship between the spectral line intensity of the measurement target component and the content as shown in FIG. 3B is shown. Calibration data is created. Since the spectral line intensity emitted by each atom is proportional to the content of each atom contained in the sample 3 to be measured, by comparing the spectral line intensity emitted from the sample 3 with the calibration curve data, The computer 10 can acquire the content rate of the measurement target component of the sample 3 (processing of S28 in FIG. 8). The calibration data 14a1 to 14a5 of the calibration data memory 14a stores calibration data of each measurement target component.

  Returning to the description of FIG. The threshold memory 14b is a memory that stores a threshold for evaluating the accuracy of the content ratio of each measurement target component calculated as a measurement result (see FIG. 4A). When obtaining the content of each measurement target component contained in the sample 3, in this embodiment, the average value of the content of each measurement target component measured a plurality of times (for example, 10 times) is used as a measurement result (FIG. 7). Process of S7). By making the average value of each content rate measured a plurality of times as a measurement result, the influence of measurement errors can be reduced.

  Moreover, the standard deviation of the content rate measured several times is calculated, The value which divided the standard deviation by the average value of the content rate used for calculation of a standard deviation is made into the accuracy judgment value. If the accuracy determination value exceeds the predetermined value, the measurement result is unknown because the measurement accuracy is low (processing of S6 in FIG. 7). Measured according to the type of sample (metal or resin, etc.), the type of measurement target component to be measured, the influence of components other than the measurement target component to be measured, the accuracy of the laser oscillator 2 and the accuracy of the spectrometer 8 When the accuracy of the result cannot be obtained, the reliability of measurement can be improved by making the measurement result unknown.

  In the threshold memory 14b, a threshold of an accuracy determination value used for evaluating the measurement result is stored as an accuracy threshold. For example, when the accuracy threshold is set to 5%, if the accuracy determination value of the content rate of a certain measurement target component obtained by measurement is larger than 5%, the measurement result of the measurement target component is unclear.

Anti Worn amount memory 14c is a memory amount of the sample 3 to be depleted in plasma by condensing laser light irradiation (depth) is stored. When the sample 3 receives the focused laser beam irradiation, a part of the sample 3 is excited to generate plasma 5, and a crater-like hole is formed in the sample 3 irradiated with the laser beam focused irradiation. Is done. The consumption Worn amount memory 14c, as shown in FIG. 4 (b), consumption is the depth of one crater-like hole formed by condensing laser light irradiation is stored. This consumption amount is a value obtained experimentally in advance. For example, in the measuring apparatus 1 (or measuring apparatus 31 described later), when laser light is focused and irradiated once on the solder, a crater having a depth of 50 nm is formed. As described above, by setting the laser beam irradiation diameter on the sample 3 to about 1 mm in diameter, a crater having such a stable depth can be formed.

  The measurement result memory 14d is a memory for storing the content rate of each measurement target component calculated as the measurement result or the thickness of the sample consumed by the measurement. The measurement result memory 14d includes a lead content measurement result 14d1, a mercury content measurement result 14d2, a cadmium content measurement result 14d3, a chromium content measurement result 14d4, a bromine content measurement result 14d5, and a thickness measurement. Result 14d6 is provided.

  The lead content rate measurement result 14d1 is a memory for storing the lead content rate among the content rates of the respective components to be measured, which are measurement results measured for the sample 3. Similarly, the mercury content measurement result 14d2 includes mercury content, the cadmium content measurement result 14d3 includes cadmium content, and the chromium content measurement result 14d4 includes chromium content. In the rate measurement result 14d5, the bromine content is stored. The thickness measurement result 14d6 stores the thickness of the consumed sample 3 calculated when the thickness measurement process (see FIG. 10) is performed.

  The input device 15 is used when the computer 10 is managed or a command (command) for outputting a trigger signal to the gate controller 9 is input, and includes, for example, a keyboard and a mouse. The display device 16 displays characters, images, and the like in order to visually confirm the processing content executed by the computer 10 and the spectrum input from the spectrometer 8. And the thickness of the sample 3 when the thickness measurement process (see FIG. 10) is performed. The display device 16 is configured by, for example, a CRT display or a liquid crystal display.

  The I / F 17 connects the computer 10 and the spectroscope 8 and inputs a spectrum output from the spectroscope 8. The I / F 18 connects the computer 10 and the gate controller 9. When a command (command) for outputting a trigger signal is input from the input device 15, the computer 10 inputs the trigger signal to the gate controller 9 at a predetermined timing via the I / F 18. When the trigger signal is input, the gate controller 9 outputs a laser control signal and a measurement control signal, so that measurement of the sample 3 is started.

  Next, with reference to FIG. 5, the measurement time zone (measurement start timing and measurement time width) of the plasma light measured by the spectrometer 8 will be described. Here, description will be made assuming that the sample 3 uses solder. FIG. 5A is a graph showing an example of the relationship between the emission intensity of the plasma light emitted from the solder and the time. The laser light is focused and irradiated on the solder, and the plasma light is emitted from the plasma 5. The time is shown in the X-axis direction and the emission intensity of the plasma light is shown in the Y-axis direction with reference to the moment.

  FIG. 5B is a graph showing an example of measurement results obtained by measuring the spectral line intensity of lead (Pb) contained in the solder without providing a delay time Td described later. FIG. 5C is a graph showing an example of a measurement result obtained by measuring a spectral line intensity of lead (Pb) contained in the same solder as that in FIG. 5B by providing a delay time Td described later of 0.4 μsec. It is. FIG. 5B and FIG. 5C show the wavelength in the X-axis direction and the spectral line intensity at each wavelength in the Y-axis direction.

