JPS63200451A - Linear electron beam device - Google Patents

Abstract

PURPOSE:To improve yield in large area heat treatment by making an aperture width of a mask smaller than a maximum deflection width with which stable beams with very little aberration or the like can be obtained, and next by aligning a sample on a position where electron beams passing through the mask aperture part are radiated, and thereafter by scanning linear electron beams more largely than the mask aperture width. CONSTITUTION:Linear electron beams 4 emitted from an electron gun, which is composed of a linear cathode 1, a Wehnelt electrode 2, and an anode 3 in a vacuum container 14, are focused as linear electron beams on a sample 9 by a lens 5. The focused linear electron beams are scanned on the sample 9 by a deflector 6 and interrupted by a mask 8 and so they pass through only a mask aperture 7 part. Heat treatment is thus performed by electron beams on the sample 9 only in a radiation region of the electron beams which pass through the mask aperture 7. After heat treatment is performed once, the sample 9 is moved so that the range of the sample 9, where heat treatment is next required, come within the region of electron beam radiation and again electron beams are radiated and scanned there. When these procedures are repeated, heat treatment can be performed uniformly in the region where heat treatment is required for the sample surface.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a linear electron beam device.

(Prior art) Conventionally, one method of heat treating semiconductor substrates, etc. has been to irradiate and scan a fixed substrate with a linear electron beam whose cross section is approximately rectangular (linear). .

("Energy Beam Processing" edited by the Energy Beam Subcommittee of the Precision Machinery Society, Realize Inc., 1985, p. 268; "Collection of Proceedings of the 5th Recessed Functional Device Technology Symposium" New Functional Device Development Association, 1986, pp. 145-152) . In a conventional electron beam device, as shown in the schematic diagram of FIG. 2, a linear electron beam is focused on a sample 9, and the electron beam is deflected by a deflector 6 to scan over a wide range of the sample. , Sample 9 has been heat treated.

(Problems to be Solved by the Invention) However, the convergence state of the linear electron beam 4 is adjusted by the electron gun of the linear cathode 1, Wehnelt electrode 2, and anode 3, and the electron optical system of the lens 5 and deflector 6. However, because the linear electron beam is non-axisymmetric and the deflection width is large, it is difficult to control the linear electron beam to obtain a linear electron beam with good beam current density over a wide range. Therefore, for example, the electron beam annealing method was applied to 501 (Si1icon-On-1 nsulator
), when uniformly annealing the entire surface of a wafer of 2 inches or 4 inches or more, it is difficult to anneal over a wide area, which has been a major obstacle to practical application.

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems and provide a linear electron beam device that can evenly and uniformly heat-treat a large area by electron beam irradiation.

(Means for Solving the Problem) The linear electron beam device of the present invention is a means for passing the electron beam only through an opening and blocking the electron beam except for the opening, which is disposed in close proximity to the surface of the sample irradiated with the linear electron beam. a mask, and a moving mechanism as means for aligning the area of the sample to be irradiated with the electron beam with the irradiation position of the electron beam that has passed through the mask opening and sequentially transporting the area of the sample to be irradiated with the electron beam to the electron beam irradiation position. It consists of

(Function) According to the electron beam device of the present invention, the aperture width of the mask is made equal to or less than the maximum deflection width that allows a stable beam with extremely few aberrations, etc., and the sample is aligned with the irradiation position of the electron beam that has passed through the mask aperture. After that, by scanning a linear electron beam wider than the aperture width of the mask, the area to be heat treated by electron beam irradiation is exposed to the electron beam that has passed through the mask aperture, which is in a good condition with very little electron beam aberration. It can be limited to the irradiation area. After one more heat treatment by electron beam irradiation, the sample area to be heat treated next is moved so that it is within the electron beam irradiation area, and the procedure of irradiating and scanning the electron beam again to perform heat treatment by electron beam irradiation is repeated. Accordingly, the area to be heat-treated on the sample surface can be uniformly heat-treated by electron beam irradiation.

(Embodiment) FIG. 1 shows a main configuration diagram of an embodiment of the present invention.

Linear cathode 1 and Wehnelt electrode 2 in vacuum container 14
A linear electron beam 4 emitted from an electron gun consisting of an anode 3 and an anode 3 is imaged by a lens 5 onto a sample 9 as a linear electron beam. The imaged linear electron beam is scanned over the sample 9 by the deflector 6, but the linear electron beam is blocked by the mask 8, and the linear electron beam passes only through the open lower part of the mask, and the electrons that have passed through the open lower part of the mask are blocked by the mask 8. Heat treatment by the electron beam is performed only on the sample 9 in the beam irradiation area. At this time, both ends of the long side of the linear electron beam do not need to be cut. The sample 9 is placed in a sample holder 10 and preheated to, for example, about 600 DEG C. by a sample heater 13 or the like. Furthermore, the sample holder 10 is
2, the sample 9 is moved by the XY table drive system 11 so that the sample area to be heat treated by electron beam irradiation is located within the irradiation area of the electron beam that has passed through the mask opening lower, and the linear electron beam is is irradiated and heat treated.

After the heat treatment by electron beam irradiation, the sample 9 is moved so that the sample area to be heat treated is located within the irradiation area of the electron beam that has passed through the lower mask opening, and heat treatment is performed by electron beam irradiation. By repeating this process, a predetermined region of the sample can be evenly and uniformly heat-treated over a wide range with the electron beam.

(Effects of the Invention) As described above, according to the present invention, the area to be heat-treated by electron beam irradiation is limited to only the area where the linear electron beam is in good condition using a mask. elements can be reduced. In addition, the samples were
For example, heat treatment can be performed by uniformly irradiating a wide range of electron beams by moving the device intermittently. These effects can dramatically improve the yield of large-area heat treatment of large-diameter wafers and the like by electron beam irradiation.

[Brief explanation of the drawing]

FIG. 1 is an overall schematic diagram of an embodiment of the apparatus according to the present invention, and FIG. 2 is an overall schematic diagram of a conventional apparatus. In the figure, 1 is a linear cathode, 2 is a Wehnelt electrode, 3 is an anode,
4 is a linear electron beam, 5 is a lens, 6 is a deflector, 7 is a mask aperture, 8 is a mask, 9 is a sample, 10 is a sample holder,
11 is the XY table drive system, 12 is the XY table, 13
14 is a hot pot, 12 is a sample heating tape)

Claims (1)

[Claims] In a linear electron beam device, there is a mask which is placed close to the surface of the sample to be irradiated with the linear electron beam and serves as a means for allowing the electron beam to pass through only the aperture and blocking the electron beam in areas other than the aperture, and A line characterized by comprising a moving mechanism as a means for aligning the irradiation area with the irradiation position of the electron beam passing through the mask opening and sequentially transporting the area of the sample to be irradiated with the electron beam to the electron beam irradiation position. shaped electron beam device.