JP2999072B2 - Surface analyzer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface analyzer provided in a surface reforming apparatus such as a vacuum evaporation apparatus and an ion implantation apparatus, and is applicable to a space telescope such as an artificial satellite and an observatory. is there.

[0002]

2. Description of the Related Art Electron probe microanalysis, particle beam excitation X
In X-ray radiation analysis, soft X-ray appearance voltage spectroscopy, X-ray fluorescence spectroscopy, etc., the characteristic X
It is common to wavelength analyze the lines. In order to perform a two-dimensional analysis, the irradiated points are sequentially moved (scanning) over the entire surface to be analyzed.

FIG. 6 shows a prior art. As shown in FIG. 6, the electron beam 2 emitted from the electron gun 20 toward the sample 4 is focused by a focusing coil 21 in a spot shape, and at the same time, the electron beam 2 is deflected by an electron beam scanning polarizing plate 22. Then, the sample irradiation surface 4 is scanned 23. Also,
The electron beam scanning deflection plate 22 includes a scanning scanning circuit 29.
It is driven by.

Here, the sample 4 irradiated with the electron beam 2
The characteristic X-rays generated from the irradiated surface are converted into information on the reflection angle by the spectral crystal 25 and detected by the X-ray detector 26. This characteristic X-ray has wavelength information specific to the element on the sample surface. Then, the output from the X-ray detector 26 is amplified by the preamplifier 30 and input to the image processing device 31. The timing signal from the scanning scanning circuit 29 is also input to the image processing device 31.

Accordingly, the image processing device 31 processes the amplified signal from the preamplifier 30 together with the timing signal from the scanning scanning circuit 29 to form an image showing the two-dimensional element distribution on the scanned sample surface. It can be output to the monitor 9 and displayed.

[0006]

In the prior art shown in FIG. 6, a spot-focused electron beam 2 is scanned 23, and characteristic X-rays are detected by an X-ray detector 26, so that a flat surface is obtained. Surface elemental analysis can be performed. However, since a certain period of time is required for scanning a certain plane area, a composition analysis image cannot be obtained immediately.

[0007] The analysis range when scanning is not performed is generally as narrow as 1 cm ² or less, and cannot be applied to a production line as it is. The present invention has been made in view of the above-described conventional technology, and has as its object to provide a surface analysis apparatus that can immediately perform a planar composition distribution analysis without performing scanning.

[0008]

In order to achieve the above object, the present invention uses the following means. (1) Targets for generating characteristic X-rays are a heating electron beam and an ion implantation ion beam. (2) An X-ray imaging system such as a pinhole and an X-ray mirror is used for X-ray imaging. (3) For X-ray detection, a charge-coupled device (CC) having not only energy resolution but also positional resolution
D: Charge Coupled Device) or the like is used. (4) A discriminator that obtains a two-dimensional composition distribution by energy analysis is used to discriminate a charge amount corresponding to X-ray energy.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. One embodiment of the present invention is shown in FIG.
As shown in FIG. The present embodiment is applied to a metal heating device used for vacuum deposition or the like. That is, a crucible 3 containing a molten metal sample 4 is arranged in the vacuum vessel 34, and an electron gun 1 for irradiating the sample 4 with the electron beam 2 in a curved manner is arranged therein. The vacuum 11 is maintained by the vacuum pump 32.

Further, a beryllium window 6 is provided in the vacuum vessel 34.
The X-ray detector 7 is arranged on the atmosphere side 27 from the beryllium window 6. In the present embodiment, the beryllium window 6 is used. However, instead of the beryllium window 6, another window having high X-ray transmittance can be used. The X-ray detector 7 converts the wavelength information of the characteristic X-ray 5 generated from the sample 4 into a voltage pulse height. That is, as shown in FIG. 2, the X-ray detector 7 includes a charge-coupled device (CCD: Charge Coupled Device) in a vacuum vessel 18 maintained in a vacuum 11.
ice) 14 is held in a jig 15 and a vacuum container 18
A window 13 is attached to the front of the device, and a pinhole 12 is arranged in front of the window 13.

The pinhole 12 focuses the characteristic X-rays 5 on the light receiving surface of the solid-state imaging device 14. Instead of the pinhole 12, another X-ray imaging system such as an X-ray mirror is used. May be. In the jig 15 holding the charge-coupled device 14, a cooling pipe 16 for flowing a cooling medium 17 is built in to reduce noise of the solid-state imaging device 14 and improve element analysis accuracy.

Since the vacuum is maintained in the vacuum container 18, the cooling effect of the solid-state imaging device 14 is further enhanced.
The charge coupled device 14 has not only energy resolution but also positional resolution. Therefore, the charge-coupled device 14 sequentially transfers the charges generated by the incident X-rays, thereby obtaining information indicating the planar shape of the density distribution on the irradiation surface included in the X-rays and the elements of the elements on the irradiation surface. The wavelength information corresponding to the type is converted into a time-series voltage pulse wave height and output to the wave height discriminator 33.

