JPH0340352A - Complex scan type tunnel microscope - Google Patents

Abstract

PURPOSE:To have specification of the STM probe position by placing a standard specimen for alignment on a stage together with the measurement data. CONSTITUTION:There is a precision mount ring 3 at the stage part 2, and there are recessed mounts in the same shape at the tunnel unit part 1 and a small-sized metal microscope. The center of gravity in the plane direction of an optical microscope and the tunnel unit part 1 shall lie in the center of the support 3 point, and the load shall be equally dispersed at the support 3 point even though the tunnel unit 8 and optical microscope are replaced. Then the probe 10 position of STM is aligned with the cross cursor position of the optical microscope, and the standard specimen is measured by the STM, and coordinates are read from the image obtained from this measurement. Then the optical microscope is placed on the mount, and cross cursor of the optical microscope is moved to the place with the obtained coordinates of the STM image. Then the standard specimen is replaced with the measuring specimen, while the optical microscope unit is replaced with the STM unit, and thus STM measurement is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a compound scanning tunneling microscope that combines a scanning tunneling microscope and an optical microscope and facilitates the specification of an STM probe.

[Summary of the invention]

The STM is structured so that it can be separated into a unit part (Z coarse movement, PZT, probe) and a stage part (xy stage, vibration isolating table, sample holder), and the stage part has a unilateral part and a precise mounting mechanism at the connection part. The position reproducibility due to attaching and detaching the unit part was set to about ±1μ.On the other hand, an optical microscope is used as an auxiliary observation means, and it has the same mount as the unit part, so even if the unit and optical microscope are replaced, the difference between the two The position repeatability was approximately ±1μ.Also, a cross cursor was placed on the eyepiece of the optical S!i'i microscope to specify the STM probe position.
.

A movable mechanism was installed on the y. On the other hand, the location on the sample stage can be identified within the STM scanning area (approximately 10μ). It has a standard sample with a specific pattern.

[Conventional technology]

Conventional STM uses a stereomicroscope with a long operating distance (approximately 10 efi) as a means of observing the positional relationship between the sample and the probe, and observes the sample surface from diagonally above.

Since the sample surface is observed from an oblique angle, it is not possible to image the entire surface of the sample at a -degree angle, and since a stereomicroscope is used, the magnification is only 200 times and the resolution is only about 10μ, making it difficult to see the minute spots on the sample. It was difficult to align.

[Problem to be solved by the invention]

Although the 37M device has a resolution that allows observation at the atomic level, its scanning area is narrow, at most about IOμ. Therefore, in order to measure the part of the sample to be observed using STM, it is necessary to align the sample or the probe to this 10μ scanning area. As mentioned above, when the sample surface is viewed from an oblique angle using a solid W4 microscope, the entire surface of the sample is not in focus, and both magnification and resolution are low. The present invention has been made to solve this problem, and the optical microscope is attached to a mount having the same structure as the tunnel unit of the STM. Even if you replace the mirror and tunnel unit,
The positional repeatability with the stage part is about ±lμ, and S
The object of the present invention is to provide a 37M device that enables specification of the TM probe position.

[Means to solve the problem]

The main means adopted by the present invention to achieve the above object are as follows. That is, (1) It consists of a scanning tunneling microscope lens barrel and an optical microscope lens barrel equipped with the same type of mount mechanism, and a stage section equipped with a mount mechanism that connects to the mount mechanism, and the stage section is equipped with a standard sample for positioning. A compound scanning tunneling microscope characterized in that a compound scanning tunneling microscope is placed together with a measurement sample.

(2) The compound scanning tunneling microscope according to claim 1, further comprising a cross cursor xy moving mechanism provided in the eyepiece section of the optical W4 lens barrel.

[Effect]

Optical glI mounted on a mount with the same structure as the tunnel unit.
Even if a microscope is attached and the optical microscope and tunnel unit are replaced, the positional repeatability with the stage part is about ±lμ,
On the other hand, the eyepiece of the optical microscope was equipped with a mechanism that could move the cross cursor in x and y directions, making it possible to specify the position of the STM probe.

By using the above method, the sample surface can be observed at a shorter working distance than in the vertical direction, so it can be used as an optical microscope at high magnification (1000
It becomes possible to observe the sample surface with a high resolution (approximately 0.5μ). In addition, the entire surface of the sample is in focus, allowing observation of sample shapes as fine as about 1 μm.

