JPH02214046A - Electron beam recording and reproducing device - Google Patents

Abstract

PURPOSE:To miniaturize a device by forming each compact electronic optical system as the one of small angle deflection by arranging the electronic optical system in two-dimensional manner on a recording medium. CONSTITUTION:The recording medium 4 is irradiated with an electron beam 2 emitted from an electron gun 1 with plural lenses 3, and the electron beam 2 scans the medium 4 with a deflector 5. Also, a signal 6 generated when the medium 4 is irradiated with the electron beam 2 is detected with a detector 7. (n) electronic optical systems 10-120 in which (m) electronic optical systems are arranged in line are arranged in the circumferential direction of the medium 4. By forming the device in such a constitution, a distance D between the electronic optical systems in a radius direction is expressed as D=(R2-R1)/m=10 mm, and it is enough to constitute the electronic optical system 10, and also, it is sufficient to set a deflection quantity (r)(=D/2n) from the optical axis of each electronic optical system at 0.5mm, which reduces the deflection range of the electron beam, and the miniaturization of the device is attained.

Description

[Detailed description of the invention]

[Industrial Application Field 1] The present invention relates to a high-density recording and reproducing device using an electron beam,
In particular, the present invention relates to an electro-optical device suitable for miniaturization. 2. Description of the Related Art Since electron beams can be narrowed easily, extremely high density recording and reproducing devices can be achieved by using electron beams. From this point of view, a recording and reproducing apparatus (see FIG. 3) as described in Japanese Patent Application Laid-Open No. 59-221846 has already been devised.

[Problem to be solved by the invention]

However, when the electron optical system of the present invention is applied to a recording/reproducing device, it is necessary to make the distance between the deflector and the recording medium sufficiently long due to deflection aberration. For this reason, the electron optical system has the disadvantage of being extremely large, and the aberrations of the lenses and deflectors make it impossible to achieve high density. The present invention solves the above problems and provides an electro-optical device that is extremely suitable for miniaturization.

[Means to solve the problem]

A deflector is required to deflect the electron beam, and when a deflector is used, it is inevitable that deflection aberration will occur. in general,
In order to reduce deflection aberration, it is sufficient to increase the size of the deflector, which is the opposite of the case with lenses. Therefore, it is generally difficult to deflect an electron beam to a large angle with a small electron optical system. Therefore, in the present invention, a plurality of electron optical systems are arranged two-dimensionally, and each optical system is deflected by a small angle to achieve miniaturization.

