JPH04112440A - Observation device - Google Patents

Abstract

PURPOSE:To observe the intra-hole side face without dividing material to be analyzed, by furnishing a needle probe of neg. voltage on the extension line of an electron beam, curving the electron beam, and bombarding with the side face of the material. CONSTITUTION:A needle probe 8 movable vertically is installed below the center of a material fitting part 6 of a scanning electron microscope. When a neg. voltage of approx. -5kv is impressed on this needle probe 8 and an electron gun 1 is given an electron acceleration voltage of 1-4kv, an electron beam A emitted from the electron gun 1 advances being bent by the neg. voltage of the needle probe 8 and bombards with the inner side face of a hole (b). When the electron beam A bombards with the inner side face of the hole (b), secondary electrons B are emitted from the bombarded part and seized by a secondary electron sensor 7 which is kept at a pos. potential. Accordingly the inner side face of the hole (b) is displayed as an image by varying the bombardment position of electron beam A one after another and subjecting the result from seizure of secondary electrons B at the time to an analytical processing, and thus their observation is made practicable.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an electron microscope type observation device.

[Prior art and problems to be solved by the invention] A scanning electron microscope is a device that irradiates the surface of an analysis material with an electron beam and detects the emitted secondary electrons. The detected value of electrons changes, and this amount of change is analyzed using a computer and displayed as an image.

By the way, as shown in Figure 2 (a), the analysis target is substrate a.
Since it was impossible to observe the inner surface of a hole drilled in the hole using a conventional electron microscope,
As shown in Figure (1)), the substrate a of the analysis material piece was divided and the inner surface of the hole was observed.

However, it is complicated to cut the substrate a to form analysis materials, and furthermore, the cutting process may deform the inner surface of the hole that is the object of observation, so accurate observation is not always possible. There are problems with this.

Therefore, the present invention proposes an observation device that allows observation of the inner surface of a hole without dividing the analysis sample piece.

[Means to solve the problem]

The observation device according to the present invention scans and irradiates the surface of an analysis material with an electron beam, detects secondary electrons emitted from the irradiated surface, analyzes the surface state of the analysis material, and displays an image using scanning electron beams. In a microscope-type observation device, a needle probe to which a negative high voltage is applied is installed on the electron beam extension line, and the electron beam is bent and irradiated onto the side of the analysis material to display an image of the side of the analysis material. That is.

[Effect]

When the analysis sample piece is positioned so that the electron beam is incident on the inner surface of the hole, which is the object of observation, and an appropriate negative voltage is applied to the needle probe, the electron beam bends and travels, colliding with the inner surface of the hole. Therefore, if the electron beam is scanned in a circular manner, it will collide with the entire circumference of the inner surface of the hole, and further, by adjusting the vertical position of the needle probe or adjusting the voltage, the collision point of the electron beam will shift in the vertical direction of the inner surface of the hole. By detecting secondary electron emission upon electron beam collision and performing analysis processing, it becomes possible to display an image of the inner surface of the hole.

〔Example〕

Next, examples of the present invention will be described.

The apparatus of the present invention is basically the same as a scanning electron microscope, and as shown in FIG.
2. It includes an electron gun 1 consisting of an anode 13, a converging lens (coil) 2, an objective aperture 3, a scanning coil 4, an objective lens (coil) 5, a material mounting section 6, and a secondary electron detector 7. Furthermore, a needle probe 8 that can be moved vertically is installed below the center of the material mounting section 6, and the operation of the scanning coil 4, the operation of the needle probe 8, and the detected value of the secondary electron detector 7 are used as processing inputs. , a display section (not shown) that performs analysis processing and displays images.

When observing the inner surface of a hole in an analysis sample piece made by drilling a hole in a substrate a as shown in FIG. 2(a), the electron beam A from the electron gun An analysis material piece is attached to the material mounting part 6 so that the analysis material enters the hole, and an electron beam A is emitted from the electron gun 1 to observe the inner surface of the hole. That is, a negative voltage of about 15 kV is applied to the needle probe 8, and the electron gun 1 is
Assuming that the electron acceleration voltage of is 1 to 4 kV (voltage required for the electron beam to bend in a predetermined manner as described later), the electron beam A fired from the electron gun 1 is bent by the negative voltage of the needle probe 8. It advances and collides with the inner surface of the hole. If the electron acceleration voltage of the electron gun 1 is low, the electron beam A will bend before entering the hole, and if it is high, it will overcome the negative voltage of the needle probe 8 and pass through the hole. Therefore, adjust it appropriately. When the electron beam A collides with the inner surface of the hole, secondary electrons B are emitted from the colliding portion, and the secondary electrons B are captured by the secondary electron detector 7 which maintains a positive potential.

Therefore, by sequentially changing the collision position of the electron beam A and analyzing the capture of the secondary electrons B at that time, it is possible to display an image of the inner surface of the hole and observe it.

The collision position of the electron beam A can be adjusted by moving the electron beam A scanning needle probe 8 up and down, but it is also possible to adjust the electron acceleration voltage of the electron gun 1, adjust the negative voltage of the needle probe 8, and adjust the material mounting part. This can also be achieved by adjusting the position of step 6.

〔Effect of the invention〕

As described above, the present invention is a conventional scanning electron microscope type observation device in which a needle probe with a negative voltage is provided on the extension of the electron beam, so that the electron beam is bent and collided with the side of the analysis sample. This makes it possible to observe the inside surface of the hole without dividing the analysis material.

[Brief explanation of the drawing]

Fig. 1 shows the principle of the device of the present invention, Fig. 2 shows analysis data pieces, (a) before division, (b) after division, and Fig. 3 a cross section of the main part of the embodiment of the inventive device. It is a diagram. 1-Electron gun 11-Filament 12-Wehnelt 13-Anode 2-Converging lens 3-
=Objective aperture 4-Scanning coil 5-Objective lens 6-=Data mounting section 7-Secondary electron detector 8-Needle probe 1 Fig. 2

Claims (1)

[Claims] (1) Scanning and irradiating the surface of the analysis material with an electron beam,
In a scanning electron microscope type observation device that detects secondary electrons emitted from the irradiated surface, analyzes the surface condition of the analysis sample, and displays an image, a needle probe with a high negative voltage applied to the extension line of the electron beam is used. An observation device that displays an image of the side surface of the analysis material by bending an electron beam and irradiating the side surface of the analysis material.