JPH07105320B2 - Electronic beam drawing device sample placement device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sample mounting device of an electron beam drawing apparatus.

The sample drawn by the electron beam drawing apparatus is usually a glass mask or a wafer. In the case of a glass mask, the sample is set in a holder and loaded on the stage. When the glass mask is set in the holder, its periphery is fixed to the holder, so that the glass mask is bent due to its own weight. This deflection causes a positional error in the vertical direction of the drawing surface and deteriorates the accuracy, and especially in the case of a large glass mask, the deflection amount becomes a value far exceeding the depth of focus of the electron beam. There is also a method of pressing a glass mask against a highly accurate reference plate as is done with wafers,
It is necessary to increase the rigidity of the reference plate, and the weight of the holder becomes heavy and large.

[Prior art]

Therefore, there is a conventional sample placing device for correcting the vertical position of the glass mask, and an example thereof will be described with reference to FIG. A moving stage 13 that is moved by a drive source 12 is provided in the sample chamber 11 that is a vacuum at the time of drawing, and a mounting stage 15 is provided on the moving stage 13 via a pair of piezo elements 14 and 14. A glass mask 18 supported by a holder 17 is mounted on a mounting stage 15 via a clamp mechanism 16. An electron beam 19 from a lens barrel (not shown) above the sample chamber 11 is irradiated onto the glass mask 18 under the control of the dynamic focus coil 20, the focusing coil 21, the deflecting plate 22 and the like and is drawn.

On the other hand, the vertical position of the glass mask 18 is corrected by irradiating the glass mask 18 with the laser light emitted from the He-Ne laser light source 26 through the window 27 through the laser interferometer 28 and the bender 29, and the reflected light is the opposite of the above. To the receiver 30 through the bender 29, laser interferometer 28 and window 27. The signal from the receiver 30 is supplied from the amplifier 31 through the variable power source 32 to the piezo element 14 to expand and contract it, and the glass mask through the mounting stage 15.
Correct by moving 18 up and down.

It seems that the vertical position of the glass mask 18 can be corrected even with such a sample placing device, but when the glass mask is recently enlarged to reach 10 inches (about 254 mm), the center portion of the glass mask supported on the periphery is The deflection is as large as 0.1 mm. However, in the conventional electron beam drawing apparatus, the glass mask 18
I am drawing while correcting the vertical position of the drawing part of, but 0.
In the case of correction of 1 mm, expansion and contraction of the piezo element 14 requires a certain amount of time, so that the correction is actually performed in an insufficient state and the accuracy is lowered. Further, there is a drawback that the mechanism is complicated because the entire mounting stage is finely moved, and that since continuous control is performed for a large drawing area, it is complicated and the cost is high.

Further, instead of the mechanism for moving the vertical position of the glass mask 18 by the piezo element 14 to correct it, the position of the upper surface of the glass mask is measured by the Z sensor and the current of the dynamic focus coil 22 is adjusted in proportion to the position. Glass mask 18
There is a method to focus the electron beam on the upper surface of. However, this method also has a drawback that the beam position, the beam size, and the like become unstable because the electron beam is constantly controlled.

[Object of the Invention]

The present invention eliminates such drawbacks and its purpose is to
Even if the size of the glass mask becomes large and the deflection due to its own weight becomes large, the deflection is removed by one correction to improve the drawing accuracy, and the cost is reduced by eliminating the continuous correction by one correction and reducing the cost. It is to provide a mounting device.

[Main points of the invention]

The sample placing device of the electron beam drawing apparatus according to the present invention is
A holder for detachably supporting the glass mask, a reference piece for height position regulation which is arranged on the holder and receives a plurality of locations near the periphery of the upper surface of the glass mask, and the glass mask can be pressed against the reference piece. In a sample placing device of an electron beam drawing apparatus comprising a spring provided in the holder and a placing stage that holds the holder in a detachable manner, a sample is attached to the placing stage so as to be movable up and down by a spring. A reference plate, which is pressed against the glass mask side and is capable of contacting a reference stopper for height position regulation provided on the mounting stage, and a reference plate of the glass mask that faces the lower surface of the glass mask. It is located near the center and is attached to the holder so that it can move up and down. When the holder is held on the mounting stage, it is located above the reference plate and above the reference plate. Is characterized by comprising a predetermined amount pushes up spacers inboard lower surface of the glass mask by.

Example of Invention

An embodiment of the present invention will be described below with reference to FIG.
The mounting stage 41 is installed on a moving stage (not shown) similar to the moving stage 13 provided in the sample chamber 11 shown in FIG. 4, and a clamp piece 42 is attached to the upper surface thereof. . A holder 44 whose central portion is removed is pressed by the spring 43 onto the raised portion of the clamp piece 42 and clamped, and the glass mask 18 is pressed against the reference piece 45 fixed to the upper surface of the holder 44 by the spring 46. It is supported. A holder 47 is attached to the holder 44, and the holder 47 holds a plurality of pins 48 of equal length,
The tip of this pin 48 can be brought into contact with the lower surface of the glass mask 18.

A lever 49 rotatably supported by the mounting stage 41 is provided in the cavity of the mounting stage 41, and the upper surface of the reference plate 50 rotatably attached to one end of the lever 49 has the lever 49 with respect to the lower end of the pin 48.
Is pressed by a spring 51 provided near the other end of the. Further, three epizo elements 52, one side of which is in contact with it, are embedded in the reference plate 50 (only two are shown in the drawing, and the other one is at the apex position forming a regular triangle together with the two). , Piezo element
The other side of 52 is in contact with a reference stopper 53 fixed to the upper surface of the mounting stage 41.

