Electron beam fine processing device

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Field to which the invention belongs]

The present invention relates to an electron beam microfabrication apparatus, and in particular, an electron beam microfabrication apparatus including a horizontal motion stage and a rotary motion stage, capable of creating a concentric circular arrangement pattern on a workpiece placed on the rotary motion stage. It is about.

【0002】

[Conventional technology]

In an electron beam microfabrication apparatus represented by an electron beam drawing apparatus, a pattern is formed (processed) by scanning a finely focused electron beam and sequentially irradiating a target position on a sample substrate. When processing a concentric circle arrangement pattern in which concentric circles are arranged by a conventional electron beam microfabrication apparatus, a biaxial horizontal motion stage is used and the so-called step-and-repeat method is used. This step-and-repeat method is a method in which a pattern to be machined is divided into a grid pattern, and a part of the arc is sequentially machined and joined. It takes an enormous amount of processing time and is joined at the joining position. Due to the error, it was impossible to process the nanometer area.

【0003】

There was a device that used a rotary motion stage to process a concentric circle arrangement pattern, but in a device that did not correct the position disturbance due to the eccentricity of the rotary motion stage, there was uncertainty in the machining position corresponding to the amount of eccentricity. .. The amount of this uncertainty is as large as 300 nanometers (nm) even on a well-performing rotary stage. Further, the method of performing the correction by mechanically horizontally moving the center position of the rotary moving stage has a slow correction response speed and cannot cope with the processing of a high-density pattern by an electron beam.

【0004】

[Problems to be Solved by the Invention]

In view of the above-mentioned problems of the prior art, the present invention corrects the position of the electron beam irradiated to the workpiece to obtain minute periodic eccentricity and aperiodic eccentricity generated with each rotation of the rotary motion stage. It is an object of the present invention to provide an electron beam microfabrication apparatus capable of rapid correction.

【0005】

[Means for solving problems]

In order to achieve the above object, the present invention measures the position of the horizontal moving stage in an electron beam fine processing apparatus including a horizontal moving stage and a rotating moving stage and forming a circular pattern on a workpiece on the rotating moving stage. It is equipped with a first measuring instrument to measure and a second measuring instrument to measure the amount of eccentricity during rotation in the rotating dynamic stage, and the voltage value of the electron beam deflector is calculated based on the measured values of the first measuring instrument and the second measuring instrument. It is characterized in that it is adjusted so that the correction control of the irradiation position of the electron beam is performed.

【0006】

According to the present invention, the position of the horizontal moving stage is measured by a first measuring instrument, for example, a non-contact length measuring instrument. A plurality of second measuring instruments, for example, non-contact displacement meters, are provided around the rotating shaft of the rotating stage to measure the amount of eccentricity of the rotating stage. The eccentric motion of the rotational stage has periodic eccentricity and aperiodic eccentricity, but the periodic eccentricity is measured in advance using the second measuring instrument. By associating the angular information of the rotary encoder with the periodic eccentricity, the periodic eccentricity is stored in the storage device as a function of the angle.

【0007】

When electron beam processing a concentric circle arrangement pattern on a workpiece placed on a rotary motion stage, the amount of misalignment of the horizontal motion stage, the amount of eccentricity of the periodic eccentricity of the rotary motion stage, the periodic eccentricity and the time of the machining The aperiodic eccentricity, which is the difference in the amount of eccentricity, is added to obtain the correction amount, and the amount is returned to the operating amount of the electron beam deflector so as to correct the electron beam position. In this way, the position information of the horizontal moving stage and the eccentricity of the rotating moving stage are returned to the electron beam deflector to correct the electron beam position in real time, thereby improving the machining accuracy and machining speed. Can be done.

【0008】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, examples of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an overall configuration of an electron beam microfabrication apparatus according to the present invention. As shown in FIG. 1, the electron beam microfabrication apparatus includes an irradiation system 1 and a processing chamber 2 arranged below the irradiation system 1. The irradiation system 1 is composed of an electron gun 4, a first electromagnetic lens 5, a second electromagnetic lens 6, an electron beam deflector 7, and the like housed in the mirror body 3. The inside of the mirror body 3 and the processing chamber 2 is exhausted by a vacuum exhaust system (not shown) arranged below the processing chamber 2 and equipped with a vacuum pump, and is maintained at a predetermined degree of vacuum.

【0009】

A horizontal moving stage 8 is installed in the processing chamber 2, and a rotary encoder 9 is installed on the horizontal moving stage 8. The horizontal moving stage 8 has a structure in which the stage can be moved in the directions of two axes (X and Y axes) orthogonal to each other and the stage can be positioned at a desired position on the horizontal plane. A rotary stage 10 is arranged on the rotary encoder 9. The rotary drive stage 10 is driven by the rotary drive stage driver 17. The rotary moving stage 10 has a structure in which the stage can rotate at a desired rotation speed around its own rotation axis. Non-contact displacement meters 11 to 15 are arranged around a rotating stage 10 on a predetermined circumference at predetermined intervals. A laser mirror 23 is fixed to the horizontal moving stage 8, and the laser mirror 23 is irradiated with a laser from a laser transmitter 22 arranged outside the processing chamber 2. A glass window 2W for transmitting laser light is provided on the side wall of the processing chamber 2.

【0010】

The electron gun 4 is connected to the electron gun control unit 33, and the first electromagnetic lens 5 and the second electromagnetic lens 6 and the like are connected to the irradiation system control unit 32. Further, the deflector 7 is connected to the operational amplifier 28, and the graphic information memory unit 30 and the graphic information processing unit 31 are connected to the operational amplifier 28 in series.

