JPH04204206A - Length measuring standard method of scanning electromicroscope - Google Patents

Abstract

PURPOSE:To simply and accurately measure length by a non-standard method by providing a forcible vibration source such as a piezoelectric element and setting the amplitude or displacement of a part of an object to be measured or a part of a sample stage generated at this time to a reference length measuring dimension. CONSTITUTION:In such a state that the electron beam 9 of a scanning electromicroscope(SEM) is fixed constant, voltage is applied to the electrode 8 of a piezoelectric element 7 to minutely move a sample holder 5 and the displacement of an SEM image generated at this time is observed. By this method, especially, length of 0.1mum or less can be accurately and simply measured by a non-standard method.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a sample fine movement mechanism for a scanning electron microscope (SEM) and a standard length measurement method using the same.

[Conventional technology]

Figure 2 shows, for example, a sample stage for a scanning electron microscope (8EM).
sample stage % (5) of sample holder % (6
) is the sample to be measured attached to this sample holder, the head is a screw, and (9) is a scanning electron microscope* (SEM).
) shows the electron beam. v. The entire stage (4) can be freely moved within the electron microscope aS.

Figure 3 shows, for example, a scanning electron microscopy steel (SRM484ti) sold by the American company NBEI.
In the figure, (1) is the sample substrate plastic, (2) is the gold wire drawn on it, (
3) is a marker indicating the sample observation position.

Next, the operation will be explained. On the sample stage for a nine-scanning electron microscope (8KM) shown in Figure 2, the sample to be measured (6) attached to the sample holder (5) is (
After adjusting the position in two directions with the screw of the sample to be measured installed inside the sample stage of (4)
) is attached to the specimen stage of a scanning electron microscope (EIFM). At this time, the position adjustment in two directions is "c" for the electron beam of the scanning electron microscope (8KM) in (9).
m is performed to determine the reference position If of the measurement sample (6). Further, the entire sample stage (4) can be freely moved within the electron microscope.

Next, a standard length measurement method using this will be explained. Third
The SRM484a shown in the figure was examined using a scanning electron microscope (SKM).
) After mounting on the sample stage, first find the marker indicating the sample observation position in (3).

Next, the distance between the gold wires (2) is measured using a scanning electron microscope. For example, gold wire Line O and gold wire Line 1
The distance between gold wire LineO and gold@Line2 is 1μm, and the distance between gold wire LineO and gold@Line2 is 2μm. The distance between Line 2 and Gold @ Line 3 is 3 μm, and the distance between Gold sweep Line 3 and Gold fit Line 4 is 5 μm. ), or store it in a computer turf and use it as a length measurement standard.

[Problem to be solved by the invention]

The standard length measurement method using a conventional scanning electron microscope (BTrM) is carried out as described above, but (1) the positional relationship between the sample to be measured and the above-mentioned standard length measurement sample, especially minute errors in the Z direction; (2) Changes in date and time of set meal type electron microscope fl device, (3)
The calibration magnification must be checked for each magnification5.
(4) In order to obtain accurate values, the length measurement standard sample itself must be used, and the non-standard method has to be used for a long time. In the case of performing the measurement using the above-mentioned method, there are problems such as the need for periodic calibration using the length measurement standard sample itself, and (5) the lack of existing length measurement standard samples of 0.5 μm or less. It was developed to solve problem (5), and is a non-standard method, especially when 0.1
Scanning electron microscope that allows easy and accurate length measurements of micrometers or less
The purpose of this study is to obtain a standard length measurement method using a (SEM) wipe imitation@mechanism and this.

[Means to solve the problem]

A sample fine movement mechanism for scanning type microscopy (S, KM) and a method for pre-positioning a predetermined measurement using the same according to the present invention are provided in a sample stage for fixing an object to be measured. Alternatively, a forced vibration fp such as a piezo element is provided in contact with a portion of this sample stage.

[For production]

Scanning ff1i! in this invention! Zizhou Weikyo (8118M
) sample fine movement mechanism and length measurement standard sample using this, by providing a forced imaging source such as a piezo element.

