JPH05256749A - Analysis pretreating instrument and pretreating method using instrument thereof - Google Patents

Abstract

PURPOSE:To make it possible to adjust the sample for total-reflection fluorescent X-ray analysis by providing an outer tube having the end part, which can hold the droplet of sample liquid to be analyzed, so as to surround the end part of a capillary, concentrating the sample liquid, and drying and fixing the liquid in a small area at the specified position of a drying plate for the sample liquid to be analyzed. CONSTITUTION:A tip part 3 of a capillary 2 is washed. Sample liquid of about 200mul is sucked into the capillary 2 through the tip part 3. Then, a wafer is set at a specified position and heated to 90-95 deg.C. Then, the tip part 3 of the capillary 2, which has sucked the sample liquid, is moved to the specified position on the wafer. The tip part 3 is lowered to a specified interval for the wafer, and the sample liquid is discharged slowly. A small droplet is formed between the tip part 3 and the wafer. The diameter of the droplet becomes constant by adjusting the discharging speed of the liquid and the evaporating speed by heating. For example, when the discharging speed is be made to about 10mul/minute at the surface temperature of about 90-95 deg.C, the diameter of the droplet becomes about 2mm. The droplet is dried and fixed in the intact state. Thus, the sample liquid of the large amount of liquid can be dried and fixed in the minute area at the set position of a dying plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pretreatment instrument for analyzing ultratrace amounts of impurities and a pretreatment method using the instrument.

[0002]

2. Description of the Related Art As a method for concentrating a substance to be analyzed in a liquid as a pretreatment for analysis, a method of evaporating and drying the liquid on an evaporation dish is generally used. In this case, since there is no suitable method to quantify the target substance widely dried on the concave surface (evaporation dish surface) with high sensitivity, usually, the dried substance is redissolved with a small amount of dissolution liquid, and analysis for liquid sample The analysis is performed by an instrument such as an ICP mass spectrometer or a liquid chromatograph.

Recently, a total reflection X-ray fluorescence analysis method has been developed for highly sensitive analysis of a local area of a flat plate-shaped surface. In this analysis method, when a liquid sample is to be analyzed, this droplet is dropped onto a high-purity quartz glass surface or a high-purity silicon single crystal wafer surface, which is evaporated to dryness,
Pre-treatment for concentrating locally on the plane is performed.

On the other hand, as a pretreatment method for concentrating metal impurities on the surface of a silicon wafer or the like and collecting it in a trace amount (that is, about 100 μl) of liquid, the wafer or the like is HF vaporized in a vapor phase decomposition apparatus. After the treatment, the acid droplets are held on the fluororesin holder by surface tension, the droplets are swirled from the center to the periphery of the wafer by a scanning device, and then the holder is moved to a saucer. There is known a method of recovering the liquid in which the metal impurities are collected.

[0005]

In the total reflection fluorescent X-ray analysis method, the dry solid portion of the droplet sample must be located in a portion where the X-ray irradiation dose is uniform and directly below the center of the window of the fluorescent X-ray detector. I have to. In an ordinary apparatus, the impurity dryness region on the flat substrate surface is within 5 to 6 mmφ at the most, and its position (address) must be recognized accurately.

Radioisotope ^{59 in} ultra high purity HF solution
When about 1 ppb of Fe is dissolved and 20 μl of the liquid is dropped on the hydrophobized silicon wafer substrate by spraying HF vapor in advance, droplets having a diameter of 4 to 5 mm are formed on the substrate. Dry it slowly to dryness, and use an autoradiograph
Examination of the dry state of ⁵⁹ Fe reveals that ⁵⁹ Fe is present up to a size almost the same as the diameter of the droplet before the start of dry solidification.

In the case of such trace impurities, since the evaporated liquid itself has high purity, no trace of dryness can be seen on the substrate. Moreover, the liquid droplets may move considerably in the initial stage of evaporation of the liquid droplets, and the dry solid portion is not always the same as the liquid dropping position. This is not preferable for measurement. If the dry-solid position cannot be accurately grasped, it is desirable that the droplet on the substrate is as small as possible. For example, if the diameter of the droplet is set to 3 mm, the amount of the dropped liquid is about 5 μl. Since the detection sensitivity of the analyzer does not change, reducing the amount of the dropped liquid will lower the analysis sensitivity of the liquid.