  As shown in FIG. 5A, the emission intensity of the plasma light emitted from the plasma 5 is the strongest at the moment when the plasma light is emitted from the plasma 5, and thereafter falls with a steep gradient. The emission intensity gradually decreases while increasing and decreasing in the middle of the decrease. In the present embodiment, the measurement start time is defined as the moment when the emission intensity of the plasma light is lowered with a steep slope and the rise is started (plasma light is emitted from the plasma 5). The measurement time width Tg, which is the time before the emission intensity decreases and starts to increase next, is used as the measurement time. That is, after the sample 3 is focused and irradiated with laser light, the delay time Td is provided and the measurement time width Tg is measured. Such measurement of plasma light in a specific time zone is referred to as time-resolved photometry. By using this time-resolved photometry, the spectral line intensity of the measurement target component can be measured more reliably.

  For example, when the delay time Td is set to 0 μsec, as shown in FIG. 5B, the spectral line intensity of lead (Pb) contained in the solder and the spectrum of other wavelengths around the lead (Pb) Since the line intensity approximates, it is difficult to determine whether the sample 3 contains lead (Pb). However, by providing a delay time Td (for example, 0.4 μsec), as shown in FIG. 5C, the spectral line intensity of lead (Pb) contained in the solder and the periphery of the lead (Pb) The difference from the spectral line intensities at other wavelengths becomes clear, and it can be reliably determined that the sample 3 contains lead (Pb). Thus, by providing the delay time Td, the spectral line intensity of the component to be measured can be measured more reliably and can be measured with high accuracy.

  Next, the laser energy amount of the laser light output from the laser oscillator 2 will be described with reference to FIG. Here, description will be made assuming that the sample 3 uses solder. FIG. 6A is a graph showing an example of the relationship between the laser energy amount of the laser beam and the spectral line intensity when the laser beam is focused on the solder, and the amount of laser energy in the X-axis direction is shown in FIG. The spectral line intensity is indicated in the Y-axis direction.

  FIG. 6B is a graph showing an example of a measurement result obtained by collecting and irradiating a laser beam with a laser energy of 90 mJ onto the solder and measuring the spectral line intensity of lead (Pb) contained in the solder. FIG. 6 (c) shows the measurement result of measuring the spectral line intensity of lead (Pb) contained in the solder by condensing and irradiating the same solder as in FIG. 6 (b) with laser light having a laser energy of 30 mJ. It is a graph which shows an example. FIG. 6B and FIG. 6C show the wavelength in the X-axis direction and the spectral line intensity at each wavelength in the Y-axis direction. Note that the above-described time-resolved photometric method (delay time Td is provided and measurement time width Tg is measured) is used for the measurement of spectrum light.

  FIG. 6A shows the measurement of the spectral line intensity of lead (Pb) contained in the solder when the laser beam is focused and irradiated while increasing the laser energy from 10 mJ to 90 mJ by 10 mJ. It is a graph which shows an example of a measurement result.

  As shown in FIG. 6A, the intensity of the spectral line measured by the spectroscope 8 is increased by increasing the laser energy focused on the solder from 10 mJ to 20 mJ. Similarly, when the laser energy is increased by 10 mJ, the spectral line intensity increases accordingly. However, when the laser energy is 40 mJ or more, the measured spectral line intensity decreases as the laser energy increases. That is, it is possible to measure a stronger spectral line intensity by controlling the laser energy amount to an appropriate value rather than simply increasing the laser energy amount for condensing and irradiating the solder.

  For example, as shown in FIG. 6B, when the solder is irradiated with a laser beam having a laser energy of 90 mJ, the spectral line intensity of lead (Pb) contained in the solder and other areas around the lead (Pb) Therefore, it is difficult to determine whether the sample 3 contains lead (Pb). However, when a laser beam with a laser energy of 30 mJ is focused and irradiated, as shown in FIG. 6C, the spectral line intensity of lead (Pb) contained in the solder and other wavelengths around the lead (Pb) The difference from the spectral line intensity becomes clear, and it can be reliably determined that the sample 3 contains lead (Pb). In the present embodiment, the amount of laser energy of the laser beam focused on the sample 3 is controlled to 30 mJ, so that the spectral line intensity of the measurement target component can be measured more reliably and measured with high accuracy. be able to. In addition, by setting the amount of laser energy focused and irradiated on the sample 3 to an appropriate value, the power consumption consumed by the laser oscillator 2 can be reduced, and the laser oscillator 2 can be downsized.

  Next, a component measurement process executed in the computer 10 configured as described above will be described with reference to the flowchart of FIG. FIG. 7 is a flowchart showing a component measurement process executed by the computer 10. This component measurement process is a process that is executed when a component measurement start instruction is input from the input device 15, and is a process that automatically measures the content rate of each measurement target component contained in the sample 3.

  In the component measurement process, first, the variable i is initialized to “1” (S1). Next, the i-th measurement is performed, and the content rate for each measurement target component obtained as a result of the measurement is stored in each content rate measurement result 14d1 to 14d5 of the measurement result memory 14d (see FIG. 2). A second measurement result acquisition process is executed (S2).

  Here, the i-th measurement result acquisition process (S2) will be described with reference to FIG. FIG. 8 is a flowchart showing the i-th measurement result acquisition process (S2). In the i-th measurement result acquisition process (S2), the gate controller 9 synchronizes the laser light irradiation of the laser oscillator 2 with the measurement of the plasma light by the spectroscope 8, and the plasma light measured by the spectroscope 8 is measured. It is a process for acquiring the content rate of each measuring object component from each spectrum.

  In the i-th measurement result acquisition process (S2), first, a variable j is initialized to “0” (S21). Next, a trigger signal is input to the gate controller 9, and the sample 3 is focused and irradiated with laser light (S22). Then, it is determined whether the variable j is “5” or more (S23). If the variable j is “5” or more (S23: Yes), the spectrum input from the spectroscope 8 is written in the RAM 13 (S24). . On the other hand, when the variable j is less than “5” (S23: No), the property in the vicinity of the surface of the sample 3 may be changed due to oxidation or the like. Is skipped and the process proceeds to S25.

  After a predetermined number of times (for example, five times) of focused laser beam irradiation, the sample 3 whose properties have changed is consumed (cut) by the predetermined number of times. The spectrum in which the influence of the changed sample 3 is suppressed can be measured, and the spectrum of the sample 3 can be measured with higher accuracy.