[Effect 1] It has already been mentioned that the electron optical system can be made smaller by making the deflection of the electron beam smaller. In this case, since the scanning range of the electron beam is limited to a small area, it is not possible to scan the entire surface of the recording medium. Therefore, it becomes possible to use a plurality of small optical systems. On the other hand, since the above-mentioned recording medium is rotated in a disk shape as shown in Fig. 3, by arranging the above-mentioned small optical systems in a line in the radial direction and deflecting the electron beam only in this radial direction, the entire surface of the recording medium can be covered. It will be possible to scan. However, in this case, the deflection range of the electron beam needs to be approximately the distance between the optical systems, which is also difficult when considering implementation. Therefore, in the present invention, this compact optical system is arranged two-dimensionally as shown in FIG. As a result, the optical system can be easily arranged, and the entire surface of the recording medium can be scanned even if the deflection range of the electron beam is reduced. [Embodiment] An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1(a) and FIG. 1(b) are cross-sectional views taken perpendicular to each other. The electron beam 2 emitted from the electron gun 1 is passed through several lenses (
(Here, for simplicity, only one piece is shown.) 3 indicates the recording medium 4.
is irradiated. At this time, the electron beam 2 is scanned over the medium 4 by the deflector 5. Further, a signal (for example, secondary electrons or reflected electrons) 6 that is generated when the electron beam 2 irradiates the medium 4 is detected by a detector 7. Further, a plunker 8 for turning on and off irradiation of the sample with the electron beam 2 is also arranged. As shown in FIG. 1, m pieces of such electron optical systems are arranged in a row to form an electron optical system 10, and as shown in FIG. n pieces are arranged in the circumferential direction. Note that the n electron optical arrays are arranged so that the optical axes of the respective electron optical systems do not overlap on the same circumference and are slightly shifted from each other. It is a disc-shaped recording medium 4 that rotates around the center and records in a radius range from R1 to R2. In one embodiment of the invention, R1=30mm, R2=150mm, n=12,
m=12, that is, the total number mn=144 electron optical systems were arranged as shown in FIG. At this time, the distance between the electron optical systems in the radial direction is n = (R2-R1)/m = 10 mm
The electron optical system 10 may be configured with
It is sufficient if there is. Since the amount of deflection is small in this way, the deflection aberration is very small, making it easy to focus the electron beam narrowly, making extremely high-density recording possible. Here, in order to maintain the distance between the electron optical systems at 10 mm, the radial electron optical systems (12 in this embodiment) are integrated. In order to easily realize this integration, the electron gun 1 is a semiconductor electron gun that extracts electrons from a PN junction of a semiconductor, the lens 3 is an electrostatic type, and the deflector 5 is an electrostatic type.
uses a magnetic field type. With such an optical system, the electron beam was focused to 0.1 μm at an accelerating voltage of 5 kV, and a high recording density of 109 bits/cm 2 was achieved. In this embodiment, the electron optical systems are integrated in each radial direction, but it goes without saying that the system is not limited to this.In short, multiple electron optical systems are arranged with precision as in the embodiment shown in Fig. 3. All you have to do is do it. Further, the electron optical system is not limited to that of this embodiment. For example, it goes without saying that a field emission type or a thermionic electron gun may be used for the electron gun, and either an electrostatic type or a magnetic field type may be used for the lens 3 and the deflector 5. It is clear that the present invention can be practiced without limiting the number of objects to this embodiment. (Effect of the Invention 1) According to the present invention, the deflection range of the electron beam can be reduced, so that an extremely compact electron beam recording and reproducing apparatus can be realized.

[Brief explanation of the drawing]

FIG. 1(a) is a cross-sectional view of an electron optical system according to an embodiment of the present invention. The same figure (b) is a vertical cross-sectional view of the above-mentioned electron optical system.
The figure is a plan view showing the arrangement of each electron optical system in the electron beam recording/reproducing apparatus of the present invention. FIG. 3 is a schematic longitudinal sectional view showing a conventional electron beam recording/reproducing apparatus. Explanation of symbols 1.301: Electron gun, 2,302: Electron beam, 3.303
: Lens, 4,304: Recording medium, 5,305: Deflector, 6: Signal (e.g. secondary electrons or reflected electrons), 7,30
7: Detector, 8 niblanker 9 near node, 10.20
．． 30. ...12o: Electron optical system, 11.
12.13.14: Electron optical system. Figure 162 3rd garden

Claims (1)

[Scope of Claims] 1. Lens means for irradiating a recording medium with an electron beam emitted from an electron gun, a deflection means for scanning the electron beam on the recording medium, and a lens means for irradiating the recording medium with the electron beam; It is characterized in that an electron optical system is two-dimensionally arranged, which includes a detection means for detecting a signal generated when irradiating the recording medium, and a blanking means for turning on and off the irradiation of the electron beam on the recording medium. Electron beam recording and reproducing equipment. 2. The above recording medium is on a disk and rotates around the center of the disk, and a plurality of electron optical systems are arranged radially, and the distances between the radial center and each electron optical system are all different. An electron beam recording and reproducing apparatus according to claim 1, characterized in that: 3. In the above electron optical system, the electron gun is a semiconductor, the lens is an electrostatic type, and the deflector is a magnetic field type. electron beam recording and reproducing equipment.