Therefore, a first object of the present invention is to dry an analytical sample liquid in an amount of several hundreds of microliters to a specified position on a dry substrate accurately and in a small area of 2-3 mmφ or less. An object is to provide an analytical pretreatment instrument and a pretreatment method. Further, in the field of semiconductors, it is important to transfer impurities on the surface of a silicon wafer to liquid droplets and analyze the liquid. In the present invention, a method of performing the transfer operation using the pretreatment tool and A second object is to provide a device necessary for the operation.

[0009]

According to the present invention, a thin tube having an end capable of holding a droplet of an analytical sample liquid, and an analytical sample provided so as to surround the end of the thin tube. An outer tube having an end capable of holding a liquid droplet, and a mechanism for sucking and discharging an analytical sample solution is connected to the other end of the thin tube. An analytical pretreatment instrument is provided in which a mechanism is connected to the tube to suck or depressurize the internal atmosphere.

The thin tube, outer tube, etc. are made of hydrophobic synthetic resin,
For example, polytetrafluoroethylene (PTFE), tetrafluoroethylene perfluoroalkoxyethylene (PF
A), preferably made of a fluororesin such as Teflon AF under the trade name, and a second outer tube may be provided further outside the outer tube.

According to the present invention, the analytical sample solution is sucked into the thin tube in advance by using the analytical pretreatment device, and the end of the thin tube is dried by the hydrophobic analytical sample solution heated to a constant temperature. The sample liquid is gradually ejected from the thin tube in close proximity to the plate, and the ejected sample droplet is in contact with the end of the thin tube and vaporized so that the droplet does not spread beyond a certain diameter. A method for pretreatment of analysis is provided, wherein the evaporation material is sucked and removed by an exhaust mechanism connected to an outer tube, and the analysis sample solution is concentrated and dried in a designated region on the drying plate.

The hydrophobic analysis sample liquid drying plate is a silicon wafer immersed in HF, a silicon wafer heated and ultrasonically treated with an aqueous solution of an organic strong alkali and a surfactant, a silicon wafer coated with a trade name of Teflon AF very thinly, etc. Is useful.

As the analytical pretreatment instrument, an instrument in which a second outer tube is provided further outside the outer tube so as to surround the outer tube can be used. The atmosphere can be supplied from the second outer tube.

According to the present invention, as an apparatus for carrying out the above analytical pretreatment method, the analytical pretreatment instrument, the arm for holding the analytical pretreatment instrument, the mechanism for moving the arm, the analytical sample A drying plate for drying the liquid, a driving mechanism for moving the position of the drying plate so that the end portion of the analytical pretreatment instrument held by the arm is set at a predetermined position of the drying plate, and There is provided an analytical pretreatment device comprising a heating mechanism provided on the opposite side of the drying plate corresponding to the end of the analytical pretreatment instrument held by the arm.

Further, according to the present invention, as a method for collecting impurities adhering to a hydrophobic analysis surface such as a silicon wafer, a thin tube having an end portion for sucking or discharging an analytical sample liquid, and the end of the thin tube. A liquid for dissolving and collecting impurities on the analytical surface in the narrow tube, using an analytical pretreatment instrument having an outer tube provided with an end portion for holding a droplet of the analytical sample liquid provided so as to surround the portion. Is aspirated, the pretreatment device is positioned so that the end of the outer tube is close to the hydrophobic analysis surface, and the liquid is discharged from the thin tube to deposit the droplet on the hydrophobic analysis surface in the outer tube. By forming a small amount of pressure inside the outer tube so that the droplet does not stick out from the outer tube, the pretreatment instrument is moved to scan the droplet on the hydrophobic analysis surface. The feature is that the impurities on the hydrophobic analysis surface are collected in the droplets. Analysis pretreatment method is provided that.

Also in the above-mentioned pretreatment method, as the analytical pretreatment instrument, an instrument in which the second outer tube is provided outside the outer tube so as to surround the outer tube can be used. Further, the movement of the pretreatment device for analysis for scanning the droplet can be performed by a robot mechanism.

According to the present invention, after the impurities are collected in the liquid droplets by the above method, the liquid droplets are sucked into a thin tube, moved to a liquid droplet drying area, and dried. An analytical pretreatment method is provided for performing.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail based on specific examples shown in the accompanying drawings.