  Next, “1” is added to the variable j (S25), and it is determined whether or not the variable j is equal to “M” (M is an integer of 5 or more) (S26). When the variable j is smaller than “M” (S26: No), the process returns to the process of S22, and the processes of S22 to S26 described above are repeated. When the converging irradiation of “M” times of laser light is thus completed and the measurement results of “M-5” times are stored in the RAM 13, the variable j becomes equal to “M” (S26: Yes). ), The process proceeds to S27.

  In the process of S27, an average spectrum is created from the “M-5” spectra stored in the RAM 13 (S27). Since an average spectrum is created from “M-5” spectra and the content rate is acquired, spectrum measurement errors, noise, and the like are removed, and measurement accuracy can be improved.

  And the content rate of each measuring object component is each acquired from the calibration data 14a1-14a5 of each measuring object component memorize | stored in an average spectrum and the calibration data memory 14a (S28).

  Here, with reference to FIG. 3, an example of processing for acquiring (quantifying) the content of the measurement target component from the average spectrum will be described using lead (Pb) as an example.

  FIG. 3A is a graph showing an example of the content of an average spectrum created by the computer 10 when solder is measured, and FIG. 3B is a graph of lead calibration data 14a1 (FIG. 3) in the calibration data memory 14a. 2), calibration data indicating the relationship between the spectral line intensity and the content of lead (Pb) obtained experimentally in advance. The relationship between the spectral line intensity and the content rate is obtained experimentally in advance. Since the characteristic wavelength of lead (Pb) is 405.78 (nm), based on this, the spectral line intensity (3326 [au] of the characteristic wavelength of lead (Pb) in the average spectrum of FIG. .]).

  As shown in the calibration data shown in FIG. 3 (b), since the spectral line intensity and the content rate are in a substantially proportional relationship, using this correlation, the content of lead (Pb) is determined from the spectral line intensity. Rate can be obtained. That is, the spectral line intensity is 3326 [a. u. ], It can be acquired from FIG. 3B that the content is 103 [ppm]. Here, lead (Pb) has been described as an example, but for each measurement target component, the characteristic wavelength of each measurement target component and the spectral line intensity obtained experimentally in advance for each measurement target component are also described. The content rate in the sample 3 can be acquired based on the correlation between the content rate and the content rate.

  Now, the description returns to the flowchart of FIG. And each content rate of each measuring object component is written in each content rate measurement result 14d1-14d5 of the measurement result memory 14d as an i-th measurement result (S29), and this i-th measurement result acquisition process (S2) is completed. To do.

  The gate controller 9 can be controlled by the i-th measurement result acquisition process (S2) in the flowchart of FIG. 8 to synchronize the laser light irradiation of the laser oscillator 2 and the plasma light measurement by the spectroscope 8. . Moreover, the content rate of each measurement object component can be acquired from the spectrum of the plasma light measured by the spectrometer 8.

  After the completion of the i-th measurement result acquisition process (S2), the process returns to the process of S3 in FIG. In the process of S3, “1” is added to the variable i (S3), it is determined whether or not the variable i is larger than “N” (N is an integer of 2 or more) (S4), and the variable i is N or less. If there is (S4: No), the process returns to S2, and each process of S2 to S4 is repeated. Thus, when the measurement of N times is completed and the measurement result of N times is stored in the measurement result memory 14d, the variable i becomes larger than N (S4: Yes), and the process proceeds to S5.

  Next, the accuracy of the content rate of each measurement target component, which is a measurement result for N times, is evaluated. Note that the required accuracy and the allowable (evaluated as normal) content are different for each measurement target component. Therefore, calculation and evaluation of the accuracy determination value are all performed for each measurement target component.

  First, a standard deviation of one measurement target component among a plurality of measurement target components is calculated, and the standard deviation is divided by an average value used for calculating the standard deviation to obtain an accuracy judgment value (S5). . In the present embodiment, since N measurements are performed, N values (content ratios) measured for one measurement target component are stored in the respective content ratio measurement results 14d1 to 14d5 of the measurement result memory 14d. ing. These are read out, the standard deviation of the N content rates is calculated, and the standard deviation is divided by the average value of the content rates used to calculate the standard deviation to obtain an accuracy judgment value.

  Next, it is determined whether or not the obtained accuracy determination value is larger than the accuracy threshold (see FIG. 4A) stored in the threshold memory 14b (S6). If the accuracy determination value is larger than the accuracy threshold ( S6: Yes), it can be determined that the measurement accuracy is poor. Sample type (whether it is metal or resin), type of measurement target component to be detected (high and low detection sensitivity), influence of components other than measurement target component to be detected, laser oscillator 2 The accuracy of the measurement result may not be obtained depending on the accuracy of the spectroscope, the accuracy of the spectroscope 8, and the like. Therefore, in such a case, the measurement result for the content of the measurement target component is set to “unknown” (S8), and the process proceeds to S9. Thus, when the accuracy of the measurement result cannot be obtained, the reliability of the determination result can be increased by setting the measurement result to “unknown”.

  On the other hand, when the accuracy determination value is equal to or less than the accuracy threshold value (S6: No), that is, when the variation of the N content rates is small, it can be determined that the accuracy of the N measurement results is good. Therefore, let the average value of the N content rate be a measurement result (S7).

  Next, it is determined whether all the measurement target components have been evaluated (S9). If all the measurement target components have not yet been evaluated (S9: No), the process returns to S5, and the next measurement target component is evaluated. When the evaluation for all the measurement target components is completed while the processing is repeated in this way (S9: Yes), the measurement results for all the measurement target components are respectively displayed on the display device 16 (see FIG. 2). (S10), the process ends. By the component measurement process of the flowchart of FIG. 7, it is possible to measure the content of each measurement target component in which the influence of the sample 3 whose property has changed is suppressed, and the user can visually recognize the display device 16. In addition, it is possible to know the measurement result (content rate when normal or unknown) about the content rate of each measurement target component contained in the sample 3.

