JP3968436B2 - Auger photoelectron coincidence spectrometer and Auger photoelectron coincidence spectroscopy - Google Patents

Description

  The present invention relates to an Auger photoelectron coincidence spectrometer and Auger photoelectron coincidence spectroscopy.

  An Auger photoelectron coincidence spectrometer is generally manufactured by combining two electron energy analyzers. For example, (1) two concentric hemispherical analyzers (HWHaak et al., Rev. Sci. Instrum. 55 (1984) 696) and (2) two bubble path cylindrical mirror analyzers (E. Jensen et al. Rev. Sci. Instrum. 63 (1992) 3013), or (3) two 127 ° concentric cylinder analyzers (S. Thurgate et al., Rev. Sci. Instrum. 61 (1990) 3733) A combination was proposed.

  However, the analyzers (1) to (3) described above have a problem that the detection efficiency of the Auger photoelectron coincidence signal is low because the solid angle is small. There is also a problem that it is difficult to adjust the position of the two analyzers. Furthermore, since a dedicated ultra-high vacuum chamber is required and the manufacturing cost of these analyzers is high, there is a problem that the Auger photoelectron coincidence spectrometer as a whole is expensive.

  An object of the present invention is to provide a novel Auger photoelectron coincidence spectrometer and Auger photoelectron coincidence spectroscopy which can detect Auger photoelectron coincidence easily and inexpensively with high efficiency.

In order to achieve the above object, the present invention provides:
A cylindrical first inner electrode, a first outer electrode arranged concentrically with the first inner electrode, and a center of these electrodes behind the first inner electrode and the first outer electrode A coaxial symmetric mirror electron energy analyzer including an electron detector disposed on an axis;
The coaxial symmetric mirror electron energy analyzer has a cylindrical second inner electrode, a second outer electrode arranged concentrically with the second inner electrode, and the second inner electrode disposed in the inner electrode. A miniature cylindrical mirror electron energy analyzer comprising an electron multiplier located behind the inner electrode and the second outer electrode;
The present invention relates to an Auger photoelectron coincidence spectrometer.

  In the miniature cylindrical mirror electron energy analyzer, for example, the outer diameter of the second inner electrode can be 11 mm or less, the inner diameter of the second outer electrode can be 24 mm or less, and the entire outer diameter can be 26 mm or less. That is, the miniature cylindrical mirror electron energy analyzer should be smaller than the conventional cylindrical mirror electron energy analyzer (Rev. Sci. Instrum. 69 (1998) 3805) having an outer diameter of 30 mm. Can do.

  Therefore, the position adjustment between the coaxial symmetric mirror electron energy analyzer and the miniature cylindrical mirror electron energy analyzer can be easily performed by using an xyz position adjusting mechanism and a tilt adjusting mechanism.

  Further, as the miniature cylindrical mirror electron energy analyzer is miniaturized, the entire Auger photoelectron coincidence spectrometer can be miniaturized, so that the spectrometer can be mounted in a multipurpose ultra-high vacuum chamber. Furthermore, the configuration of the entire Auger photoelectron coincidence spectrometer is simplified. As a result, the manufacturing cost of the entire spectrometer can be reduced.

  In addition, the miniature cylindrical mirror electron energy analyzer has a solid angle of 0.72 sr or more, which is sufficiently larger than a conventional cylindrical mirror electron energy analyzer. Therefore, the Auger photoelectron coincidence spectrometer of the present invention having such an analyzer can detect a wide range of Auger electrons and can detect the target Auger photoelectron coincidence signal with high efficiency.

  Further, by using the above-described Auger photoelectron coincidence spectrometer, the Auger photoelectron coincidence spectroscopy of the present invention can be provided.

  As described above, according to the present invention, it is possible to provide a novel Auger photoelectron coincidence spectrometer and Auger photoelectron coincidence spectroscopy that can detect Auger photoelectron coincidence easily and inexpensively.

  Hereinafter, other features and advantages of the present invention and Auger photoelectron coincidence spectroscopy using the above-described Auger photoelectron coincidence spectrometer will be described in detail.

  FIG. 1 is a block diagram showing an example of an Auger optoelectronic coincidence spectrometer according to the present invention. An Auger photoelectron coincidence spectrometer 10 shown in FIG. 1 includes a coaxial symmetrical mirror electron energy analyzer 20 and a miniature cylindrical mirror electron energy analyzer 30 concentrically incorporated therein.

