JPS63200454A - Linear electron beam device - Google Patents

Abstract

PURPOSE:To improve yield in large area heat treatment by disposing a mask just near a linear electron beam radiation surface of a sample so that electron beams are made to pass through only an aperture of the mask and they are interrupted in a region except for the aperture part, and by disposing heat shielding plates below the mask. CONSTITUTION:A sample 9 is mounted on a sample holder 10 and auxiliarily heated to a prescribed temperature by a sample heating heater 14 or the like. Heat loss due to radiation or the like between the sample and a mask is suppressed by a heat shielding plate 16. Further, in order to move the sample, for example, the sample holder 10 is mounted on a XY table 12, and the sample 9 is moved by a XY table driving system 11 so that the range which requires heat treatment by electron beam radiation is positioned at the part of the mask aperture 7, and then the linear electron beams are radiated to perform heat treatment. After the heat treatment is performed by the electron beam radiation, the sample 9 is moved so that the range of the sample, where heat treatment is next required, is positioned within the radiation region of electron beams which pass through the mask aperture 7, and again heat treatment is performed. When these procedures are repeated, heat treatment by electron beams can be performed uniformly without irregularity and over a wide range in the prescribed region of the sample.

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] Energy Beam Division Guidelines of the Precision Machinery Society, Realize, 1985, p. 26B; "Fifth Concave Functional Element Technology Symposium Proceedings" New Functional Element 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 a wide range of the sample. , Sample 9 has been heat treated.

(Problem 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, the Wehnelt electrode 2, and the anode 3, and the electron optical system of the lens 5 and the 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. there were. Therefore, for example, the electron beam annealing method is
), 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. The heat shielding plate is comprised of a mask, a means for heating the sample to a predetermined temperature, and a heat shielding plate installed between the mask and the sample and having an opening larger than the size of the mask shielding plate.

(Function) According to the linear electron beam device of the present invention, the aperture width of the mask is made equal to or less than the maximum deflection width at which a stable beam with extremely few aberrations can be obtained, and the sample is positioned at the irradiation position of the electron beam that has passed through the mask aperture. 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 made into a good irradiation area of the electron beam with extremely little aberrations etc. that have passed through the aperture of the mask. can be limited to. Furthermore, the heat shield plate blocks heat transfer due to radiation or the like between the preheated sample and the mask, thereby suppressing heat loss due to sample preheating, etc.

(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 13
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 portion of the mask; Heat treatment by the electron beam is performed only on the sample 9 in the area irradiated with the electron beam. The mask 8 may be cooled by the heat transfer effect of a water cooling pipe 15, for example, if necessary.The sample 9 is set in the sample holder 10, and heated to a predetermined temperature, for example, about 600°C, by a sample heater 14 or the like. It is preheated to
The heat shield plate 16 suppresses heat transfer due to radiation or the like between the sample 9 and the mask.

Furthermore, a mechanism for moving the sample may be provided, for example,
The sample holder 10 is set on the XY table 12, and
The sample 9 is moved by the table drive system 11 so that the processing range 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 sample 9 is irradiated with a linear electron beam and heat-treated. To restore 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 mask opening lower, 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, and unstable elements can be reduced. Further, since the sample is sequentially moved, for example, by an intermittent movement method, it is possible to perform heat treatment by uniform electron beam irradiation over a wide range. In addition, the heat shield plate suppresses heat transfer due to radiation between the sample and the mask, thereby increasing the thermal efficiency of sample preheating, etc., and making it easier to uniform the temperature distribution within the sample surface during sample preheating. Due to the above-mentioned effects, the yield of large-area heat treatment by electron beam irradiation of large-diameter wafers and the like can be dramatically improved.

[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 the 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 an aperture, 8 is a mask, 9 is a sample, 10 is a sample holder, 11 is an XY table drive system, 12 is an XY half 1 Figure 4, Urasu Sawaden) Pim 1. de1
History Kando 11, XY Qiful Gegu v7 Mu

Claims (1)

[Claims] In a linear electron beam device, a mask is placed in close proximity to the linear electron beam irradiation surface of the sample, and serves as a means for passing the electron beam through only the opening and blocking the electron beam in areas other than the opening, and a mask that is used to heat the sample to a predetermined temperature. It is characterized by comprising a means for heating, and one or more heat shielding plates installed between the mask and the sample and having an opening of the same size or larger than the opening of the mask. Linear electron beam device.