On the other hand, to align the 37M probe and the sample, perform a 10μ scan of the standard sample mentioned above with STM, display an image of the characteristic shape, and replace the tunnel unit and optical mirror. , find which part of the standard sample was scanned by the STM image, and move the cross cursor on the eyepiece to that position to find the STM probe position. Observe the zero-order measurement sample with an optical microscope, and Move the measurement point to the cursor position. Replace the optical microscope and tunnel unit 7 again to obtain an STM image. Therefore, a mount is required that has a positional reproducibility of approximately ±1 μ even when the optical microscope and tunnel unit are replaced.

〔Example〕

FIG. 1 shows a conceptual diagram of an embodiment of the present invention. This device is
The stage section 2, which consists of a tunnel unit section 1, a stage section 2, and a small metallurgical microscope (FIG. 4), has a precision mount ring 3 and a convex section 4. Although not shown, the tunnel unit part 1 and the small metallurgical microscope have a recessed mount having the same shape. Fig. 2 shows an example of a precision mount protrusion. Support the load at a point. On the other hand, the recess is shown in Figure 3 +8
) ~tc> 5.6. Consists of 7. 5 regulates the vertical height, 6 regulates the rotation direction, and 7
The radial direction is restricted by Moreover, the same effect was obtained even when only three shapes 6 were arranged in the radial direction. In addition, in order to further increase the accuracy of alignment, the shapes 6 are arranged in the M radial direction and are arranged so as to taper toward the center of the ring. Naturally, the same effect can be obtained by replacing the convex and concave portions of the mount, but when assembling the apparatus in a vertical direction, it is advantageous for the stage section 2 to have a convex portion because less dust and the like will accumulate there. Also, the center of gravity of the tunnel unit 1 and the optical 'JA6'& mirror in the plane direction should be at the center of the three support points, so that even if the tunnel unit 8 and the optical microscope are replaced, the center of gravity in the plane direction will remain at the three support points. The load movement was distributed equally. With the above-mentioned mounting mechanism, the position repeatability is about ±1 μ when the tunnel unit 8 and the optical microscope are placed on the stage section 2, and the STM scanning area is 10
Since there is μ, S to the specified sample position under the field of view of the optical microscope.
It becomes possible to guide the TM probe.

Figure 4 shows the cross cursor 9 with an x and y movement mechanism attached to the eyepiece of an optical ni microscope.The movement resolution of the cross cursor is 10μ, and when a 40x objective lens is used, the resolution at the sample surface is 0.25μ. This makes it possible to specify the position, and the accuracy is sufficient considering the positioning accuracy of ±1μ.

Next, we will show how to align the STM probe 10 position with the optical microscope cross cursor position. An example of the alignment reference sample shown in FIG. 5 is divided by meshes for each IOμ, and the coordinates of the locations are shown inside the meshes.

Written with letters or numbers. This standard sample is measured by STM, and the coordinates are read from the image.The zero-order optical microscope is placed on the mount and the cross cursor of the optical microscope is moved to the coordinates where the STM image is obtained. This cross cursor position is the 0th order mark which becomes the STM probe position! 1! The sample and the measurement sample are exchanged, and the 0-order optical microscope unit and the STM unit are exchanged, and the STM measurement is performed by sending the sample on a stage or the like so that the observation area of the sample coincides with the cross cursor position.

〔Effect of the invention〕

As a result of the configuration described above, it is possible to move the sample to any position within ±1μ.
It has become possible to align the STM probe with a certain degree of precision. In addition, since the sample can be observed from the vertical direction, it has become possible to observe the sample with high magnification and high resolution using a metallurgical microscope.

[Brief explanation of drawings]

FIG. 3 is an explanatory diagram of the convex part, FIG. 3 is an explanatory diagram of the precision mount concave receiver used in an embodiment of the present invention, FIG. 4 is a diagram showing an optical microscope used in an embodiment of the present invention, and FIG. It is a figure which shows an example of the standard sample for alignment used in one Example.・Tunnel uni-node section ・Stage section ・Tight mount ring ・Convex part receiver ・Tunnel uni-soto ・Optical microscope eyepiece ・Probe ・Sample tight movement stage and above Supplier Seiko Electronics Industries, Ltd.

Claims (2)

[Claims] (1) Consists of a scanning tunneling microscope barrel and an optical microscope barrel equipped with the same type of mount mechanism, and a stage section equipped with a mount mechanism that connects to the mount mechanism, and the stage section is equipped with a standard sample for positioning to be measured. A compound scanning tunneling microscope characterized by being placed together with a sample. (2) Cross cursor x on the eyepiece of the optical microscope lens barrel above.
2. The compound scanning tunneling microscope according to claim 1, further comprising a y-moving mechanism.