  The coaxial symmetric mirror electron energy analyzer 20 includes a first inner electrode 21 having a cylindrical shape and a first outer electrode 22 having a cylindrical shape. The inner electrode 21 and the outer electrode 22 are arranged so as to be coaxial on the central axis AA line of the coaxial symmetric mirror electron energy analyzer 20 passing through the internal space formed by these electrodes. Further, an electron detector 23 is disposed behind the first inner electrode 21 and the first outer electrode 22 on the central axis AA. In addition, a disc-shaped auxiliary electrode 24 is provided in front of and behind the first inner electrode 21 and the first outer electrode 22 so as to cover the end portion excluding the central portion.

  The first inner electrode 21 has a mesh shape. The electron detector 23 can be composed of, for example, MCP (Hamamatsu Photonics, F4655).

  The miniature cylindrical mirror electron energy analyzer 30 includes a cylindrical second inner electrode 31 and a cylindrical second outer electrode 32. The inner electrode 31 and the outer electrode 32 are arranged so as to be coaxial on the central axis AA. As a result, as described above, the coaxial symmetric mirror electron energy analyzer 20 and the miniature cylindrical mirror electron energy analysis are performed. The vessels 30 are arranged concentrically with each other. Further, an electron multiplier tube 33 is disposed behind the second inner electrode 31 and the second outer electrode 32 on the central axis AA.

  A sample S to be measured is arranged on the central axis A-A in front of the coaxial symmetrical mirror electron energy analyzer 20 and the miniature cylindrical mirror electron energy analyzer 30.

  In the Auger photoelectron coincidence spectrometer 10 shown in FIG. 1, the potential of the first inner electrode 21 of the coaxial symmetric mirror electron energy analyzer 20 is maintained at 0 V, and the second inner electrode 31 of the miniature cylindrical mirror electron energy analyzer 30 is maintained. Is also maintained at 0V. The first outer electrode 22 and the auxiliary electrode 24 of the coaxial symmetric mirror electron energy analyzer 20 and the second outer electrode 32 of the miniature cylindrical mirror electron energy analyzer 30 are externally controlled by an external control circuit described later. A stable electric field for efficiently introducing photoelectrons to be measured into the coaxial symmetrical mirror electron energy analyzer 20 and efficiently introducing Auger electrons to be measured into the miniature cylindrical mirror electron energy analyzer 30. In order to form each, a predetermined voltage can be applied.

  In the miniature cylindrical mirror electron energy analyzer 30, the outer diameter of the second inner electrode 31 can be 11 mm or less, the inner diameter of the second outer electrode 32 can be 24 mm or less, and the entire outer diameter can be 26 mm or less. In other words, the miniature cylindrical mirror electron energy analyzer 30 should be smaller than the conventional cylindrical mirror electron energy analyzer (Rev. Sci. Instrum. 69 (1998) 3805) having an outer diameter of 30 mm. Can do.

The Auger photoelectron coincidence spectrometer 10 includes an xyz position adjustment mechanism, a tilt adjustment mechanism, and the like (not shown). When the coaxial symmetric mirror electron energy analyzer 20 and the miniature cylindrical mirror electron energy analyzer 30 are arranged on the central axis AA, the knife edge type metal seal flange is placed on the central axis AA via the tilt adjusting mechanism. And can be obtained by combining the analyzers 20 and 30 together on the knife-edge metal seal flange .

  As described above, the miniature cylindrical mirror electron energy analyzer 30 is sufficiently miniaturized. By using the xyz position adjustment mechanism, the tilt adjustment mechanism, and the like, the coaxial symmetric mirror electron energy analyzer 20 and the miniature cylindrical mirror electron energy analysis are performed. Position adjustment between the containers 30 can be easily performed. Specifically, the position can be adjusted in about 10 minutes.

  Further, as the miniature cylindrical mirror electron energy analyzer 30 is reduced in size, the entire Auger photoelectron coincidence spectrometer 10 can be reduced in size, so that the spectrometer 10 can be mounted in a multipurpose ultra-high vacuum chamber. Furthermore, the configuration of the entire Auger photoelectron coincidence spectrometer 10 is simplified. As a result, the manufacturing cost of the spectroscope 10 as a whole can be reduced.

  Further, the miniature cylindrical mirror electron energy analyzer 30 has a sufficiently large solid angle of 0.72 sr or more as compared with a conventional cylindrical mirror electron energy analyzer or the like. Accordingly, the Auger photoelectron coincidence spectrometer 10 having such an analyzer 30 can detect a wide range of Auger electrons, and can detect a target Auger photoelectron coincidence signal with high efficiency.

  Next, a method for detecting an Auger photoelectron coincidence signal using the Auger photoelectron coincidence spectrometer 10 shown in FIG. 1 will be described.

