JPS5835853A - Image display unit - Google Patents

Abstract

PURPOSE:To obtain an image display unit capable of displaying an X-ray plane analysis image clearly as well as a secondary electron image by establishing lens current settings of a focus lens individually for taking pictures of the secondary electron image and the X-ray plane analysis image and by providing a mechanism to switch them. CONSTITUTION:In a focus driving circuit 7, the current If flowing into a focus lens 3 is set so that the diameter of an electron beam radiated on a phosphor screen 5 is made minimum the same as before, and the lens current is also set so that a proper beam diameter is available for an X-ray plane analysis image. Said current If and the lens current can be switched by means of a transfer section 8, and when the transfer section 8 is switched said current If or the lens current flows through the focus lens 3. Accordingly, when the transfer section 8 is switched from the secondary electron image for taking a picture of the X-ray plane analysis image, the X-ray distributed image of luminescent spots with a proper size can be available and the photographed data become easy to observe.

Description

[Detailed description of the invention] The present invention relates to an image display device for a scanning electron microscope.

In general, an image display device of a scanning electron microscope is constructed such that an electron beam 2 emitted from a cathode 1 is focused by a focusing lens 3, deflected by an XYIJn direction coil 4, and hits a fluorescent surface 5, as shown in FIG. It has become.

Image display devices for photography of scanning electron microscopes that take secondary electron images, reflected electron images, transmission electron images, etc., are desired to have a high resolution, so the image display device shown in Fig. 1 As shown in FIG. 2, the focusing lens 3 is set by the focus drive circuit 6 so that the diameter of the sterling beam hitting the fluorescent surface 5 is minimized.

However, when a CRT set in this way is used to display an X-ray plane analysis image showing the distribution of a specific element in a sample,
One bright spot on the CRT surface corresponding to one count of X-rays becomes very small, and if you take a photograph of the XWs surface analysis image in this state, the size of each bright spot is so small that it is extremely difficult to see the Xd.
It ended up being a surface analysis photo.

An object of the present invention is to provide an image display device that can clearly display not only secondary electron images but also X-ray plane analysis images.

In order to achieve such an object, the present invention sets the lens acid flow setting point of the focusing lens independently for the secondary electron image and the X-ray plane analysis image, and provides a mechanism for switching between the two. It is something.

FIG. 2 is a block diagram showing one embodiment of an image display device according to the present invention. In this figure, the same reference numerals as in FIG. 1 indicate the same things. The configuration that differs from that in FIG. 1 is in the focus drive circuit 7, which controls the current value If flowing to the focusing lens 3 so that the diameter of the adult beam irradiated onto the fluorescent surface 5 is minimized as in the conventional case. is set, and a lens current value that provides an appropriate beam diameter in the Xa-plane idol is also set. The current value (2) and the lens current value can be switched by a switching unit 8, and by switching the switching unit 8, a current or a lens current value based on the above-mentioned Kame flow value flows through the focusing lens 3. It has become.

In this way, by switching the switching unit 8 when taking an X-ray plane analysis image from the secondary Seiko image, it is possible to obtain an XfIs distribution image with bright spots appropriately thickened to 4K, and the photographic data can be easily viewed.

FIG. 3 is a block diagram showing another embodiment of the image display device according to the present invention. A scanning mode switching section 9 is attached to the switching section 8 . The scanning mode switching unit 9 has the ability to select the scanning method and the type of signal image to be displayed on the CRT, and is switched by the signal from the scanning mode switching unit 9. If the focus of the CRT is switched when the section 7 is switched, the switching section 8 can be automatically switched, which has the advantage of eliminating the need for complicated operations.

As is clear from the above, the image display device according to the present invention can clearly display not only secondary electron images but also X-ray analysis images.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a conventional image display device, FIG. 2 is a block diagram showing an embodiment of the image display device according to the present invention, and FIG. 3 is a block diagram showing another embodiment of the image display device according to the present invention. FIG. ■... Cathode, 2... Seiko beam, 3... Focusing lens, 4... Deflection coil, 5... Fluorescent surface, 6, 7...
・Focus vJ1 figure 2

Claims (1)

[Claims] 1. In a scanning electron microscope that displays a secondary Seiko image and an X-ray surface analysis image on a CRTK, the focus conditions of the CRT's electron beam can be switched between when displaying a secondary Seiko image and when displaying an X-ray surface analysis image. An image display device characterized in that the diameter of an electron beam focused on a fluorescent surface is switched.