  According to this measuring apparatus 1, compared with the conventional fluorescent X-ray analysis method, a sample can be measured promptly at low cost without requiring an administrator or a management area. Further, the laser beam can be irradiated to a minute portion and can be irradiated even when the thickness of the sample 3 is thin, and its spectrum can be measured. For example, plating, solder joints on a substrate, etc. Even a thin specific area can be measured with high accuracy.

  Further, in the case of performing measurement using a conventional fluorescent X-ray analysis method instead of the measurement device 1, the sample 3 is irradiated with the X-ray, and the component of the sample 3 through which the X-ray is transmitted is measured. That is, since the component of the sample 3 at the site through which X-rays are transmitted is measured, it is unclear from what results are measured in a wide range in the X-ray irradiation direction what component is contained in which depth. is there. However, in this measuring device 1 (or measuring device 31 described later), the component to be measured is limited to the portion that is consumed by condensing the laser beam and becoming plasma, so that the local component is measured. It can be carried out.

  In addition, in the conventional emission analyzer using the laser microprobe emission spectroscopy, the periphery of the sample 3 is filled with an inert gas such as argon gas or vacuum in order to increase the light receiving sensitivity of the spectral line intensity. It was necessary to be in a state. However, if the measuring device 1 (or measuring device 31 described later) is used, the sample 3 can be measured in the atmosphere.

  Here, with reference to Fig.9 (a), an example of the relationship between the spectral line intensity | strength of lead (Pb) and content rate at the time of measuring a solder in air | atmosphere and argon gas using the measuring apparatus 1 is shown. Will be described. In this measurement, a plurality of solders having different lead (Pb) contents are prepared as Sample 3, and the lead (Pb) contents of each solder are measured.

  FIG. 9A is a graph showing an example of the relationship between the spectral line intensity of lead (Pb) and the content when solder is measured in the atmosphere and argon gas, and the content is in the X-axis direction. The spectral line intensity is indicated in the Y-axis direction.

  As shown in FIG. 9 (a), the spectral intensity of calibration data measured in the atmosphere tends to be slightly larger than the spectral intensity of calibration data measured in argon gas. The spectral line intensity and the content rate are substantially proportional to each other. That is, it is shown that the sample 3 can be measured in the atmosphere by using the space-resolved photometric method and the time-resolved photometric method described above and further controlling the amount of laser energy applied to the sample 3. That is, since a gas cylinder, a vacuum pump, and the like that have been necessary for the measurement are no longer necessary, the cost and size of the device can be reduced, and the user can use the device easily.

  Next, a thickness measurement process executed in the computer 10 will be described with reference to the flowchart of FIG. FIG. 10 is a flowchart showing the thickness measurement process executed by the computer 10. This thickness measurement process is executed when an instruction to start thickness measurement is input from the input device 15 and is a process for automatically measuring the thickness of each measurement target component included in the sample 3. .

When the sample 3 receives the focused laser beam irradiation, a part of the sample 3 is excited to generate plasma 5, and a crater-like hole is formed in the sample 3 irradiated with the laser beam focused irradiation. Is done. A depth of consumption of a single crater-like hole formed by condensing laser light irradiation is a value determined in advance experimentally, anti Worn amount memory 14c (see FIG. 4 (b)) Is remembered.

  In this thickness measurement process, when the content of each measurement target component of the sample 3 to be measured is substantially the same, the laser beam is repeatedly focused and irradiated, and the number of times the sample 3 is irradiated with the focused laser beam. The depth of the crater-like hole formed from is calculated. That is, this is a process for measuring the thickness of the layer which is the substantially same component in the sample 3.

  As shown in FIG. 10, in the thickness measurement process, first, the variable i is initialized to “1” (S31). Next, a trigger signal is input to the gate controller 9, and the sample 3 is focused and irradiated with laser light (S32). The content of each measurement target component is acquired from the spectrum input from the spectroscope 8 and the calibration data 14a1 to 14a5 of each measurement target component stored in the calibration data memory 14a (S33).

  And each content rate of each acquired measurement object component is written in each content rate measurement result 14d1-14d5 of the measurement result memory 14d as an i-th measurement result (S34). Next, a trigger signal is input to the gate controller 9 to focus and irradiate the sample 3 with laser light (S35), and the spectrum input from the spectroscope 8 and each measurement target component stored in the calibration data memory 14a. From the calibration data 14a1 to 14a5, the content ratio of each measurement target component is acquired (S36).

  It is determined whether the content rate of each measurement target component acquired in the process of S36 differs from the previous content rate acquired by a predetermined value or more (S37), and each of the measurement target components acquired in the process of S36 is determined. If the content rate is the difference between the previously acquired content rate and less than a predetermined value (S37: No), it can be determined that the components of the sample 3 are substantially the same, so this measurement is continued. The predetermined value varies depending on the sample 3 to be measured and the content of the measurement target component, and therefore must be experimentally calculated in advance. And the content rate of each measurement object component acquired in the process of S36 is written in each content rate measurement result 14d1-14d5 of the measurement result memory 14d as the i-th measurement result (S38), and "1" is added to the variable i. (S39), the process returns to the process of S35, and the processes of S35 to S39 described above are repeated.

  On the other hand, in the process of S37, when the content rate of each measurement target component acquired in the process of S36 is different from the previously acquired content rate by a predetermined value or more (S37: Yes), the “consumption” stored in the consumption memory 14c. The thickness of the sample 3 consumed by the measurement is calculated by multiplying “amount (50 nm)” and “i (number of times of laser light irradiation)”, and is written in the thickness measurement result 14d6 of the measurement result memory 14d (S40). . Then, the calculated thickness (thickness of the consumed sample 3) is output to the display device 6 (S41), and the thickness measurement process is terminated.