  As described above, the Auger photoelectron coincidence spectrometer 10 and the sample S shown in FIG. 1 are arranged in a predetermined multipurpose ultra-high vacuum chamber. Next, as shown in FIG. 1, the radiated light R is incident on the sample S at an angle of 84 °, for example. At this time, the photoelectron X and the Auger electron Y are emitted from the sample S, and the photoelectron X flies through the coaxial symmetrical mirror electron energy analyzer 20 and is detected by the electron detector 23. On the other hand, Auger electrons Y fly through the miniature cylindrical mirror electron energy analyzer 30 and are detected by the electron image multiplier 33.

  The signal of the photoelectron X detected by the electron detector 23 is amplified by the amplifier 41 and then introduced to the trigger side of the multichannel scaler 46 via the discriminator 42. On the other hand, the signal of the Auger electron Y detected by the electron image multiplier 33 is amplified by the amplifier 43, passes through the discriminator 44, and passes through the delay device 45, whereby the signal of the photoelectron X is predetermined. Introduced to the input side of the multi-channel scaler 46 with a time delay.

  At this time, when the signal of the Auger electron Y is triggered by the signal of the photoelectron X in the multi-channel scaler 46, an Auger electron signal derived from the emission process of the photoelectron X, that is, an Auger photoelectron coincidence signal can be obtained. The spectrum related to the Auger photoelectron coincidence signal can be obtained, for example, by graphing the time difference of flight of the photoelectron X and Auger electron Y as a parameter. Such graphing is automatically performed in the computer 47 by transmitting a predetermined electrical signal from the multi-channel scaler 46 to the computer 47.

  It should be noted that a predetermined control signal is supplied from the computer 47 to the power supply 48, whereby the first detection of the coaxial symmetric mirror electron energy analyzer 20 is performed so that the detection of the above-mentioned Auger photoelectron coincidence signal is always in an optimum state. The electric potential of the outer electrode 22 and the second outer electrode 32 of the miniature cylindrical mirror electron energy analyzer 30 can be adjusted.

  Using a Si single crystal as the sample S, p-polarized radiated light is incident on the (111) plane of the Si single crystal at an angle of 84 ° to obtain Si2p photoelectrons and SiLVV Auger electrons. The resulting signal was obtained. Next, the Si2p photoelectron signal was amplified and then introduced into the trigger side of the multichannel scaler, and the SiLVV Auger electron signal was amplified and delayed by about 2 μs and introduced into the input side of the multichannel scaler.

  Thereafter, the signal of the SiLVV Auger electrons was triggered by the signal of the Si2p photoelectrons to obtain an Auger photoelectron coincidence signal. FIG. 2 shows a graph of the Auger photoelectron coincidence signal with respect to the time-of-flight difference between the Si2p photoelectron and the SiLVV Auger electron.

  As apparent from FIG. 2, the Auger photoelectron coincidence signal was observed at a flight time difference of −64 ns, and it was confirmed that the Auger photoelectron coincidence signal could be observed in an extremely short time of about 120 seconds.

  As described above, the present invention has been described in detail based on the embodiments of the present invention with specific examples. However, the present invention is not limited to the above contents, and all modifications and changes are made without departing from the scope of the present invention. It can be changed.

It is a block diagram which shows an example of the Auger optoelectronic coincidence spectrometer of this invention. It is a spectrum which shows an example of an Auger photoelectron coincidence signal measured using the Auger photoelectron coincidence spectrometer of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Auger photoelectron coincidence spectrometer 20 Coaxial symmetrical mirror electron energy analyzer 21 1st inner electrode 22 2nd outer electrode 23 Electron detector 24 Auxiliary electrode 30 Miniature cylindrical mirror electron energy analyzer 31 2nd inner electrode 32 2nd External electrode 33 Electron image multiplier 41, 43 Amplifier 42, 44 Discriminator 45 Delay device 46 Multichannel scaler 47 Computer 48 Power supply

Claims (21)

