JPH0326902A - Scanning-type tunnel microscope - Google Patents

Abstract

PURPOSE:To easily change a sample when using a microscope by a method whereby a sample holder and a probe unit are changed by an exchange rod which is set movable along an axis connecting said probe unit and sample. CONSTITUTION:When a sample S is observed by a microscope, assuming that an axis connecting a probe 7 and the sample S is an axis Z, an exchange rod 10 is inserted in a movable manner along the Z axis. A chuck 11 is provided at an end portion of the exchange rod 10 for holding a sample holder 9 and a probe socket 6. In order to exchange the probe socket 6, the socket 6 held by the chuck 11 is moved to an end portion of a prove driving mechanism 5 through an opening portion of a sample stage 8 and screwed to the mechanism 5 by rotating the exchange rod 10. In order to exchange the sample holder 9, the sample holder 9 held by the chuck 11 is fitted into the opening portion of the sample stage 8 by the exchange rod 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a scanning tunneling microscope that detects a tunneling current by bringing a probe close to a sample and outputs an image of irregularities on the surface of the sample.

[Prior Art and Problems to be Solved by the Invention In a J-scanning tunneling microscope, it is required that the tip of the probe be sharpened in order to obtain atomic-level resolution of the surface of an observation sample. Therefore, the tip of the probe is a one-atom tip, such as one atom at the tip of the probe formed by an electric field polishing method or the like.

Now, when viewing a sample using a scanning tunneling microscope,
In order to obtain a tunneling current between the tip of the probe and the surface of the sample, it is necessary to bring the tip of the probe and the surface of the sample close to about 1 nm, but during this approach, the sample and the surface of the sample must be brought close to each other. The atomic tip of the probe may be damaged due to contact with the tip of the probe, or
Or the sample may be damaged. like this,
Since atomic-level resolution cannot be obtained with a probe with a damaged atomic tip, it must be replaced with a normal probe. Also,
Even if the sample is damaged, it must be replaced with a normal sample.

However, the problem is that replacing such a minute probe requires skill. In addition, breaking the vacuum of the ultra-high vacuum chamber in which the tunneling microscope is housed to replace the probe and sample is problematic because it takes a huge amount of time to perform re-observation after replacing the probe and sample. It is said that

The first aspect of the present invention takes the above-mentioned problems into consideration and aims to provide a scanning tunneling microscope in which the probe can be easily replaced.

A second object of the present invention is to provide a scanning tunneling microscope that allows easy exchange of probes and samples.

[Means for Solving the Problems] A first aspect of the present invention provides a scanning tunneling microscope that detects tunneling current by bringing a probe close to a sample and driving it three-dimensionally to detect a tunnel current. In a scanning tunneling microscope, the scanning tunneling microscope is equipped with a probe unit to which a probe is detachably attached to the piezoelectric element drive mechanism, and a holding mechanism for holding the sample; When the axis connecting the sample is called the Z-axis, an exchange rod for exchanging the probe unit is provided movably along the Z-axis, and a mechanism is provided for removing the sample from the two axes at the time of exchange. It is characterized by having the following.

A second aspect of the present invention provides a scanning tunneling microscope that detects tunneling current by bringing a probe close to a sample and driving it in three dimensions, including a piezoelectric element drive mechanism that drives the probe, and a piezoelectric element drive mechanism that is detachable from the piezoelectric element drive mechanism. A probe unit to which a probe is fixed, a sample holder that holds the sample, and a sample stage to which the sample holder is mounted are provided, and the probe unit and sample are connected during microscopic examination. When the axis connecting the two is called the Z axis, an exchange rod for chucking the sample holder and the probe unit is provided movably along the Z axis,
It is characterized in that the sample holder and probe unit are exchanged on the Z-axis using the exchange rod.

[Example] Hereinafter, an example of the present invention will be described based on the drawings. 1st
The figure is an apparatus configuration diagram for explaining one embodiment of the present invention, and FIGS. 2 and 3 are enlarged views of main parts.

In FIG. 1, 1 is an observation chamber, 2 is a preliminary chamber, 3 is a gate valve, 4 is a base, 5 is a probe drive mechanism, 6 is a probe socket to which a probe 7 is fixed, 8 is a sample stage, 9 is a sample holder;
10 is a replacement rod, 11 is a chuck, 12 is a vibration isolator, and S is a sample.

The inside of the observation chamber 1 and the inside of the preliminary chamber 2 are evacuated to a high vacuum or ultra-high vacuum state by an exhaust device (not shown). A base 4 is placed on a vibration isolator 12 in the observation chamber 1, and a probe drive mechanism 5 and a sample stage 8 are placed on the base 4.

A male screw portion 5a is provided at the tip of the probe drive mechanism 5, and the probe socket 6 is screwed into the male screw portion 5a.

Further, the sample stage 8 is provided with an opening 8a, and the sample holder 9 is fitted into the opening 8a.

Here, the axis connecting the probe unit and the sample during microscopic examination, that is, the height direction of the probe 7 and the surface of the sample S is Z.
direction (Z-axis), an exchange rod 10 that is movable along the Z-axis is inserted. A chuck 11 for holding a sample holder and a probe socket is provided at the tip of the exchange rod 10. Here, FIG. 2 shows a state in which the probe socket 6 is held by the chuck 11. As shown in FIG. 2, the chuck 11 at the tip of the exchange rod 10 is provided with a holding part consisting of a spring leaf 14 that holds down the roller 13 and the shaft 13a of the roller, and the probe socket 6 is held by the holding part. has been done.