  When the measurement target component is specified from the content rate of each measurement target component included in the sample 3 by the thickness measurement process of the flowchart of FIG. 10, and the content rate of the measurement target component is substantially the same, The depth of the crater-shaped hole formed can be calculated from the number of times of irradiation of the laser beam focused and irradiated on the sample 3 by repeating the focused irradiation. That is, in the sample 3, the thickness of the layer that is substantially the same component can be measured.

  Here, an example in which the depth (thickness) of the plating layer is measured by the thickness measurement process will be described with reference to FIG. In this example, since iron (Fe) is used as a base material and the surface thereof is subjected to electroless nickel plating as sample 3, the components to be measured are iron (Fe), lead (Pb), and nickel (Ni). explain. Then, when the plating layer is consumed by condensing irradiation of the laser beam and the base material iron (Fe) is exposed, the depth (thickness) of the plating layer is determined from the number of times of irradiation of the condensing laser beam until then. )

  FIG. 9B is a graph showing an example of the relationship between the number of times the sample 3 is repeatedly focused and irradiated with the laser light and the spectral line intensity of each measurement target component obtained by the focused irradiation of the laser light. In the X-axis direction, the number of times of laser light irradiation is shown, and in the Y-axis direction, the spectral line intensities of iron (Fe), lead (Pb), and nickel (Ni) are shown.

  When the sample 3 is focused and irradiated with laser light, the spectral line intensities of iron (Fe), lead (Pb), and nickel (Ni) are measured. As shown in FIG. 9 (b), the spectral line intensity of each measured component to be measured (the content rate may be obtained from the calibration data) is a small amount due to variations in the distribution of plating components and measurement errors. There is a change but it is almost the same. For example, the spectral line intensity of iron (Fe) is 100 [a. u. ] After 120 times, the intensity of the spectral line of iron (Fe) starts to increase gradually, and when it exceeds 130 times, it rapidly increases. At 140 times, the spectral line intensity is about 2300 [a. u. In 150 times, about 5200 [a. u. ]. That is, it can be seen that between 130 and 150 times, the plating was consumed and iron (Fe) as a base material was exposed.

  For example, the predetermined value (change amount determination value) in the process of S37 of FIG. u. ], The change amount of the spectral line intensity is about 2000 [a. u. Therefore, the depth of a crater-like hole formed by 130 times of laser beam condensing irradiation is calculated. The distance in the depth direction of the sample 3 that is consumed by one time of condensing irradiation of the laser light is experimentally obtained in advance, for example, 50 nm, so that the depth is 50 nm × 130 times = 6.5 μm. It can be calculated as follows.

  According to the measuring apparatus 1 which is 1st Embodiment mentioned above until now, the content rate of each measuring object component by which the influence of the sample 3 in which the property changed was suppressed can be measured, respectively, It is possible to measure the thickness of layers that are substantially identical components. And since a measurement result is output to the display apparatus 16, a user visually recognizes the display apparatus 16, and the measurement result about the content rate of each measuring object component contained in the sample 3 (it contains when normal) Or the thickness of the layer which is substantially the same component in the sample 3 can be known.

  Next, the measuring apparatus 31 which is 2nd Embodiment is demonstrated. In the measuring device 31, laser light can be condensed and irradiated at an arbitrary position on a certain plane in the sample 3. The measuring device 31 performs focused irradiation of laser light on a plurality of positions of the sample 3 to measure the intensity of each spectral line, and displays the distribution of the content of each measurement target component of the sample 3 on the display device 16. Is.

  FIG. 11 is a block diagram illustrating a schematic configuration of the measurement apparatus 31. In the block diagram of FIG. 11, the same parts as those in the block diagram (see FIG. 1) of the measuring apparatus 1 according to the first embodiment are denoted by the same reference numerals and the description thereof is omitted, and only different parts are described. To do. The measuring device 31 includes the same part as the block diagram of the measuring device 1 shown in FIG. 1, an XY stage 21, and a computer 35.

  The XY stage 21 includes a table on which the sample 3 is placed, an X-axis transport motor (not shown) for transporting the table in the X-axis direction, and a Y-axis for transporting the table in the Y-axis direction. It has a direction conveying motor (not shown). The XY stage 21 is connected to the personal computer 10 via the I / F 22 (see FIG. 12), and the table is moved in the X-axis direction and the Y-axis direction according to a position control command input from the personal computer 35 described later. It is configured to be movable to an arbitrary position. That is, since the sample 3 also moves with the movement of the table, the laser beam can be focused and irradiated to an arbitrary position on a certain plane in the sample 3.

  Next, the computer 35 and various devices connected to the computer 35 will be described with reference to FIG. FIG. 12 is a block diagram illustrating a schematic configuration of the computer 35. In the block diagram of FIG. 12, the same parts as those in the block diagram (see FIG. 2) of the computer 10 of the measuring apparatus 1 according to the first embodiment are denoted by the same reference numerals, the description thereof is omitted, and different parts. Only will be described. The computer 35 has the same part as the block diagram of the computer 10 shown in FIG. 2 and an I / F 22.

  The I / F 22 is connected to the bus line 19. The I / F 22 connects the computer 35 and the XY stage 21. When a position control command is input from the computer 10 to the XY stage 21, the XY stage 21 moves the table to a predetermined position according to the command. Let

  Next, an XY position component measurement process executed by the computer 35 configured as described above will be described with reference to the flowchart of FIG. FIG. 13 is a flowchart showing the XY position component measurement process executed by the computer 35. This XY position component measurement process is a process executed when an instruction to start component measurement is input from the input device 15, and the distribution of the content rate of each measurement target component contained in the sample 3 placed on the XY stage. Is a process of measuring automatically.

  In the XY position component measurement process, first, the variable Y is initialized to “0” (S51), and the variable X is initialized to “0” (S52). Next, a position control command is input to the XY stage 21 via the I / F 22, and the XY stage 21 is moved to the position (X, Y) (S53).