Example 1 In FIG. 1 showing an analytical pretreatment instrument having a double-tube structure according to the present invention, this analytical pretreatment instrument is basically referred to as PTFE.
A cylindrical support 1 made of PFA, a thin tube 2 made of PFA extending through the center of the support 1, and an elongated hole 6 formed in the support 1 substantially parallel to the thin tube 2. A transparent fluororesin outer tube 5 (inner diameter: Teflon AF) provided at the lower end of the support 1 so as to surround the tip of the thin tube 2.
About 10 mm) and.

The tip portion 3 of the thin tube 2 has an inner diameter narrowed to about 0.1 mm, and the tip portion 4 of the outer tube 5 is located substantially flush with the tip portion 3. A projecting tube portion 7 for connecting an exhaust tube is formed at the upper end of the elongated hole 6. The outer tube 5 may be a PFA tube whose thickness is made sufficiently thin so that the tip 3 of the thin tube 2 can be seen.

A method of using the above-described analytical pretreatment device to concentrate the analytical sample solution and to form a dry solid portion having a diameter of 2 mm or less at a specific position on the analytical sample solution drying plate will be described.
In order to confirm by the RI tracer method how much the analysis target in the analysis sample solution migrates to the dry solid portion, a 0.01% Fe 0.01 ppb HF 10% solution labeled with ⁵⁹ Fe was prepared. As the analytical sample liquid drying plate, a silicon wafer whose surface was made hydrophobic by immersion in HF was used.

FIG. 2 shows a droplet drying apparatus used for drying the above-mentioned analytical sample liquid. That is, the drying wafer 8 is accurately positioned and held on the quartz glass plate 10 by the knob 11. The quartz glass plate 10 is movable in the horizontal direction by the XY stage 9 and is fixed in position at a designated position. Below the quartz glass plate 10 is a halogen lamp for heating.
Twelve are placed. This halogen lamp 12 is housed in a quartz container 13 whose inside can be ventilated and air cooled.

Above the quartz glass plate 10, the above-described analytical pretreatment instrument of the present invention is arranged. In the pretreatment instrument, an arm 14 is connected to the support 1, and its position can be freely adjusted by vertical movement, rotation, slide and the like. Furthermore, the thin tube 2 has a dispenser
An exhaust mechanism 16 such as a water flow pump using ultrapure water is connected to the protruding pipe portion 7.

First, by the operation of the arm 14, the tip portion 3 of the thin tube 2 of the pretreatment instrument is transferred to a predetermined washing tank, and if necessary, a chemical solution treatment is performed and water washing is performed. Next, only the tip portion 3 of the thin tube 2 enters the sample tank, and the dispenser 15 is operated in reverse so that 200 μl of the sample solution is accurately sucked into the thin tube 2. In addition, the stage 9 is operated to set the wafer 8 to a specified position, and the lamp 12 moves the wafer 8 to 90-
Heat to 95 ° C.

Further, the thin tube 2 sucking the sample solution is moved by moving the arm 14 so that the tip portion 3 thereof is located at the designated position on the wafer 8. Here, when the tip portion 3 of the thin tube 2 is lowered to the wafer 8 at a constant interval, the operation of the exhaust mechanism 16 starts,
The sample liquid is gradually discharged by operating the dispenser, and small droplets are formed between the tip portion 3 of the thin tube 2 and the wafer 8. In addition, the XY stage 9 is adjusted in advance so that the position of the small droplet becomes the designated position. The positional accuracy of the liquid droplet is determined by the accuracy of the XY stage 9, but normally,
It is about ± 0.1 mm, and the positional accuracy required for the analyzer can be sufficiently obtained. The drying plate is placed at a position where it is heated uniformly on the heating device, and the support 1, that is, the tip 3 of the thin tube 2 is moved to the X position.
The structure may be such that the Y stage 9 moves to a designated position on the drying plate.

The diameter of the droplet depends on the discharge speed of the liquid and the evaporation speed of the liquid due to heating. Therefore, by appropriately adjusting the discharge rate and the lamp voltage of the lamp 12, the discharge rate and the evaporation rate reach equilibrium, and the diameter of the liquid becomes substantially constant. For example, when the discharge rate was 10 μl / min at the surface temperature (90 to 95 ° C.), the diameter of the liquid droplet was about 2 mm, and the liquid dried as it was.