In addition, in FIG. 3, the sample holder 9 is held by the chuck 11.
is shown in a state where it is maintained.

As shown in FIG. 3, a female screw portion 15 is provided inside the chuck l1 at the tip of the exchange rod 10. The sample holder 9 is held by the female screw part 15 and the male screw part 16 provided on the sample holder 9 screwed together.

The replacement (installation) work of the probe socket and sample holder will be explained below.

First, when replacing the probe socket, the probe socket 6 held by the chuck 11 is moved through the opening 8a of the sample stage 8 to the tip of the probe drive mechanism 5. Then, by rotating the exchange rod 10, the probe socket 6 is screwed and fixed to the male screw part 5a provided at the tip of the drive mechanism 5. After the probe socket 6 is fixed, the replacement rod 10 is pulled back to the preliminary chamber 2. Then, the gate valve provided between the observation chamber 1 and the preliminary chamber 2 is closed, and the sample holder 9 is placed in the exchange rod on the preliminary chamber 2 side.
can be installed. After the interior of the preliminary chamber 2 is evacuated to a high vacuum or ultra-high vacuum state by an exhaust device (not shown), the gate valve 3 is opened.

Next, when replacing the sample holder, the sample holder held by the chuck 11 is moved to the opening 8a of the sample stage 8 by the exchange rod 10 and fitted into the opening 8a. The sample holder 9 is fixed to the stage 8 by a fixing mechanism (not shown) such as a fixing bottle provided on the sample stage 8. Thereafter, the replacement rod]O is pulled back to the preliminary chamber 2.

Note that when removing the probe socket 6 from the probe drive mechanism 5 and when removing the sample holder 9 from the sample stage 8, the above-mentioned operations may be performed in the reverse order.

The present invention is not limited to the embodiments described above, but can be implemented with modifications.

For example, in the above-mentioned embodiment, the sample stage 8 is provided with an opening 8a for passing the exchange rod, and the sample stage 8 is provided with an opening 8a for passing the exchange rod, so as not to prevent the exchange rod from reaching the probe when exchanging the probe socket. However, the sample stage 8 is configured to be rotatable around an axis parallel to the Z-axis, and when replacing the probe socket, the sample stage is rotated and removed from the Z-axis. It may be configured to remove the sample.

[Effects of the Invention] As is clear from the above description, in the first invention, when the axis connecting the probe unit and the sample during microscopic examination is called the Z axis, the probe unit is replaced. According to the present invention, the exchange rod is provided movably along the Z-axis, and the exchange rod is provided with a mechanism for removing the sample from the Z-axis. It can be done easily.

Further, in a second aspect of the present invention, a piezoelectric element driving mechanism for driving the probe, a probe unit to which a probe is fixed and detachably provided to the piezoelectric element driving mechanism, and a probe unit for holding the sample are provided. In addition to providing a sample holder and a sample stage on which the sample holder is mounted, when the axis connecting the probe unit and the sample during microscopic examination is referred to as the Z axis, exchange for chucking the sample holder and the probe unit. By providing a rod movable along the Z-axis and exchanging the sample holder and probe unit on the Z-axis with the exchange rod,
It becomes possible to easily exchange the probe and sample.

Therefore, even an inexperienced operator can easily exchange minute probes and samples in a short period of time.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the configuration of an apparatus for explaining an embodiment of the present invention, Fig. 2 is a diagram showing a state in which a probe socket is held by a chuck, and Fig. 3 is a diagram showing a state in which a sample holder is held by a chuck. It is a diagram. 1: Observation chamber 2: Preliminary chamber 3: Gate valve 4: Base 5: Probe drive mechanism 6: Probe socket 7: Probe 9: Sample holder 11: Chuck 13: Roller 15: Female screw part S: Sample 8 10 12 14 16 : Sample stage: Replacement rod: Vibration isolator: Spring leaf: Male screw part

Claims (1)

[Claims] 1. In a scanning tunneling microscope that detects tunneling current by bringing a probe close to a sample and driving it in three dimensions, a piezoelectric element drive mechanism that drives the probe; In a scanning tunneling microscope equipped with a probe unit to which a removably attached probe is fixed and a holding mechanism for holding the sample, the axis connecting the probe unit and the sample during microscopic examination is the Z axis. When called, it is characterized in that a replacement rod for replacing the probe unit is provided movably along the Z-axis, and a mechanism is provided for removing the sample from the Z-axis at the time of replacement. Scanning tunneling microscope. 2. In a scanning tunneling microscope that detects tunneling current by bringing a probe close to a sample and driving it three-dimensionally, a piezoelectric element drive mechanism that drives the probe, and a piezoelectric element drive mechanism that is removably attached to the piezoelectric element drive mechanism are provided. A probe unit to which a probe is fixed, a sample holder that holds the sample, and a sample stage to which the sample holder is mounted are provided, and an axis connecting the probe unit and the sample during microscopic examination is Z. When referred to as the axis, an exchange rod for chucking the sample holder and probe unit is provided movably along the Z-axis, and the sample holder and probe unit are exchanged on the Z-axis by the exchange rod. A scanning tunneling microscope.