  Then, the variable i is initialized to “1” (S54), the i-th measurement is performed, and the content rate for each measurement target component obtained as a result of the measurement is stored in the measurement result memory 14d (see FIG. 12). The i-th measurement result acquisition process stored in each of the content rate measurement results 14d1 to 14d5 is executed (the process of S2 in FIG. 8). When this i-th measurement result acquisition process (S2) is executed, each content rate of each measurement target component measured as the i-th measurement result is the content rate measurement result 14d1 to 14d5 in the measurement result memory 14d. Written to each.

  Next, “1” is added to the variable i (S55), and it is determined whether or not the variable i is larger than “N” (N is an integer of 2 or more) (S56). (S56: No), it returns to the process of S2, and repeats each process of S2-S56. When the measurement for N times is completed in this way and the measurement result for N times is stored in the measurement result memory 14d, the variable i becomes larger than N (S56: Yes), and the process proceeds to S57.

  Next, the accuracy of the content rate, which is a measurement result for N times, is evaluated. Note that the required accuracy and the allowable (evaluated as normal) content are different for each measurement target component. Therefore, calculation and evaluation of the accuracy determination value are all performed for each measurement target component.

  First, a standard deviation of one measurement target component among a plurality of measurement target components is calculated, and the standard deviation is divided by an average value used for calculation of the standard deviation to obtain an accuracy determination value (S57). . In the present embodiment, since N measurements are performed, N values (content ratios) measured for one measurement target component are stored in the respective content ratio measurement results 14d1 to 14d5 of the measurement result memory 14d. ing. These are read out, the standard deviation of the N content rates is calculated, and the standard deviation is divided by the average value of the content rates used to calculate the standard deviation to obtain an accuracy judgment value.

  Next, it is determined whether or not the obtained accuracy determination value is larger than the accuracy threshold (see FIG. 4A) stored in the threshold memory 14b (S58). If the accuracy determination value is larger than the accuracy threshold ( S58: Yes), it can be determined that the measurement accuracy is poor. Sample type (whether it is metal or resin), type of measurement target component to be detected (high and low detection sensitivity), influence of components other than measurement target component to be detected, laser oscillator 2 The accuracy of the measurement result may not be obtained depending on the accuracy of the spectroscope, the accuracy of the spectroscope 8, and the like. Therefore, in such a case, the measurement result regarding the content rate of each measurement target component at the position (X, Y) is set to “unknown” (S60), and the process proceeds to S61. Thus, when the accuracy of the measurement result cannot be obtained, the reliability of the determination result can be increased by setting the measurement result to “unknown”.

  On the other hand, when the accuracy determination value is equal to or less than the accuracy threshold value (S58: No), that is, when the variation in the N content rates is small, it can be determined that the accuracy of the N measurement results is good. Therefore, the average value of the N contents is taken as the measurement result at the position (X, Y) (S59).

  Next, it is determined whether all the measurement target components have been evaluated (S61). If all the measurement target components have not been evaluated yet (S61: No), the process returns to S57, and the next measurement target component is evaluated. When the evaluation for all the measurement target components is completed while the processing is repeated in this way (S61: Yes), “1” is added to the variable X (S62), and the variable X is “Xmax” (Xmax is It is determined whether or not it is equal to an integer of 1 or more (S63). When the variable X is smaller than “Xmax” (S63: No), the process returns to the process of S53, and the processes of S53 to S63 described above are repeated. Thus, when “Xmax” measurements are performed in the X-axis direction on the sample 3, the variable X becomes equal to “Xmax” (S63: Yes), and the process proceeds to S64.

  In the process of S64, “1” is added to the variable Y (S64), and it is determined whether or not the variable Y is equal to “Ymax” (Ymax is an integer of 1 or more) (S65). When the variable Y is smaller than “Ymax” (S65: No), the process returns to the process of S52, and the processes of S52 to S65 described above are repeated. Thus, when “Ymax” measurements are performed in the Y-axis direction on the sample 3, the variable Y becomes equal to “Ymax” (S65: Yes), and the process proceeds to S66.

  With the above-described processing, the measurement at each position from the position (0, 0) to the position (Xmax, Ymax) of the XY table 21 is completed on one plane of the sample 3 placed on the XY table 21. The measurement result is stored in each measurement target component 14d1 to 14d5 of the measurement result memory 13d. Then, a distribution map of each content rate in the XY plane is created for each measurement target component, and each result is displayed and output on the display device 16 (see FIG. 2) (S66), and the process is terminated.

  Through the XY position component measurement process of the flowchart of FIG. 13, the distribution of the content ratio of each measurement target component on a certain plane in the sample 3 can be measured, and the user visually recognizes the distribution map on the display device 16. Thus, the distribution of each measurement target component included in a certain plane in the sample 3 can be known.

  Next, with reference to Fig.14 (a), the distribution map of the content rate of each measurement object component produced by XY position component measurement process is demonstrated. FIG. 14A shows an example of a distribution diagram of the content ratio of lead (Pb) in the sample 3. Since the distribution charts of other measurement target components are the same, only the lead (Pb) distribution chart will be described here, and description of the other measurement target components will be omitted.

  The sample 3 placed on the XY table 21 is based on the position (0, 0) of the XY table 21, and “Xmax” measurements in the X-axis direction and “Ymax” measurements in the Y-axis direction. Is done. And the content rate of the lead (Pb) which is the measurement result is displayed on the display apparatus 16 as a distribution map, as shown to Fig.14 (a).

  In this distribution diagram, when the content of lead (Pb) is within a predetermined range in the measurement at the position (X, Y), the display of the position (X, Y) is blank, and the predetermined range. When it is outside, the color is changed and displayed. The value in the predetermined range is a value determined by the user according to the sample 3 to be measured, the content of the measurement target component, and the like. Thus, by creating and displaying the distribution map, the user can know the distribution of the content rate of each measurement target component included in the sample 3 by visually recognizing the display device 16.

  In the XY position component measurement processing described above, the content ratio of each measurement target component on a certain plane in the sample 3 was measured, but a specific position or a certain range was repeatedly measured to determine the depth direction. A distribution map may be created.