If the depletion layer of the charge-coupled device 14 is made thicker, the detection sensitivity to the characteristic X-ray 5 can be improved. The wave height discriminator 33 is a wave height (wavelength) of a specific type.
The image processing device 8 performs image processing on the sampled wave height of the extracted characteristic type and outputs the processed wave height to the monitor 9.

Therefore, the sample 4 is irradiated with the electron beam 2, and the characteristic X-rays generated from the irradiation surface 10 of the sample 4 pass through the beryllium window 6 and exit to the atmosphere side 27, An image is formed on the light receiving surface 14. Then, the information indicating the planar shape of the density distribution on the irradiation surface included in the characteristic X-rays 5 and the wavelength information corresponding to the type of the element on the irradiation surface are stored in the time-series voltage by the charge-coupled device 14. The pulse height is converted to a pulse height and output to the pulse height discriminator 33,
3, only a specific wave height (wavelength) is extracted and output to the monitor 9 via the image processing device 8.

For this reason, the monitor 9 displays the electron beam 2 on the sample 4.
A two-dimensional image of the irradiated surface 10 is projected, and the composition distribution of the material within the range is instantaneously displayed. In the above embodiment, the charge-coupled device 14
However, the present invention is not limited to this. Instead of the charge-coupled device 14, a BBD (Bucket Briga
de Device), CID (Charge Injection Device), MO
S-FET (Metal Oxide Semiconductor-Field Effect
Transistor) and other two-dimensional solid-state imaging devices can also be used.

Another embodiment of the present invention is shown in FIGS.
In the embodiment shown in FIG. 3, the pinhole 12 and the window 13 are integrated and simplified. Other configurations are the same as those of the above-described embodiment shown in FIG. 2, and have the same effects.

The embodiment shown in FIG.
In addition, the distance between the pinhole 12 and the charge-coupled device 14 can be changed by combining a flexible tube 19 with the above. For this reason, in this embodiment, the magnification can be made variable, but the other configuration is the same as that of the above-described embodiment, and has the same effect.

In the embodiment shown in FIG. 5, the charge-coupled device 14 is cooled by an electronic cooling device 28. Because of this,
In the present embodiment, the vacuum vessel 18 can be miniaturized,
A great cooling effect can be obtained.

[0019]

As described above in detail with reference to the embodiments, the present invention utilizes a two-dimensional solid-state image pickup device, so that a two-dimensional solid-state image sensor can be used to perform a planar composition analysis without scanning. It is now possible to do it. For example, 100cm
A large area of ^{2 to} 10000 cm ² can be analyzed, and it can be applied as in-line analysis in a production line.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram in which a surface analyzer according to one embodiment of the present invention is applied to a particle beam application product.

FIG. 2 is a cross-sectional view illustrating an example of an X-ray detector used in a surface analyzer.

FIG. 3 is a cross-sectional view illustrating an example of an X-ray detector used in the surface analyzer.

FIG. 4 is a cross-sectional view illustrating an example of an X-ray detector used in the surface analyzer.

FIG. 5 is a cross-sectional view showing an example of an X-ray detector used for a surface analyzer.

FIG. 6 is a principle diagram showing a component composition analysis according to a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electron gun 2 Electron beam 3 Crucible 4 Sample 5 Characteristic X-ray 6 Beryllium window 7 X-ray detector 8 Image processing device 9 Monitor television 10 Irradiation surface 11 Vacuum 12 Pinhole 13 Window 14 Solid-state image sensor 15 Jig 16 Cooling pipe 17 Cooling fluid 18 Vacuum container 19 Flexible tube 20 Electron gun 21 Focusing coil 22 Electron beam scanning deflection plate 23 Scanning 24 Container 25 Spectral crystal 26 X-ray detector 27 Atmosphere 28 Electronic cooling device 29 Scanning scanning circuit 30 Preamplifier 32 Vacuum pump 33 discriminator 34 vacuum container

Continuation of the front page (56) References JP-A-5-346412 (JP, A) JP-B-3-22582 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01N 23 / 00-23/227

Claims (1)

(57) [Claims] 1. An apparatus for irradiating a sample with an electron beam or an ion beam in a vacuum vessel to perform beam processing such as heating, melting, evaporation and injection, and transmitting a characteristic X-ray generated from the irradiated surface of the sample. Is provided in the vacuum vessel, and a two-dimensional solid-state imaging device having energy resolution and positional resolution is arranged closer to the atmosphere than the window, while X-rays that form a characteristic X-ray transmitted through the window are formed on the solid-state imaging device. provided Sen'yui imaging system, further real output from the solid-state imaging device
A surface analyzer comprising a discriminator for performing energy analysis in a timely manner and obtaining a two-dimensional composition distribution simultaneously with the beam processing .