A cylindrical first inner electrode, a first outer electrode arranged concentrically with the first inner electrode, and a center of these electrodes behind the first inner electrode and the first outer electrode A coaxial symmetric mirror electron energy analyzer including an electron detector disposed on an axis;
The coaxial symmetric mirror electron energy analyzer has a cylindrical second inner electrode, a second outer electrode arranged concentrically with the second inner electrode, and the second inner electrode disposed in the inner electrode. A miniature cylindrical mirror electron energy analyzer comprising an electron multiplier located behind the inner electrode and the second outer electrode;
An Auger photoelectron coincidence spectrometer characterized by comprising:   The Auger photoelectron coincidence spectrometer according to claim 1, wherein the coaxial symmetric mirror electron energy analyzer and the miniature cylindrical mirror electron energy analyzer are arranged on the same axis. A knife-edge metal seal flange is provided, wherein the coaxial symmetric mirror electron energy analyzer and the miniature cylindrical mirror electron energy analyzer are integrally assembled on the knife-edge metal seal flange. Item 3. An Auger photoelectron coincidence spectrometer according to item 2. The Auger photoelectron coincidence spectrometer according to any one of claims 1 to 3, wherein the first inner electrode has a mesh shape.   The Auger photoelectron coincidence spectrometer according to any one of claims 1 to 4, wherein an outer diameter of the miniature cylindrical mirror electron energy analyzer is 26 mm or less.   The Auger photoelectron coincidence spectrometer according to any one of claims 1 to 5, wherein the solid angle of the miniature cylindrical mirror electron energy analyzer is 0.72 sr or more.   The coaxial symmetric mirror electron energy analyzer efficiently introduces photoelectrons to be measured into the coaxial symmetric mirror electron energy analyzer at at least one end of the first inner electrode and the first outer electrode. And an auxiliary electrode for forming a stable electric field for efficiently introducing Auger electrons to be measured into the miniature cylindrical mirror electron energy analyzer. An Auger photoelectron coincidence spectrometer according to any one of the above.   The Auger photoelectron coincidence spectrometer according to any one of claims 1 to 7, further comprising an xyz position adjusting mechanism.   The Auger photoelectron coincidence spectrometer according to claim 1, further comprising a tilt adjustment mechanism.   10. The Auger photoelectron coincidence spectroscopy according to claim 1, wherein the coaxial symmetric mirror electron energy analyzer detects photoelectrons, and the miniature cylindrical mirror electron energy analyzer detects Auger electrons. vessel.   11. An Auger optoelectronic coincidence spectrometer according to claim 10, comprising a multi-channel scaler for generating an Auger optoelectronic coincidence signal. A cylindrical first inner electrode, a first outer electrode arranged concentrically with the first inner electrode, and a center of these electrodes behind the first inner electrode and the first outer electrode Providing a coaxial symmetric mirror electron energy analyzer including an electron detector disposed on an axis;
A cylindrical second inner electrode, a second outer electrode arranged concentrically with the second inner electrode, and an electron multiplier arranged behind the second inner electrode and the second outer electrode Disposing a miniature cylindrical mirror electron energy analyzer including a double tube within the inner electrode of the coaxial symmetric mirror electron energy analyzer;
Radiation light is incident on a sample provided in front of the coaxial symmetric mirror electron energy analyzer and the miniature cylindrical mirror electron energy analyzer, and the obtained photoelectrons are detected by the coaxial symmetric mirror electron energy analyzer. Detecting the obtained Auger electrons with the miniature cylindrical mirror electron energy analyzer;
Auger photoelectron coincidence spectroscopy characterized by comprising:   The Auger photoelectron coincidence spectroscopy according to claim 12, wherein the coaxial symmetric mirror electron energy analyzer and the miniature cylindrical mirror electron energy analyzer are arranged on the same axis. The Auger photoelectron coincidence spectroscopy according to claim 13, wherein the coaxial symmetric mirror electron energy analyzer and the miniature cylindrical mirror electron energy analyzer are integrally assembled on a knife-edge metal seal flange . The Auger photoelectron coincidence spectroscopy according to any one of claims 12 to 14, wherein the first inner electrode has a mesh shape.   16. The Auger photoelectron coincidence spectroscopy according to any one of claims 12 to 15, wherein an outer diameter of the miniature cylindrical mirror electron energy analyzer is 26 mm or less.   The Auger photoelectron coincidence spectroscopy according to any one of claims 12 to 16, wherein the solid angle of the miniature cylindrical mirror electron energy analyzer is 0.72 sr or more.   The coaxial symmetric mirror electron energy analyzer efficiently introduces photoelectrons to be measured into the coaxial symmetric mirror electron energy analyzer at at least one end of the first inner electrode and the first outer electrode. And an auxiliary electrode for forming a stable electric field for efficiently introducing Auger electrons to be measured into the miniature cylindrical mirror electron energy analyzer. The Auger photoelectron coincidence spectroscopy according to any one of the above.   A multi-channel scaler is prepared, the photoelectron signal is introduced to the trigger side of the multi-channel scaler, the Auger electron signal is introduced to the input side of the multi-channel scaler, and the Auger electron signal is converted into the photoelectron signal. The Auger photoelectron coincidence spectroscopy according to any one of claims 12 to 18, characterized by triggering and detecting the obtained Auger photoelectron coincidence signal.   The Auger photoelectron coincidence spectroscopy according to claim 19, wherein the Auger electron signal is input to the multi-channel scaler with a predetermined time delay from the photoelectron signal.   The Auger photoelectron coincidence spectroscopy according to claim 19 or 20, wherein the Auger photoelectron coincidence signal is detected using a time-of-flight difference between the photoelectrons and the Auger electrons as a parameter.

Images