  Next, with reference to FIG. 14B, an example of measurement of the content rate of each measurement target component in the depth direction will be described. FIG. 14B shows an example of a distribution diagram of the content ratio of lead (Pb) in the depth direction in the A-A ′ cross section of FIG.

  As shown in FIG. 14 (a), even if the distribution of the content of lead (Pb) on a plane in the sample 3 is measured, only the surface of the sample 3 is measured. It is not possible to know how Pb) is distributed in the depth direction. However, the content of lead (Pb) in the depth direction can be measured by repeatedly measuring a specific position or within a certain range. FIG. 14B shows a distribution map obtained by repeatedly measuring the sample 3 located on the A-A ′ section line of FIG.

  In the distribution diagram of FIG. 14B, in the measurement of a certain depth at the position (X, Y (constant)), when the content ratio of lead (Pb) is within a predetermined range, the position (X, Y (Fixed)) is displayed with a solid color, and when it is out of the predetermined range, the color is changed. The value in the predetermined range is a value determined by the user according to the sample 3 to be measured, the content of the measurement target component, and the like.

  Thus, by creating and displaying the distribution map in the depth direction, the display device 16 can be visually recognized, and the distribution of the content rate of each measurement target component in the depth direction included in the sample 3 (that is, Can be known.

  The present invention has been described above based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various improvements and modifications can be easily made without departing from the spirit of the present invention. Can be inferred.

  For example, in the measurement apparatus 31 of the above-described embodiment, plasma light emitted in an oblique direction or a vertical direction with respect to the optical path L of the laser light that passes through the objective lens 4 and enters the sample is collected by the condenser lens 6. Although the light is input to the spectroscope 8, the plasma light emitted in the direction coaxial with the optical path L of the laser light may be measured.

  FIG. 15 is a diagram illustrating a schematic configuration of a first modified example of the measurement apparatus 1 and the measurement apparatus 31. As illustrated in FIG. As shown in FIG. 15, the laser light emitted from the laser oscillator 2 is reflected by the reflector 23 and is incident on the objective lens 4. The laser light incident on the objective lens 4 is condensed and irradiated onto the sample 3. Then, the plasma light emitted from the plasma 5 generated by the sample 3 is incident on the objective lens 4, condensed by the condenser lens 24, and measured by the spectroscope 8. The reflector 23 is a reflector having a small shape that does not affect the measurement of plasma light by the spectrometer 8. Thus, by measuring the plasma light radiated in the direction coaxial with the optical path L of the laser light, the objective lens 4, the condensing lens 24, and the reflector 23 can be arranged coaxially, so that the apparatus is downsized. be able to.

  Further, in the measurement apparatus 31, the XY stage 21 is moved to collect and irradiate a plurality of locations of the sample 3 with laser light, and the content of each measurement target component is measured. The laser oscillator 2 may be moved to focus and irradiate a plurality of locations on the sample 3 with laser light.

  The measuring device 31 measures a certain plane of the sample 3. However, an XYZ stage is provided, and the objective lens 4 and the laser oscillator 2 are moved in the X axis direction, the Y axis direction, and the Z axis direction, respectively. It is possible to make a three-dimensional measurement.

  Moreover, in the measuring apparatus 31, the measurement of the one plane in the sample 3 is performed in a plurality of places, and the distribution of the content ratio of each measurement target component is displayed. May be calculated and displayed on the display device 16 as a measurement result. By visually recognizing the display device 16, the user can know the average value of the content rates of the components to be measured at a plurality of locations on a plane in the sample 3.

  Further, in the measuring apparatus 1 and the measuring apparatus 31, the focusing lens 6 is focused on a part off the primary plume 5a, but the focusing lens 6 is focused on the primary plume 5a (or laser light irradiation). It may be configured to be fixed at a position). In this case, preferably, the incident end of the optical fiber is first installed at the focal point where the plasma light emitted from the plasma 5 is collected by the condenser lens 6, and the output end of the optical fiber is connected to the spectrometer 8. Then, the position of the incident end of the optical fiber is variably configured, and the incident end is shifted from the focal position, thereby changing the image of the plasma light incident on the incident end of the optical fiber. In other words, since the plasma light at the portion deviating from the focal point matched with the primary plume 5a is incident on the incident end of the optical fiber, the spectroscope 8 can measure the plasma light at the portion deviating from the primary plume 5a. .

  FIG. 16 is a diagram illustrating a schematic configuration of a second modification example of the measurement apparatus 1 and the measurement apparatus 31. As shown in FIG. 16, the focal point of the condensing lens 6 is fixed to a certain part from which the primary plume 5a is removed, and the condensing lens 6 and the spectroscope 8 are moved concentrically on the basis of the part. You may make it receive the plasma light irradiated from the plasma 5 at arbitrary angles (for example, the range of 0 degree to 90 degree | times) with respect to the optical path L of light.

  Further, in the measuring device 1 and the measuring device 31, measurement of the same part of the sample 3 is performed a plurality of times, the content rate of each measurement target component is obtained, the average value thereof is calculated, and the measurement result is displayed on the display device 16. May be. The user can know the average value of each measurement target component in the depth direction at the same location by visually recognizing the display device 16.

  In the measuring apparatus 1 and the measuring apparatus 31, the accuracy threshold value stored in the threshold value memory 14b is 5%. However, depending on the content rate of each measurement target component of the sample 3, the measurement environment, etc. It may be arbitrarily changed.

  Moreover, although the measuring apparatus 1 and the measuring apparatus 31 demonstrated as what test | inspects an electrical product or the components of a motor vehicle as the sample 3, the kind of sample 3 is not restricted to this, For example, the components of other apparatuses, Soil, water quality, raw materials and materials may be inspected.

  Moreover, although the measuring apparatus 1 and the measuring apparatus 31 were demonstrated as what measures the content rate of lead, mercury, cadmium, chromium, and bromine as a measuring object component, it measures about other measuring object components, Also good.