As in the conventional case, if 1 drop is used for dryness, 1
The dry solid area cannot be 2 mmφ unless the sample liquid has a volume of about 2 μl. On the other hand, according to the present invention, it is understood that the sample liquid having a much larger amount of liquid than the conventional one can be dried at a preset position on the drying plate with a small area.

In the above, the amount of radioactivity in the dried and solidified portion was 97% of the initial 200 μl sample liquid, and it is considered that 3% was scattered. This recovery rate is well tolerated when analyzing ordinary trace impurities. Therefore, if the contamination from the device or the environment can be prevented, the sensitivity of the analysis can be greatly increased, and the pretreatment method of the present invention using the pretreatment instrument is a very effective method.

For comparison, when the outer tube 5 was removed from the pretreatment apparatus and the same experiment was conducted and an autoradiograph of the entire surface of the wafer 8 was performed, ⁵⁹ Fe was scattered in a fairly wide range. And it turned out to be contaminated. Further, the same experiment was conducted again with the outer tube 5 attached, but ⁵⁹ Fe contamination was not found in the wafer portion outside the outer tube 5. By using the double pipe structure pretreatment tool of the present invention, it is possible to form dry-solid parts for analysis at a plurality of addresses on the drying plate, and it is possible to perform efficient analysis.

Example 2 FIG. 3 shows a pretreatment device having a triple structure according to the present invention. In this pretreatment instrument, like the pretreatment instrument of FIG. 1, the support 1 is provided with the thin tube 2, the long hole 6 and the outer tube 5, and the second tube is further provided so as to surround the outer tube 5. Outer tube of 17
Is provided. The space between the second outer pipe 17 and the first outer pipe 5 communicates with a long hole 16 penetrating a portion connecting both upper outer pipes. , A projection tube for connecting with an atmosphere supply tube (not shown)
19 are formed. Further, the lower end portion 18 of the second outer pipe 17 is
It is slightly shorter than the lower end of the first outer pipe 5, and the lower end 3 of the thin pipe 2 and the lower end of the outer pipe 5 are the second outer pipe 17
It is adapted to project outwardly from the lower end portion 18 of the.
The second outer tube 17 is also made of a hydrophobic synthetic resin and is formed integrally with the support 1, for example.

The pretreatment instrument having the triple tube structure shown in FIG. 3 was attached to the arm in the same manner as in FIG. 2, and the same experiment as in Example 1 was conducted. In this case, high-purity dustless nitrogen gas heated to approximately 80 ° C. was supplied through the long hole 16 at the same time as the exhaust from the long hole 6 while balancing the exhaust amount.

The droplets formed at the end 3 of the thin tube 2 were controlled to be even smaller, and the dry-solid region could be 1 to 1.5 mmφ. The recovery rate of ⁵⁹ Fe in the dry solid portion was 91%, and the amount of scattering was slightly large, but this method can be sufficiently applied when the demand for the analytical value is one digit. Since a general high-sensitivity analytical instrument has an accuracy of this level for the analysis of an extremely small amount, the concentration treatment method using such a pretreatment instrument with a triple tube structure is
It can be put to practical use.

Example 3 In the pretreatment instrument device having a double-tube structure shown in FIG. 1, since the outer tube 5 is hydrophobic, the outer tube 5 is moved on the hydrophobic surface while holding the aqueous droplets at the ends thereof. You can A method for forming an analysis sample droplet on the surface of a wafer while dissolving impurities attached thereto will be described in this embodiment.

In order to investigate how much impurities on the wafer surface can be collected in the droplet, the tracer technique using a radioisotope was used as in Example 1. Cu attached to the silicon surface in the coexistence of reducing substances from HF-based chemicals
The collection rate by HF droplets following the gas phase decomposition method has a very poor recovery rate. Moreover, the recovery is poor in reproducibility. Therefore, in this example, the droplet collection of ⁶⁴ Cu, which had been difficult to collect by adhering only to the mirror surface side of the silicon wafer in this way, was tried by the treatment method using the pretreatment device for analysis of the present invention.

