JPS6150061A - Ultrasonic microscope - Google Patents

Abstract

PURPOSE:To take out a lead without hampering the movement of a sample base, by retaining a liquid metal between a terminal plate of the sample based held with a static air bearing and probes provided on a support plate to make an electrical connection. CONSTITUTION:The surface of a sample base 16 is covered with an insulator 19, on which terminals 20 are arranged. Probes 21 mounted on a support plate 22 is mounted on a guide 14 at the position facing the respective terminals 20 and the tip of the probes 21 form a concave with the V-shaped cross-section. The tip of the probes 21 is held with a fine gap from the top of the terminal 20 and a liquid metal 23 is inserted therebetween to make an electrical connection.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention is based on mechanical scanning of a sample! The present invention relates to an ultrasonic microscope that performs fjt imaging.

[Background of the invention]

In recent years, it has become possible to detect the generation of ultrasonic sound waves with ultrasonic frequencies up to IGHz, so it has become possible to realize sound wavelengths of about 1 μm underwater, and as a result, a high-resolution sonic imaging device can be obtained. -116058, etc. That is, a concave lens is used to create a focused sound wave beam, achieving a high resolution of 1 μm.

By placing a sample in the beam and detecting the ultrasonic waves reflected by the sample, we can elucidate the elastic properties of minute regions of the sample.
Alternatively, if the sample is mechanically scanned in two dimensions and the intensity of this signal is displayed as a brightness signal on a cathode ray tube, it is possible to magnify the minute pain structures in the sample.

FIG. 1 is a diagram showing the main components of the ultrasound microscope. The focusing, transmission and reception of ultrasonic waves is performed by a spherical lens 1, and its structure consists of optically polishing one side of a material made of cylindrical fused silica, etc., and then placing a piezoelectric thin film (ZnO) 2 on top of it.
A pulse 5 generated from a pulse oscillator 4 is applied to the piezoelectric thin film 2 having a sandwich structure, which is sandwiched between the upper and lower electrodes 3, to generate an ultrasonic wave 6.

In addition, a concave hemispherical hole with a diameter of about 0.1 mmφ to 1.0 mmφ is formed at the other end, and between this hemispherical hole and the sample, there is a hole for propagating the ultrasonic wave 6 to the sample 7. medium (eg water) 8 is filled.

Ultrasonic waves 6 generated by the piezoelectric thin film 2 propagate in the cylinder as plane waves. When this plane wave reaches the hemispherical hole, quartz (sound speed 6000 m/s) and water (sound speed 1500 m/s)
A refraction effect occurs due to the difference in the speed of sound between the sample 7 and the sample 7, and the focused ultrasonic waves 6 can be irradiated onto the surface of the sample 7. On the contrary, the ultrasonic waves coming from the sample 7 are collected and phased by the spherical lens, become plane waves, and reach the piezoelectric thin film 2, where the RF signal 9
is converted to This RF signal 9 is received by a receiver 10,
Here, it is detected by diode and converted into video signal 11, and C
It is used as an input signal for the RT display 12.

In the apparatus configured in this manner, when the sample 7 is two-dimensionally scanned within the x-y plane by the sample stage drive power supply 13, the intensity of reflection from the sample surface as the sample scans changes two-dimensionally from the CRT surface. Shown 2 on page 1.

The faster the scanning speed for sample F) 7, the shorter the time it takes to form one screen, which leads to improved operability. Because of this, the scanning speed is also lower than the
, the y-axis scan takes about 10 seconds.

As described above, on the sample being scanned in the x-y plane.

In a device that irradiates ultrasonic waves and displays images using the ultrasonic waves reflected from a sample, if there is a change in elastic properties near or inside the sample, the reflected ultrasonic waves will have different amplitudes and A change in phase occurs. Since this phase is sensitively affected by the distance between the spherical lens and the sample, the scanning sample surface and the focal plane of the ultrasonic beam must be configured so that they are always kept in the same spatial phase condition. Accuracy is a problem when scanning a sample, and the use of a hydrostatic air bearing is being considered as a sample moving table suitable for such an apparatus. The feature of this static pressure air bearing is that the sample stand is supported by the static pressure of the air supplied between the bearing and the sample stand, so the frictional resistance of the bearing is small.
There is no wear and tear.

