JPH0627718B2 - Area analysis method - Google Patents

Description

Detailed Description of the Invention a. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an area analysis method, and more particularly to an area analysis method for two-dimensionally analyzing a distribution state of a compound on a sample surface of an element of interest in a sample.

B. 2. Description of the Related Art An X-ray microanalyzer is an apparatus for two-dimensionally scanning and analyzing a sample surface. This apparatus adjusts the X-ray spectroscope according to the characteristic X-ray wavelength of the element to be detected in the sample. Since the sample surface is scanned with an electron beam, elemental surface analysis is possible, but in the case of compound analysis, X
Since the line spectroscope scans the wavelength, the compound analysis by the X-ray microanalyzer could only be a point analysis, not an area analysis.

C. Object The present invention uses an X-ray microanalyzer to determine the chemical bond state (distribution state of a compound) of one target element in a sample.
An object is to provide a surface analysis method for performing a dimensional analysis.

D. Constitution The present invention relates to the characteristics X of an element depending on the difference in the bonding state between the elements.
Using the fact that the wavelength of the line shifts, the half-width of the characteristic X-ray peak changes, or the intensity ratio of the Lα and Lβ lines changes, the measurement points are arranged two-dimensionally on the sample surface. X-ray detection intensities of two or more wavelengths are measured at each measurement point, and the results are subjected to data processing to measure the distribution of the binding states of the constituent elements on the sample surface, that is, the distribution state of the compound.
The line spectroscope is characterized in that it does not perform wavelength scanning, and it scans the sample surface with one wavelength fixed, then changes the wavelength and scans the sample surface again. The X-ray spectroscope may be set to different wavelengths to collect necessary data in one scan of the sample surface, and either method may be used.

E. Embodiment FIG. 1 shows an embodiment of an apparatus for carrying out the present invention. Reference numeral 1 is a sample, 2 is an electron beam for exciting the sample, 3 is an X-ray emitted from the sample, 4 is a dispersive crystal, and 5 is an X-ray detector.
A control computer 6 drives the sample stage 8 and the X-ray spectroscope 9 via the output interface 7, and reads the output of the X-ray detector 5 via the input interface 10 to read the memories M1, M2, etc. To memorize.

FIG. 2 shows the operation of the control computer 6. The computer 6 displays the sample surface as n of P11 to Pnn as shown in FIG.
^The sample stage 8 is divided into two minute regions, the sample stage 8 is driven, and these minute regions are sequentially moved to the irradiation point of the electron beam 2, and the output of the X-ray detector 5 at that time is read. Second
In the figure, when the device is started, the initialization operation (a)
The indexes i and j for designating the stage position are set to 1, and then the X-ray spectroscope 9 is driven to the previously designated first wavelength λ1 position (b), and the stage 8 is driven to the position P11. (C) Then the measurement is started, the output data of the first X-ray detector is stored in the M1 channel of the memory (g), and when the sample stage reaches Pnn, step (d) is NO when the measurement operation is the first time. Then, the indices i and j are both set to 1 (e), and the X-ray spectrometer 9 is designated in advance.
Drive to the position of wavelength λ2 of (f) and the operation returns to point A,
The same operation as described above is repeated, the second measurement data is stored (h) in the M2 channel of the memory, and when the end of the second measurement is detected in step (d), the computer 6 stores it in the memories M1 and M2. The stored data is read out and an operation is performed to determine the compound in each region of P11 to Pnn on the sample, and the compound is displayed by the display device 11.

When examining the oxidation state of the surface of iron, the intensity ratio of the Lα line and the Lβ line of iron is different in the case of iron alone, the divalent oxidation state, and the trivalent oxidation state. Therefore, the X-ray spectroscope is set at the position of Lα of iron in the first measurement, and set at the position of Lβ in the second measurement. Calculation is P11 to Pnn
Calculate the ratio of the measured values of Lα and Lβ at each point of
When the oxidation state of divalent or trivalent is determined, the simple substance is represented by 0, the divalent is represented by the number 2 and the trivalent is represented by the number 3, and the printout is made in correspondence with P11 to Pnn. You can It is also possible to display in color with a color CRT.

In the above-mentioned embodiment, one X-ray spectroscope switches the wavelength position and repeats the measurement a plurality of times. However, a plurality of X-ray spectroscopes are arranged around the sample, which is necessary in one measurement operation. It is also possible to collect data. Further, the scanning of the sample surface may be performed by deflecting the electron beam instead of moving the sample stage.

F. Effect According to the present invention, since wavelength scanning is not performed by the X-ray spectrometer,
Even if the sample surface is scanned, compound analysis of the sample surface of one target element in the sample can be completed within a practical time, and even a real sample such as a corrosion test piece or a real sample peeled off from the surface of the current deviceゝ Can express the chemical change of the surface two-dimensionally.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of an apparatus for carrying out the present invention, FIG. 2 is a flow chart of operation, and FIG. 3 is a diagram showing an array of analysis points on a sample surface. 1 ... Sample, 2 ... Electron beam, 3 ... X-ray, 4 ... Spectroscopic crystal, 5 ... X-ray detector, 6 ... Control computer,
7 ... Output interface, 8 ... Sample stage, 9
... X-ray spectrometer, 10 ... Input interface, M
1, M2 ... Memory.

Claims (1)

[Claims] 1. A sample surface is irradiated with an electron beam, X-rays radiated from the sample are dispersed, two-dimensional measurement points are set on the sample surface, and each measurement point has a purpose on the X-ray spectrum. Two X-ray wavelength points corresponding to two points on one characteristic X-ray peak profile of one element or K of the same element
X-ray intensity is measured at wavelength points of two adjacent peaks appearing as a pair of X-ray, L-line, etc., and calculation is performed for each measurement point to obtain a ratio of the measured intensities of the X-rays of the two wavelengths, A surface analysis method characterized in that the bonding state of the target element in the sample is identified by the value of the ratio, and the result is two-dimensionally displayed.