The measurement for correcting the vertical position (Z direction) of the glass mask 18 is the same as in the conventional example, and the laser light emitted from the He-Ne laser light source 26 enters the lens barrel 56 from the window (not shown) of the sample chamber. The glass mask 18 is irradiated through the fixed laser interferometer 28 and the bender 29, and the reflected light is, on the contrary, the bender 2
9. Laser interferometer 28 and then through window to receiver 30. The signal from the receiver 30 is expanded and contracted by the piezoelectric element 52 from the amplifier 31 through the variable power source 32.

Next, the operation of the above-described embodiment will be described. When the glass mask 18 supported by the holder 44 is loaded on the mounting stage 41, first, the vicinity of the reference piece 45 which is in contact with the upper surface of the glass mask 18 is measured by laser light to make it a zero point. , Then moving stage (not shown, see FIG. 4)
The laser light to the glass mask by moving the X and Y directions.
Irradiate almost the center of 18. The reflected light at this time is the receiver
The signal enters 30 and is applied to the piezo element 52 via the amplifier 31 and the variable power source 32. As a result, the piezo element 52 expands and contracts according to the signal value. Reference plate when the piezo element 52 extends
The glass mask 18 also descends because 50 descends and the pins 48 descend, and when the piezo element 52 contracts, the reference plate 50 ascends and thus the glass mask 18 as well. In this way, the central portion of the glass mask 18 is flush with the peripheral support portion of the glass mask 18. At this time, the unevenness of the glass mask 18 is only the deflection due to its own weight while being supported by the peripheral support portion and the pin 48, and the amount can be suppressed to several μm or less.

The reference plate 50 is pushed down by an unclamp mechanism (not shown) when the holder 44 is loaded or unloaded. The reference plate 50 is supported by a lever 49 and a spring 51, and may be inserted into a cylinder (not shown) so that a spring (not shown) is arranged on the lower surface thereof. May be increased or decreased depending on the size of
Furthermore, if the thickness of the glass mask 18 changes and the change exceeds the adjustment range of the piezo element 14, the pin 48 may be replaced to deal with it.

FIG. 2 shows the essential parts of the second embodiment of the present invention. In this example, a ring 61 is used instead of the pin 48 of the first embodiment, and a ring 61 and a washer 63 are alternately inserted into a shaft 62 between the glass mask 18 and the reference plate 50, and the shaft 62 is inserted. A snap ring 64 is attached near both ends to prevent the ring 61, etc. from coming off. Except for the illustration, it is the same as the first embodiment.

FIG. 3 shows an essential part of a third embodiment of the present invention, in which a flat plate 66 is arranged instead of the pin 48 of the first embodiment, and is the same as the first embodiment except for the illustration. is there. The pin 48 of the first embodiment, the ring 61 of the second embodiment, and the third
The flat plate 66 of the embodiment is generically called a spacer.

〔The invention's effect〕

As described above, the sample placing apparatus of the electron beam drawing apparatus according to the present invention measures the height position of the glass mask by the Z sensor when the holder supporting the glass mask is loaded on the placing stage, and the position is set at that position. Accordingly, the height of the reference plate was adjusted to correct the position of the glass mask. At this time, the glass mask became flat by pushing up the central portion of the lower surface and a wider range according to the area, and the entire area could be drawn with one correction. Therefore, there is an advantage that the accuracy is improved because it is not necessary to perform the drawing while performing the correction as in the conventional technique, and the cost is reduced because the correction is performed once without the need for continuous correction.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 and FIG.
The drawings are partial cross-sectional views of other different embodiments of the present invention.
FIG. 4 is a sectional view of a conventional example. 18 …… Glass mask, 41 …… Mounting stage, 42 …… Clamp piece, 44 …… Holder, 46,51 …… Spring, 48,61,66…
… Spacer, 50 …… Reference plate, 52 …… Piezo element

Claims (6)

[Claims] 1. A holder for detachably supporting a glass mask, a reference piece for height position regulation which is arranged on the holder and receives a plurality of positions near the periphery of the upper surface of the glass mask, and the glass mask as the reference. In a sample placing device of an electron beam drawing apparatus comprising a spring provided in the holder so as to be able to press against one piece and a placing stage holding the holder in a detachable manner, the sample stage can be moved up and down on the placing stage. A reference plate, which is attached and pressed to the glass mask side by a spring and is capable of abutting against a reference stopper for height position regulation provided on the mounting stage, faces the lower surface of the glass mask. Therefore, it is arranged below the center of the glass mask and is attached to the holder movably up and down. When the holder is held on the mounting stage, it is located above the reference plate. Sample supporting means of the electron beam drawing apparatus, characterized in that the inboard lower surface of the glass mask by the rise of the reference plate; and a predetermined amount pushes up the spacer. 2. The sample placing device of the electron beam drawing apparatus according to claim 1, wherein the spacer is replaceable according to the thickness of the glass mask. 3. A sample placing device for an electron beam drawing apparatus according to claim 1, wherein a pin-shaped spacer is used as the spacer. 4. A sample mounting device for an electron beam drawing apparatus according to claim 1, wherein a ring-shaped spacer is used as the spacer. 5. A sample mounting device for an electron beam drawing apparatus according to claim 1, wherein flat spacers are used as the spacers. 6. A reference plate is provided with three piezo elements, one side of the piezo elements is brought into contact with a reference stopper fixed on a mounting stage and the other side is brought into contact with the reference plate, and the piezo element is also attached. The sample placing device of the electron beam drawing apparatus according to claim 1, wherein the height of the contact surface with the spacer is adjusted by changing the input voltage of the element.