By using the displacement S@ of a portion of the target object to be removed or a portion of the sample stage as the reference length measurement dimension, accurate length measurement can be easily performed using the non-standard method.

[True example]

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, (4) is the sample stage of a scanning electron microscope (SEM), (5) is the sample holder, (6) is the temporary measurement sample placed in this sample holder, and (7) is the interior of the sample stage. Five electrodes (8) are formed on the circumference and inside the piezo element. (
9) shows the electron beam of a scanning electron microscope (SEM). The entire stage of the sample stage (4) can be moved within the electron microscope.As shown in Figures 1-), a piezo element (7) is attached to the inside of the sample stage (4). is five electrodes (
8) is formed on the circumference and inside the piezo element.

In this case, one end of the piezo element is set as a fixed end, and the free end can be moved in the X7 direction by applying a voltage to each of the opposing electrodes x, Tx, y, and Te on the circumference. Also, inside! The free end can be moved in two directions by applying a voltage to the pole. Therefore, as shown in Fig. 1(a), by attaching this piezo element (7) inside the sample stage (4) and attaching the sample holder (5) and the sample to be measured (6) to it, ,
The sample to be measured can be moved in the X7Z directions.

If the piezo element shown here is used, an extremely small amount of f
i11 Constant sample movement becomes possible. Transferring piezo elements that are usually commercially available! E! lt is on the order of tens to hundreds of angstroms per -volt.

Now, the nine scanning electron microscopes configured in this way
When measuring a length of 0.5 μm or less using the sample stage sound of (19EM), the scanning electron microscope (S
While the electron beam (KM) remains fixed, the above voltage is applied to the piezo element to slightly move the sample holder (5), and the resulting displacement of the 81M image can be observed.

In addition, in the above example, the sample fine movement mechanism and the standard length measurement method using the same were shown using the sample stage of scanning electron microscope (s'Au) as an example. A sample stage such as a spectrometer (XPS), an auzi=-1 [audience spectrometer 1 (AFJ), a secondary ion mass spectrometer 41 (S Engineering M8), etc., may be used, and the same effects as in the above embodiments can be obtained. play.

〔Effect of the invention〕

As mentioned above, according to this discovery, scanning electron microscopy (E
By installing a forced imaging source such as a piezo element in the IEM, the amplitude and displacement of a part of the object to be measured or a part of the sample stage that occur at this time are set as the reference length measurement dimension. The positional relationship between the above-mentioned length measurement standard sample, especially in two directions, is small, and it is not affected by the date and time changes of the scanning electron microscope, and the calibration magnification must be checked for each multiplier. This non-standard method has the advantage of being able to easily and accurately measure lengths of 0.1 μm or less.

[Brief explanation of the drawing]

@Figure 1-) is a diagram showing a sample fine movement stage mechanism for a scanning electron microscope (SKM) according to an embodiment of the present invention, Figure 1 (b) is a diagram showing a piezo element, and Figure 2 is a diagram showing a conventional scanning type. Sample stage for electron microscope (SEM). FIG. 3 is a diagram showing a length measurement standard sample for a scanning electron microscope (Nichi-E!M). In the figure, (1) is the sample substrate plastic, (2) is the gold line drawn on it, and 13) is the observation position inside the sample +IIt.
(4) is a marker indicating scanning electron microscopy fi (BFi).
M) sample stage, (5) sample holder, (6) sample to be measured attached to this sample holder, (7)
is a piezo element added inside the sample stage, (9
) is the scanning electron microscope (SInM) electron beam, αQ
is a screw thread. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] In a scanning electron microscope (SEM) device, when measuring physical quantities such as the length and spacing of an object to be measured, it is used within the sample stage for fixing the object to be measured, or in contact with a part of this sample stage. A sample fine movement mechanism by providing a forced vibration source such as a piezo element, and the amplitude of a part of the object to be measured or a part of the sample stage that occurs at this time,
A standard length measurement method for a scanning electron microscope, characterized in that displacement is used as a reference length measurement dimension.