As shown in FIG. 4, the wafer 20 is placed in a dish-shaped container 21.
1 is held horizontally, and the end 4 of the outer tube 5 of the pretreatment tool shown in FIG. 1 is in contact with the surface of the wafer 20, and the pretreatment tool is supported so that the processing tool can be freely scanned in this state. The body 1 is held by the arm 22 of a predetermined robot mechanism.

First, as in the first embodiment, the tip portion 3 of the thin tube 2 is cleaned by the operation of the arm 22, and then the tip portion 3 of the thin tube 2 is placed in the chemical solution tank of the wafer surface impurity solution.
Put the chisel and reverse the dispenser 15 to 100 ~
Inhale 200 μl of liquid. In addition, as the above-mentioned solution, in order to dissolve ⁶⁴ Cu, a solution in which 3% of HF was added to an aqueous solution of nitric acid: water of 1: 1 was used.

Further, the arm 22 is operated to move the pretreatment tool to a predetermined analysis region on the wafer 20 so that the state of FIG. 4 is obtained, and the dispenser 15 is rapidly operated to move the inside of the outer tube 5 to the above-mentioned state. Discharge the acid solution. In this case, due to the surface tension, the droplet does not overflow to the outside of the outer tube 5. At the same time, the exhaust mechanism 16 communicating with the inside of the outer tube 5 is cut by the valve 23, and the separately connected dispenser 15 ′ is slightly sucked to slightly depressurize the inside of the outer tube 5.

In this state, the robot mechanism scans the pretreatment instrument through the arm 22 to scan the droplets on the wafer 20. In this case, the wafer
The scanning of the droplets on 20 is performed in a so-called one-stroke writing. Further, for example, it is possible to start from parallel to the orientation flat and collect impurities in a half of the wafer by reciprocal scanning of a seven-curve system.

By moving the droplets at a constant speed, the entire surface scanning on the wafer was completed in 15 minutes. A comparison of the radioactivity measurements showed that 82% of the ⁶⁴ Cu on the wafer was trapped in the droplet. This is about twice the value compared to the case where only HF is scanned. Incidentally, in the present invention, even if the position of the support 1 is fixed and the dish container 21 is moved by the robot mechanism, it is relatively the same as the above-mentioned device.

Example 4 In order to further increase the recovery rate of ⁶⁴ Cu as compared with Example 3, it is necessary to increase the concentration of nitric acid to nearly 60% by weight. However, in the case of containing HF, when the liquid comes into contact with the reducing impurities, an oxidizing gas is generated, which deteriorates the surface of the silicon holding the droplets and makes them hydrophilic.
Since the altered surface captures the liquid, the amount of droplets that can be collected is reduced.

Therefore, using the triple tube structure pretreatment tool used in Example 2 shown in FIG. 3, the same wafer as in Example 3 was treated with an aqueous solution of 55% nitric acid and 2% hydrofluoric acid. A similar scan was performed using As a result, the scan was completed without the droplet remaining on the wafer, and by comparison of the radioactivity measurements, 93% of ⁶⁴ Cu on the wafer was collected in the droplet. From this, the usefulness of the triple tube structure pretreatment device is understood.

Example 5 After performing the same scanning using the wafer of Example 4, immediately the dispenser 15 was made to reversely act to suck all the droplets into the thin tube 2. This pretreatment device having a triple tube structure was replaced with the arm 14 on the XY stage of Example 1, and the droplets were dried and solidified at the designated position as in Example 1.
The droplets formed were about 2.5 mm in size, and it was confirmed from the measured values of radioactivity after drying that 90% of ⁶⁴ Cu on the wafer was dried. From this result, it is understood that the impurity on the wafer can be concentrated and the analytical sample can be dried to a small area at the specified position on the drying plate with sufficient accuracy by using only one pretreatment tool. It

[0043]

According to the analytical pretreatment instrument of the present invention, the analytical sample liquid can be concentrated and dried at a designated position on the analytical sample liquid drying plate to have a diameter of 2 to 3 mm. A sample for reflected X-ray fluorescence analysis can be prepared. Furthermore, by making this pretreatment instrument a triple tube structure, it becomes possible to dry and solidify in a smaller area, and the surface such as Auger spectroscopic analysis and X-ray photoelectron spectroscopic analysis which are already widely used but have poor detection sensitivity. Concentration is possible with which effective information can be obtained even with an analyzer. Further, according to the present invention, it is possible to collect and concentrate the impurities on the surface of the silicon wafer by using the same device as the pretreatment device described above. It has become possible to carry out instrumental analysis more effectively.

