JPS6136912Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a thin film sample preparation apparatus for preparing thin film samples of high melting point metals, metal oxides, nitrides, etc. using ion bombardment, that is, sputtering phenomenon.

For example, samples for transmission electron microscopy are made of materials,
Although it varies depending on conditions such as the accelerating voltage of the microscope, it generally requires a thin film of several thousand angstroms or less. Processing of such thin films is carried out using ion bombardment, or sputtering phenomenon, but conventionally, ion beam irradiation is stopped every 30 minutes, and optical measurements are taken to determine whether microscopic holes have been formed in the sample. The machining process was stopped when a hole was formed. However, with this method, the sample must be constantly monitored during processing, and the ion beam irradiation must be stopped from time to time to observe the sample, which is a hassle, and processing takes a long time. . There was also a risk that the spattered substances would adhere to the optical detection section, the light source, etc. and obstruct visibility.

The present invention was proposed to solve these conventional problems, and its purpose is to automatically and efficiently process a desired thin film without constantly monitoring the sample. The purpose of the present invention is to provide a thin film sample preparation device that can perform the following steps.

Hereinafter, details of the present invention will be explained based on an embodiment shown in the drawings. In the figure, reference numeral 1 denotes a cylindrical vacuum container made of glass or the like, and inside the vacuum container 1 there is an ion source section 4 consisting of an anode 2 and a cathode 3, a holder 5 for holding a sample, a beam detector 6,
A beam stopper 7 and the like are arranged. A small amount of inert gas (Ne, Ar, Kr, Xe, etc.) is introduced into the anode 2 from the outside of the reduced pressure container 1 through a pipe 8 and a valve 9. ionized between The ion beam formed between the anode 2 and the cathode 3 is irradiated onto the sample held by the holder 5. The holder 5 is provided with a goniometer whose angle can be adjusted in the range of 0 to 90 degrees, thereby making it possible to adjust the irradiation angle of the ion beam to the sample. The beam stopper 7 is made of a magnetic material, has a through hole 7a in the center through which the ion beam from the ion source section 4 passes, and is disposed between the ion source section 4 and the holder 5. The beam stopper 7 is movable in a direction perpendicular to the ion beam, and can block the ion beam by moving in the same direction.
The holding body 5 is surrounded by a liquid nitrogen cooling shield 10, and a motor 1 is installed inside this shield 10.
1 is provided. The holder 5 is rotated by the motor 11 while maintaining a selected constant angle with respect to the ion beam. The beam detector 6 is located behind the holder 5, and when the ion beam passes through the sample held by the holder 5,
The transmitted ion beam is detected and a detection signal is output to a determiner 12 provided outside the reduced pressure container 1. The determination device 12 includes a power source 13
Together with the electromagnet 14 disposed inside the reduced pressure container 1, it constitutes a stopper driving means 15. This determiner 12 is energized by a detection signal from the beam detector 6, and activates the power source 13. The power source 13 drives an electromagnet 14, and the electromagnet 14 attracts the beam stopper 7. No, the determination device 12 can adjust its operating level.

With the above configuration, when the valve 9 is opened and a small amount of inert gas is supplied to the ion source section 4 through the pipe 8, an ion beam is formed between the anode 2 and the cathode 3 in the ion source section 4 and is accelerated. The ion beam passes through the through hole 7a of the beam stopper 7 and is irradiated onto the sample held by the holder 5. Then, the sample is processed into a thin film by ion bombardment, and when it becomes thin enough for the ion beam to pass through, the ion beam that has passed through the sample is detected by the beam detector 6. The detection signal from the detector 6 is output to the determiner 12, energizes the determiner 12, and activates the power source 13. This drives the electromagnet 14 and attracts the beam stopper 7, so that the through hole 7a of the stopper 7 moves and the ion beam from the ion source section 4 is blocked by the beam stopper 7, completing the thin film processing.

Therefore, this thin film sample preparation device automatically stops when processing is completed, so there is no need to constantly monitor the sample as in the conventional method, and the ion beam irradiation can be stopped during processing. There is no need to monitor the machining status of the machine, so machining can be done in a short time. Furthermore, since the conventional method of optically observing the machining state is not adopted, problems such as spattered substances adhering to the optical detection unit, light source, etc. and obstructing visibility do not occur.

Further, in particular, in the embodiment, the ion beam irradiation is performed while the sample is being rotated by the motor 11, so that the entire surface of the sample can be processed uniformly. Furthermore, by processing the sample within the liquid nitrogen cooling shield 10, contamination of the sample can be prevented. Furthermore, if the operating level of the determiner 12 can be adjusted as appropriate, a thin film with a desired thickness can be obtained. Furthermore, a machining completion display means operated by the output from the detector 6 may be provided.

As detailed above, according to the present invention, a desired thin film can be automatically formed without constantly monitoring the sample.
Moreover, it is possible to provide a thin film sample preparation device that can efficiently process a thin film sample.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of the same embodiment. 4... Ion source section, 5... Holder, 6... Beam detector, 7... Beam stopper, 10... Liquid nitrogen cooling shield, 11... Motor, 12... Judgment device, 13... Power supply, 14 ...Electromagnet, 15...
Stopper driving means.

Claims (1)

[Claims for Utility Model Registration] (1) A vacuum container, a holder placed in the vacuum container to hold a sample, and a holder placed in the vacuum container to ionize an inert gas between an anode and a cathode. an ion source unit that forms an ion beam by irradiating the sample held on the holder to thin the sample by sputtering; and a beam detector that detects the ion beam that has passed through the sample. a beam stopper that is selectively inserted between the ion source section and the holder to block the ion beam; and a beam stopper that is selectively inserted between the ion source section and the holder to block the ion beam; A thin film sample preparation apparatus comprising: a beam stopper driving means interposed between the holder and the holder. (2) The beam stopper driving means includes a determiner that sends out an output when the output of the beam detector exceeds the predetermined value, and an output of the determiner that is connected to a power source to beam stop the beam stopper using electromagnetic force. A thin film sample preparation apparatus according to claim 1, characterized in that the thin film sample preparation apparatus is comprised of an electromagnet for moving the sample to a certain position. (3) The thin film sample preparation apparatus according to claim 1, wherein the determination device is capable of varying the determination level. (4) The thin film sample preparation apparatus according to claim 1, wherein the holder is adjustable in angle with respect to the ion beam. (5) The thin film sample preparation apparatus according to claim 1, wherein the holding body is rotationally driven by a motor.