It is a block diagram which shows schematic structure of the measuring apparatus which is 1st Embodiment of this invention. 1 is a block diagram illustrating a schematic configuration of a computer according to a first embodiment of the present invention. (A) is a graph which shows an example of the content of the average spectrum created by the computer 10 when measuring solder, (b) is the spectral line intensity of lead (Pb) obtained experimentally in advance. It is a graph which shows an example of the content of the calibration data which shows the relationship between content rate. (A) is the schematic which shows an example of the content of the threshold value memory, (b) is the schematic which shows an example of the content of the consumption memory. (A) is a graph showing an example of the relationship between the emission intensity of plasma light emitted from solder and time, (b) shows no delay time Td, (c) shows delay time Td. Is a graph showing an example of a measurement result obtained by measuring the spectral line intensity of lead (Pb) contained in solder. (A) is a graph which shows an example of the relationship between the amount of laser energy of a laser beam, and a spectral line intensity at the time of condensing and irradiating a laser beam to solder, (b) is a laser energy of 90 mJ, c) is a graph showing an example of a measurement result of measuring the spectral line intensity of lead (Pb) contained in the solder by condensing and irradiating the solder with laser light at a laser energy of 30 mJ. It is a flowchart which shows the component measurement process performed with a computer. It is a flowchart which shows an i-th measurement result acquisition process. (A) is a graph which shows an example of the relationship between the spectral line intensity of lead (Pb) and the content when solder is measured in the atmosphere and argon gas, and (b) is repeated on sample 3. It is a graph which shows an example of the relationship between the frequency | count of irradiation of the laser beam condensed and the spectrum line intensity | strength of each measuring object component obtained by the focused irradiation of the laser beam. It is a flowchart which shows the thickness measurement process performed with a computer. It is a block diagram which shows schematic structure of the measuring apparatus which is 2nd Embodiment of this invention. It is a block diagram which shows schematic structure of the computer in 2nd Embodiment of this invention. It is a flowchart which shows the XY position component measurement process performed with a computer. (A) is an example of the distribution chart of the content rate of lead (Pb) in the sample, and (b) is the content of lead (Pb) in the depth direction in the AA ′ cross section of FIG. It is an example of the distribution map of a rate. It is a block diagram which shows schematic structure of the 1st modification of a measuring apparatus. It is a block diagram which shows schematic structure of the 2nd modification of a measuring apparatus.

1, 31 Measuring device 2 Laser oscillator (laser light output means)
3 Sample 4 Objective lens (optical system)
5 Plasma 5a Primary plume 6 Condensing lens (light receiving means)
8 Spectrometer (measuring means)
9 Timing control means 14c Consumption amount memory (first storage means)
14d Measurement result memory (second storage means)
21 XY stage (irradiation position moving means)
S10, S42, S66 Measurement result output means S28, S33, S36 Content rate measurement value acquisition means S31, S39 Counting means S37 Determination means S40, S41 Thickness calculation means

Claims (6)

A measurement device that measures the components of a sample by irradiating the sample with laser light and converting the components contained in the sample into plasma and analyzing the sample,
Laser light output means for outputting laser light;
An optical system for condensing and irradiating the sample with the laser beam output from the laser beam output means;
Of the plasma light emitted from the plasma generated when the sample receives the laser light, the sample is radiated obliquely or vertically with respect to the optical path of the laser light that passes through the optical system and enters the sample. measuring means for spectrally plasma light to measure the spectrum of the plasma light,
Timing control means for starting measurement of plasma light by the measurement means and controlling a measurement time zone of plasma light by the measurement means after a predetermined time has elapsed from the start of laser light output by the laser light output means;
Based on the spectrum measured by the measurement unit and the characteristic wavelength of the measurement target component, a content rate measurement value acquisition unit that acquires a content rate measurement value corresponding to the content rate of the measurement target component in the sample;
Counting means for counting the number of times the laser light is emitted from the laser light output means;
First storage means for storing a relationship between the number of times of irradiation of the laser light and a depth of a hole formed in the sample by the irradiation of the laser light;
Second storage means for storing the content rate measurement value acquired by the content rate measurement value acquisition means;
Whether the difference between the content rate measurement value stored in the second storage means and the content rate measurement value newly acquired by the content rate measurement value acquisition means is greater than or equal to a predetermined value, A determination means for determining before performing the laser light irradiation;
When the determination means determines that the difference is greater than or equal to a predetermined value, the number of irradiations counted by the counting means, the number of irradiation times of the laser light stored in the first storage means, and the laser light Based on the relationship with the depth of the hole formed in the sample by irradiation, thickness calculating means for calculating the thickness of the measurement target component in the sample,
A measurement apparatus comprising: a measurement result output unit that outputs the thickness of the measurement target component calculated by the thickness calculation unit as a measurement result. An irradiation position moving means for moving the irradiation position of the laser beam for condensing and irradiating the sample relative to the sample;
The measurement result output means outputs a measurement result based on the irradiation position of the laser light moved by the irradiation position moving means and the content rate measurement value obtained by irradiating the laser light at the irradiation position. The measuring apparatus according to claim 1 . 3. The measurement according to claim 2, wherein the measurement result output means outputs an average value of each content rate measurement value obtained by irradiating the laser beam to the plurality of irradiation positions in the sample as a measurement result. apparatus. The measurement result output means further irradiates the crater formed by the laser light irradiation in the sample with a laser light, and measures the average value of each of the plurality of content rate measurement values obtained by the multiple times of irradiation. measurement apparatus according to any one of claims 1 to 3, and outputs a. Comprising a counting means for counting the number of times of irradiation of the laser light output from the laser light output means,
The measurement result output means, according to claim 4, wherein a number of irradiations to be counted by said counting means outputs the result of measuring the average value of the content measurements obtained when at least a predetermined number of times Measuring device. A light receiving means for receiving the plasma light emitted from the plasma, focusing on a portion off the primary plume that is the central part of the plasma generated by the laser beam irradiation of the sample,
It said measuring means, disperses the plasma light received by said light receiving means, measuring device according to claim 1, wherein the measuring the spectrum of the plasma light 5.

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