JPH03152448A - X-ray analyzer - Google Patents

Abstract

PURPOSE:To enable three-dimensional measurement of an external shape or an internal structure in a minute structure by providing a sample stage in a high vacuum chamber so that it can be displaced in the three-dimensional direction, by setting a sample thereon and by applying a fine-bundle electron beam to the sample. CONSTITUTION:A sample stage 2 which can be displaced in the three-dimensional direction is provided inside a high vacuum chamber 1 made of iron, for instance. A sample (e.g. LSI) S is set, as it is, on the upper surface of the stage 2. When an electron beam is emitted from an electron beam generating element 3, it is turned to be a fine-bundle electron beam SB by the operations of a condenser lens 4, and electron beam scanning element 5 and an objective lens 6 and applied to the sample S. A transmitted X-ray PX transmitted through the sample S, out of X-rays generated when the electron beam SB strikes on the samples S, falls on the detecting surface of an X-ray detector (e.g. a semiconductor X-ray detector, three units of which are provided below the stage 2 with appropriate spacing therefrom) 9. by displacing the stage 2 three-dimensionally on the occasion, the X-ray PX passes through each part of the sample S, and therefore the external shape or the internal structure of the sample S can be measured three-dimensionally.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an X-ray analysis device.

[Conventional technology]

For example, in order to three-dimensionally measure the external shape and internal structure of microdevices such as LSI, conventional methods
For example, a predetermined portion of a microdevice is cut out using a device such as a microtome to prepare a thin sample, and this thin sample is observed using a transmission or scanning electron microscope.

[Problem to be solved by the invention]

However, the above-mentioned conventional technology is a so-called destructive method in which the microdevice from which the thin sample was collected cannot be used again for its original purpose, and also requires some pretreatment, which requires time and effort to prepare the sample. It was something.

The present invention has been made with the above-mentioned considerations in mind, and its purpose is to improve the external shape and internal structure of microdevices such as LSI without destroying them or requiring troublesome pretreatment. An object of the present invention is to provide an X-ray analysis device that can three-dimensionally measure a structure.

[Means for solving the problem] In order to achieve the above-mentioned purpose, the following two means are adopted in this application.

The X-ray analysis device according to the first invention includes a sample stage disposed in a high-vacuum chamber so as to be freely displaceable in three dimensions, and a fine beam of electrons irradiated onto the sample placed on the sample stage. Among the X-rays generated at this time, the X-ray detector is characterized in that the X-rays that have passed through the sample are detected by an X-ray detector.

Furthermore, the X-ray analysis apparatus according to the second invention includes a sample stage disposed in a high vacuum chamber so as to be freely displaceable in three-dimensional directions, and a sample placed on the sample stage is The method is characterized in that an X-ray detector detects the X-rays that have passed through the sample among the X-rays generated when a fine-flux electron beam is irradiated and the fine-flux electron beam collides with the gI film target. There is.

[Function] In any of the above inventions, the X-rays that have passed through the sample are detected by the X-ray detector, so the sample can be observed non-destructively, and troublesome pretreatment is not required. .

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows the configuration of an X-ray analyzer according to the first invention of the present application. It's Nishide. Reference numeral 2 denotes a sample stage provided inside the chamber 1, on which a sample S such as an LSI is placed and held, and is movable in three dimensions by a drive operation mechanism (not shown), that is, vertically and horizontally. It is designed so that it can be moved, the sample mounting surface can be tilted, and it can also be rotated in each state.

Inside the chamber 1, in order from the top, there are an electron beam generating section 3 that is made of a filament or the like and emits an electron beam;
A condenser lens 4, an electron beam scanning section 5 for scanning the electron beam in the XY force direction, an objective lens 6, etc. are provided, and the electron beam emitted from the electron beam generating section 3 is reduced to a diameter of, for example, 1 μm by the members 4 to 6. The electron beam becomes the following fine flux electron beam 5B and is directed toward the sample S.

7 is a secondary electron detector provided on the side of the chamber 1, which detects the secondary electron beam emitted from the surface of the sample S by irradiating the surface of the sample S with the narrow electron beam SR, and generates a secondary electron image. This is what you get. 8 is a monitor for observing sample S.