【0011】

The non-contact displacement meters 11 to 15 are connected to the non-contact displacement meter control unit 20, respectively, and the non-contact displacement meter control unit 20 is connected to the operational amplifier 28 via operational amplifiers 21, 26, and 27, respectively. The rotary encoder 9 is connected to the encoder reading unit 18, and the encoder reading unit 18 is connected to the function generator 25. Further, the encoder reading unit 18 and the rotary stage driver 17 are interconnected. The function generator 25 is connected to the operational amplifier 26 and the operational amplifier 27. On the other hand, the laser transmitter 22 is connected to the laser interference length measuring device 24, and the laser interference length measuring device 24 is connected to the operational amplifier 27.

【0012】

In the above configuration, the electron beam emitted from the electron gun 4 is focused by the first electromagnetic lens 5 and the second electromagnetic lens 6, and then the workpiece 40 is placed on the rotary moving stage 10 through the deflector 7. Is irradiated to, and the workpiece 40 is processed. In this case, the circular pattern or the concentric arrangement pattern is formed (processed) by rotating the rotary motion stage 10 around its own rotation axis while irradiating a predetermined position on the workpiece with an electron beam. The laser transmitter 22, the laser mirror 23, and the laser interference measuring instrument 24 constitute the first measuring instrument for measuring the position of the horizontal moving stage 8, and the non-contact displacement meters 11 to 15 are eccentric during rotation in the rotating moving stage 10. It constitutes a second measuring instrument that measures the amount.

【0013】

While the rotary motion stage 10 is rotating, the non-contact displacement meters 11 to 15 arranged around the rotary motion stage 10 are relative to the reference plane of the rotary motion stage 10 and the non-contact displacement meters 11 to 15. Continue to measure the target displacement. The data measured by the non-contact displacement meters 11 to 15 is collected by the non-contact displacement meter control unit 20 and transmitted to the operational amplifier 26 through the operational amplifier 21. The output of the rotary encoder 9 of the rotary motion stage 10 is read by the encoder reading unit 18, converted into an angle, and then transmitted to the function generator 25. The periodic eccentricity of the rotary stage 10 is obtained by the non-contact displacement meters 11 to 15, and by associating the angular information of the rotary encoder 9 with the periodic eccentricity, the periodic eccentricity is used as a function of the angle in the function generator 25. Store in advance. The function generator 25 outputs the periodic eccentricity corresponding to the angle information sent from the rotary encoder 9 to the operational amplifier 26 and the operational amplifier 27 based on the stored function value. The operational amplifier 26 compares and calculates the signal of the function generator 25 and the signal from the operational amplifier 21, and outputs the difference as an aperiodic eccentric amount to the operational amplifier 27.

【0014】

On the other hand, the laser light emitted from the laser transmitter 22 is reflected by the laser mirror 23 fixed on the horizontal moving stage 8, and this reflected light is received by the laser interference length measuring device 24. As a result, the position of the horizontal moving stage 8 is measured, and the measured value is transmitted to the operational amplifier 27. The operational amplifier 27 is required to calculate the amount of deviation from the desired position from the periodic eccentricity and the aperiodic eccentricity of the rotary motion stage 10 and the position information of the horizontal motion stage 8 and correct the deviation amount. Output voltage or current.

【0015】

The information from the graphic information memory unit 30 is converted into an electric signal corresponding to the amount of electron beam deflection by the graphic information processing unit 31 and transmitted to the operational amplifier 28. The signal from the operational amplifier 27 and the signal from the graphic information processing unit 31 are finally processed by the operational amplifier 28 and transmitted to the deflector 7. By this series of processing, the position information of the horizontal moving stage 8 and the eccentricity of the rotating moving stage 10 are returned to the deflector 7, and the electron beam is desired on the workpiece on which the rotating moving stage 10 is placed. The voltage value of the deflector 7 is adjusted so as to irradiate the position, and as a result, the electron beam position control corresponding to the desired graphic information and the electron beam position that cancels the position fluctuation of the horizontal moving stage 8 and the rotating moving stage 10 are canceled. It is possible to perform correction control at the same time.

【0016】

[Effect of the invention]

As described above, according to the electron beam microfabrication apparatus of the present invention, the position of the electron beam irradiated to the workpiece can be corrected, so that a minute periodic eccentricity that occurs with each rotation of the rotary motion stage And the aperiodic eccentricity can be corrected quickly. Therefore, a smooth circumferential pattern without meandering can be processed on the workpiece.

[Simple explanation of drawings]

[Figure 1]

It is a block diagram which shows one Embodiment of the electron beam microfabrication apparatus which concerns on this invention.

[Explanation of symbols]

1 Irradiation system 2 Processing room 2W glass window 3 Mirror body 4 electron gun 5 1st electromagnetic lens 6 Second electromagnetic lens 7 deflector 8 Horizontal movement stage 9 Rotary encoder 10 rotary stage 11,12,13,14,15 Non-contact displacement meter 17 Rotating stage driver 18 encoder reading unit 20 Non-contact displacement meter control unit 21,26,27,28 Op amp 22 laser transmitter 23 laser mirror 24 Laser coherence measuring instrument 25 Function generator 30 Graphic memory unit 31 Graphic information processing unit 32 Irradiation system control unit 33 Electron gun control unit 40 Work piece