[Brief description of drawings]

FIG. 1 is a view showing an analytical pretreatment instrument of the present invention having a double tube structure.

FIG. 2 is a diagram simply showing an overall configuration of an analysis pretreatment apparatus using the analysis pretreatment instrument of FIG.

FIG. 3 is a view showing an analytical pretreatment instrument of the present invention having a triple tube structure.

FIG. 4 is a diagram illustrating a method of collecting trace impurities on a hydrophobic surface in a droplet using the analytical pretreatment instrument of FIG. 1.

Claims (10)

[Claims] 1. A thin tube having an end capable of holding a droplet of an analysis sample liquid, and a droplet of an analysis sample liquid provided so as to surround the end of the thin tube. An outer tube having an end portion is provided, and a mechanism for sucking and discharging an analytical sample solution is connected to the other end portion of the thin tube, and the outer tube is sucked or sucked into its internal atmosphere. An analytical pretreatment instrument characterized in that a mechanism for reducing the pressure is connected. 2. The analytical pretreatment instrument according to claim 1, wherein the thin tube and the outer tube are formed of a hydrophobic synthetic resin. 3. The analytical pretreatment instrument according to claim 1, further comprising a second outer tube provided outside the outer tube so as to surround the outer tube. 4. An analytical sample liquid is preliminarily sucked into the thin tube by using the analytical pretreatment instrument according to claim 1, and an end of the thin tube is placed on a hydrophobic analytical sample liquid drying plate heated to a constant temperature. The sample liquid is gradually discharged from the thin tube in close proximity to the sample, and the discharged sample droplet is vaporized so that it is in contact with the end of the thin tube and does not spread beyond a certain diameter. A pretreatment method for analysis, characterized in that the substance is sucked and removed by an exhaust mechanism connected to an outer tube, and the analysis sample liquid is concentrated to dryness in a designated region on the drying plate. 5. An instrument in which a second outer tube is provided further outside the outer tube so as to surround the outer tube is used as the analytical pretreatment instrument, and the second outer tube is used at the same time as the evaporative substance is exhausted. The pretreatment method for analysis according to claim 4, wherein an atmosphere is supplied from 6. The analytical pretreatment instrument according to claim 1, an arm for holding the analytical pretreatment instrument, a mechanism for moving the arm, a drying plate for drying an analytical sample solution, and an arm held by the arm. Corresponding to the drive mechanism for moving the position of the drying plate so that the end of the analytical pretreatment device is set at a predetermined position of the drying plate, and the end of the analytical pretreatment device held by the arm. The analytical pretreatment apparatus further comprises a heating mechanism provided on the opposite side of the drying plate. 7. An outer tube provided with a thin tube having an end for sucking or discharging an analytical sample solution, and an outer tube provided so as to surround the end of the thin tube and for holding a droplet of the analytical sample solution. Using an analytical pretreatment instrument having and preliminarily sucking a liquid for dissolving and collecting impurities on the analytical surface in the thin tube, so that the end of the outer tube is close to the hydrophobic analytical surface. Position the instrument, discharge the liquid from the thin tube to form the droplet on the hydrophobic analysis surface in the outer tube, and slightly reduce the pressure in the outer tube as necessary so that the droplet does not stick out from the outer tube. At the same time, the pretreatment device is moved to scan the droplet on the hydrophobic analysis surface to collect impurities on the hydrophobic analysis surface in the droplet. .. 8. An instrument in which a second outer tube is provided further outside the outer tube so as to surround the outer tube is used as the analytical pretreatment instrument, and exhaust is performed through the second outer tube. Item 8. The pretreatment method for analysis according to Item 7. 9. An analysis pretreatment in which after the collection of the impurities in the droplets according to claim 7 is completed, the droplets are sucked into a narrow tube and moved to a droplet drying area for dryness. Method. 10. A thin tube having an end for sucking or discharging an analytical sample solution, and an outer tube provided with an end for holding a droplet of the analytical sample solution provided so as to surround the end of the thin tube. And a robot mechanism in which an outer tube end of the analysis instrument always moves close to the surface of the wafer to be analyzed and the entire surface of a predetermined analysis region is scanned. Analytical pretreatment equipment.