The configuration up to this point is no different from a general scanning electron microscope.

9 is an X-ray detector, for example, a semiconductor It detects X-rays (hereinafter referred to as transmitted XvA) PX, and in the illustrated example, three units are installed at appropriate intervals below the inside of the chamber 1, more specifically below the sample stage 2 on which the sample S is placed. It is provided. These X-ray detectors 9 output signals representing the intensity of transmitted xgpx, and these signals are processed by a signal processing device not shown.

Therefore, the X-ray analyzer with the above configuration allows, for example, LS
When three-dimensionally measuring the external shape and internal structure of the fine structure of I, first, the LSI is placed on the upper surface of the sample stage 2 as a sample S without being made into a thin sample.

Next, when an electron beam is emitted from the electron beam generating section 3 in this state, this electron beam passes through the condenser lens 4 and the electron beam scanning section 5.
, by the function of the objective lens 6, etc., a predetermined finely focused electron beam S
B and irradiates the sample S.

Of the characteristic X-rays and continuous xfl generated when the narrow electron beam SB collides with the sample S, the transmitted X-rays Pχ that have passed through the sample S are incident on the detection surface of the X-ray detector 9. In this case, by changing the posture of the sample stage 2 and displacing it three-dimensionally, the transmitted X-rays PK pass through each part of the sample S. can be measured.

FIG. 2 schematically shows the configuration of an X-ray analyzer according to the second invention of the present application, and in this figure, the same symbols as those in FIG. 1 indicate the same or equivalent components.

In this figure, 10 is a thin film target provided near the input side of the fine beam electron beam SB of the sample S, and has a thickness of, for example, several micrometers.
m of Mo (molybdenum), Rh (rhodium), Cr
Made of metal such as (chrome).

In this embodiment, instead of directly irradiating the sample S with the fine flux electron beam SB from the electron beam generator 3, the sample S is irradiated with the thin II firing target 10, and the characteristic X generated at that time is
rays and continuous xgcx are irradiated onto the sample S, and among the characteristic X-rays and continuous xfIcx, the transmitted x that has passed through the sample S
f! px enters the detection surface of the X-ray detector 9.

In this embodiment as well, the external shape and internal structure of the fine structure of the sample S can be measured three-dimensionally as in the above-mentioned embodiments.

In each of the embodiments described above, the scanning electron microscope includes an X-ray detector 9.
However, the transmission electron microscope may be provided with an X-ray detector 9. It is not necessarily necessary to provide a plurality of X-ray detectors 9; only one X-ray detector 9 may be provided; furthermore, in that case, the position of the detector 9 may be movable.

Furthermore, in the embodiment shown in FIG. 2, a scintillation counter can also be used as the X-ray detector 9.

〔Effect of the invention〕

As explained above, in the present invention, the X-ray detector detects the transmitted X-rays that have passed through the sample, so the external shape and internal structure of the sample can be measured three-dimensionally. can do. According to the present invention, it is possible to carry out predetermined measurements without destroying the sample and without any troublesome pre-treatment. useful for measuring

[Brief explanation of the drawing]

FIG. 1 is a diagram schematically showing the configuration of an X-ray analyzer according to the first invention of the present application, and FIG. 2 is a diagram schematically showing the configuration of the X-ray analyzer according to the second invention of the present application. be. 1...Chamber, 2...Sample stage, 9...
X-ray detector, 10... thin film target, S... sample, SR... narrow electron beam, PX... X transmitted through the sample
line. Figure 2

Claims (2)

[Claims] (1) A sample stage is installed in a high vacuum chamber so that it can be moved in three dimensions, and the sample placed on the sample stage is irradiated with a fine beam of electrons.
An X-ray analysis apparatus characterized in that, of the X-rays, X-rays that have passed through the sample are detected by an X-ray detector. (2) A sample stage is installed in a high-vacuum chamber so that it can be freely displaced in three dimensions, and the sample placed on the sample stage is irradiated with a fine beam of electrons through a thin film target. An X-ray analysis apparatus characterized in that, of the X-rays generated when an electron beam collides with the thin film target, X-rays that have passed through the sample are detected by an X-ray detector.