JPH03210405A - Probe holder - Google Patents

Abstract

PURPOSE:To obtain a probe holder which is light, capable of a connection by a press fit method, dismountable and suitable for a high speed scanning by using a resin material. CONSTITUTION:A holder body 6 is formed by a resin material and a probe 1 is mounted to the top of the holder body 6. A notch 4 helps a press fit and a spring force generated by the press fit fixes the holder body 6. A metallic member 2 for taking a lead from an electrode is connected to the probe 1. Since the weight of the holder body 6 can be reduced and a resonant frequency is increased, a high speed scanning can be performed. Further, since a press fit method can be used for a connection, mounting and dismounting can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a probe holder mechanism used in a scanning tunneling microscope and an apparatus to which the same is applied.

[Prior Art] In recent years, research on scanning tunneling microscopes (STM) has become active. In the STM, since the distance between the sample and the probe is brought close to the order of nanometers, external factors such as vibration often cause the two to come into contact and be damaged, making it unavoidable to replace the probe. In order to exchange such probes, the probes are fixed to these actuators using a jig as shown in Figure 2 to connect them, and only the probe 1 provided at the tip of the electrostrictive element 3 can be replaced. [F, Bebenbacher, E, Laegsga]
ard, ni, Mortensen U, N1elsen,
and 1. Stensgaard: Rev, Sci.
Instruw: vol59(7), July 19
88].

[Problems to be Solved by the Invention] However, in the conventional method, the cylindrical electrostrictive element 3
Because a heavy member is attached to the tip of the probe 1, the moment of inertia of the system (referred to as the scanning head) that combines the electrostrictive element and probe 1 increases, and the resonance frequency decreases, making high-speed scanning difficult. Since the needle-shaped probe must be replaced directly using a bottle set, it is difficult to handle and the probe is often damaged due to installation mistakes.

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a probe holder that has a simple structure, is lightweight, and enables high-speed scanning and highly reliable scanning.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention creates a probe holder using resin, and the spring mechanism or the uneven portion is formed by combining only the probe holder or the probe holder and a cylindrical electrostrictive element. Both are installed inside.

[Function] The structure of the present invention reduces the element weight, and since a spring type or uneven connection reinforcement method is adopted, the resonant frequency approaches the resonant frequency of the element itself, and high-speed scanning becomes possible. The mechanism allows the holder and probe to be exchanged, making it easier to handle, improving operability and making sample observation easier.

[Example] FIGS. 1(a) to 1(d) are schematic diagrams showing different examples of probe holders according to embodiments of the present invention. On each side, the holder body 6 is formed of a resin material;
A probe 1 is attached to the upper part of the probe. (a) and (b) are types in which a notch 4 is provided to assist press-fitting, and the resulting spring force is used to fix the product. (C) and (d) are types in which the convex portion 5 is provided on the holder main body 6 side and fixed. The convex portion 5
The cylindrical electrostrictive element may be provided with a recess that fits into the cylindrical electrostrictive element. The shaded area 2 in the figure is a metal member for taking out the electrode. In this embodiment, polycarbonate is used as the resin material to form the shape shown in the figure. Then, this holder main body 6 is press-fitted into a cylindrical electrostrictive element (not shown) and fixed. In the formation process, before the resin hardens, a tungsten (W) wire rod as a probe material and a metal 2 for leading out the electrode are inserted and hardened. The shape of the tip of the probe is formed by electrolytic polishing or mechanical polishing.Also, a metal coating is applied to the surface of the probe holder so that it does not connect with the probe material, and the surface of the probe holder is kept at ground potential.The inside of the cylindrical electrostrictive element is By using the electrode as a ground potential, it has an effect as a guard ring and can prevent the SZN ratio of the measurement signal from decreasing due to the drive signal of the actuator or external noise. Although polycarbonate was used as the resin material in this example, the present invention is not limited to this, and various materials such as ABS (acrylonitrile butadiene styrene copolymer resin), fluororesin, polypropylene, and methacrylic resin can be used. .

FIGS. 3(a) and 3(b) are schematic diagrams of an embodiment in which unevenness for fitting with a probe holder is provided also on the inside of the cylindrical electrostrictive element. FIG. 3(a) is a side sectional view, and FIG. 3(b) is a perspective view.

The concave part 7 provided on the probe holder 6 side and the convex part 8 provided on the cylindrical electrostrictive element 3 mesh to ensure firm fixation, and a spring mechanism with a notch 4 on the probe holder side facilitates attachment and detachment during replacement. It's easy. Vinyl chloride was used as the resin material of the holder 6, and the cylindrical electrostrictive element 3 was made of PZT: lead zirconate titanate (Pb(Zr4i)Os).

FIG. 4 shows a side view of a scanning tunneling microscope using the present invention. A probe 1 is attached to the tip of a cylindrical electrostrictive element 3. 9 is a sample to be measured. (A) is an enlarged view of the probe section. 10 is a Z-axis coarse movement micrometer, 11 is an I
-V amplifier, 12 is a Z-axis lock screw, 13 is a two-axis transverse micrometer, and 14 is a stack type vibration isolation table.

[Effects of the Invention] By using a resin material, it is possible to realize a probe holder that is extremely lightweight, can be connected by press-fitting, and can be attached and removed easily.

The moment of inertia of the STM actuator system is reduced, the resonant frequency is increased, and a scanning head suitable for high-speed scanning is realized.

A highly stable scanning tunneling microscope that uses a scanning head capable of high-speed scanning to shorten data acquisition time, reducing positional errors caused by thermal drift and decreases in resolution caused by surface deterioration due to changes in the sample over time. will be realized.

[Brief explanation of drawings]

FIGS. 1(a) to (d) are configuration explanatory diagrams of different embodiments of the present invention, FIG. 2 is a schematic diagram of a conventional probe holding mechanism, FIG. 3(a),
(b) is a side view and a perspective view of another embodiment of the present invention, and FIG. 4 is a side view of an STM using the present invention. 1: Probe, 2: Metal for electrode extraction, 3: Cylindrical electrostrictive element. Figure 2 Figure (0) (b) Figure 3

Claims (3)

[Claims] (1) A probe holder characterized in that a cylindrical holder body made of an insulating resin material that fits into a cylindrical electrostrictive element is provided with means for fixing the cylindrical electrostrictive element. (2) The fixing means consists of an axial notch provided in the cylindrical holder body, and by press-fitting the holder body into the cylindrical electrostrictive element, its elasticity allows the holder body to be inserted into the electrostrictive element. The probe holder according to claim 1, wherein the probe holder is configured to be fixedly held. (3) The fixing means comprises a convex portion provided on one of the holder main body and the cylindrical electrostrictive element, and a concave portion provided on the other side that fits into the convex portion. Probe holder according to claim 1 (4) The probe holder according to claim 1, characterized in that the surface of the holder body is coated with a conductive material, and the conductive material is grounded.