Furthermore, it moves smoothly without being affected by slight irregularities on the sample stage and bearing surface.

Figures 2 (a) and (b) show the configuration of a sample moving table using the above-mentioned static pressure air bearing, and Figure 2 (b) shows the structure of the sample moving stage using the above-mentioned static pressure air bearing.
It is a sectional view of figure (a). In the figure, 14 is a guide portion. A compressed air outlet 15 is attached to the guide portion at a predetermined position, and the sample stage 16 is held by the compressed air discharged from the compressed air outlet 15. 17 is a compressed air intake port. Further, 18 is a drive shaft of the sample stage 16.

By using a sample stage with tIW as described above, the vertical movement of the sample during scanning can be kept to 0.03 μm or less, and it can operate extremely stably as a sample stage for ultrasonic microscopes and the like.

When observing a sample with the above-mentioned ultrasonic microscope, there are demands to accurately measure the temperature of the sample during observation, and to heat the sample with a heater provided near the sample. There is also a demand to operate IC devices and observe how the temperature of each part changes.

In order to satisfy these requirements, it is necessary to provide a large number of lead wires from the periphery of the sample.

However, taking out a large number of lead wires from the sample stage, which uses a static pressure air bearing and is characterized by stable scanning without sliding, results in problems with the movement of the sample stage due to the rigidity of the lead wires. becomes.

[Purpose of the invention]

The present invention is intended to resolve such problems and proposes an ultrasonic microscope that does not interfere with the movement of the sample stage.

[Summary of the invention]

A feature of the present invention is that liquid gold a
(e.g. mercury) to make the electrical connection.

[Embodiments of the invention]

Embodiments of the present invention will be described below based on FIG.

The surface of the sample stage 16 is covered with an insulator 19, and a plurality of terminals 20 are arranged on the upper surface. The upper surface of each terminal 20 is finished to be the same plane.

Further, contacts 21 attached to a support plate 22 are attached from the guide portion 14 at positions facing the terminals 20, respectively. The tip of the contactor 21 has a concave surface with a V-shaped cross section.

A slight gap is maintained between the tip of the contactor 21 and the upper surface of the terminal 20, and a liquid metal layer 2 is kept between them.
3 to enable electrical connection.

If the shape of the terminal 20 is made larger than the scanning range of the sample stage 16, even during scanning, the contact 21 can be moved from the terminal 20.
It does not come off and can operate stably.

Although this is omitted in the diagram, a piezoelectric element such as PZT is placed on the sample stage, and stress can be applied to the sample by utilizing the expansion and contraction caused by applying voltage to the piezoelectric element. can also be easily achieved.

Furthermore, when the sample 25 is mounted on a sample stand with such a configuration, if the sample 25 and the terminal 20 are connected with the lead wire 26, information can be transmitted to the outside of the sample stand via the lead LA24. can.

〔Effect of the invention〕

As mentioned above, although the present invention has a simple configuration.

It has the feature that electrical connections can be made to terminals provided on the sample stand without any hindrance to the movement of the sample stand, which is supported in a non-contact manner by hydrostatic air bearings or the like.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an ultrasonic microscope, FIG. 2 is a diagram showing the main configuration of a hydrostatic bearing, and FIG. 3 is a diagram showing an embodiment of the present invention. fJ 1 mouth'fJ 2 mouth (ku)

Claims (1)

[Claims] 1. A means for irradiating a sample with an ultrasonic beam of a predetermined focus through a liquid medium and detecting a turbulent sound wave from the sample, a sample stage for holding the sample, and mechanical scanning of the sample stage. In an ultrasonic microscope that has a scanning means and images the sample by changing the amplitude or phase of the disturbed sound waves accompanying mechanical scanning, the sample stage is held without sliding by a hydrostatic air bearing. It is also equipped with a terminal board for electrical connection from the outside, and the fixed part has the above-mentioned first part.
a contactor facing the terminal of the terminal plate, a liquid metal is held between the terminal and the contactor, and an electrical connection is made from the outside to the sample stage via the liquid metal. An ultrasonic microscope featuring: