JPH01241121A - Electron-beam exposure system - Google Patents

Abstract

PURPOSE:To prevent the generation of vibrations approximately by making a stage reach to a speed change point and specified speed accurately at the detecting period of an ideal locus by preparing a travelling predetermined locus so that the acceleration start time and the acceleration finish time coincide with the detecting period of a travelling locus. CONSTITUTION:A main CPU 1 for preparing the data of an ideal orbit, a CPU 2 for controlling a stage, a laser length measuring machine controller 3, a motor drive section 4, a laser transducer 5, a mirror 6, a motor 7 and a stage 8 are installed, and operated previously by software. A travelling predetermined locus is formed so that the acceleration start time and the acceleration finish time coincide with the detecting period of the desired travelling locus of the stage 8. Accordingly, the stage 8 accurately reaches to a speed change point and specified speed at the detecting period of the desired travelling locus, and the detection of the travelling locus after the stage 8 passes through the speed change point and specified speed is prevented approximately, thus nearly obviating vibrations.

Description

[Detailed Description of the Invention] [Summary] To provide an electron beam exposure device in which a stage can reach a speed change point and a specified speed exactly at the detection cycle of an ideal trajectory, and almost no vibration occurs. For this purpose, when stage movement is controlled by digital software, a desired travel trajectory is held in advance in the software, and the position, velocity, and acceleration are adjusted to the travel trajectory at regular intervals.In the electron beam exposure apparatus, acceleration is started. A planned travel trajectory is created such that the time and acceleration end time match the detection cycle of the travel trajectory.

[Industrial application field]

The present invention relates to an electron beam exposure apparatus, and more particularly to an electron beam exposure apparatus that can prevent vibration (hunting) from occurring.

2. Description of the Related Art In recent years, a continuously moving stage type electron beam exposure apparatus, which performs exposure while continuously moving a stage, has been attracting attention. This is because photoetching technology that uses light (ultraviolet light) has reached its limit, so it attempts to use an electron beam with a short wavelength, which is suitable for microfabrication.

[Conventional technology]

There are two types of stage control methods for electron beam exposure apparatuses: analog control and digital software control. Digital software control is superior in terms of size, cost, and flexibility.

When controlling stage movement using digital software, the desired stage trajectory as shown in Figure 5 is maintained as an ideal trajectory in advance in the software in the form of a speed of 1 degree as a function of time and distance. (Then, the actual movement of the stage is detected in the form of an error from the ideal trajectory at a certain period (detection period), and the stage is moved by controlling the motor to correct the error. The trajectory is determined according to the user's wishes.

[Problem to be solved by the invention]

However, in such a conventional electron beam exposure apparatus, the ideal orbit has a certain period (as shown in FIG. 6).
There was a problem in that the stage almost never reached the speed change point (Xl, . Specifically, for example, the designated speed is exceeded as shown in B, and the speed change point X2 is exceeded as shown in C. There is also the problem that vibration (hunting) is likely to occur if an attempt is made to forcibly adjust the trajectory to the ideal trajectory after passing the speed change point and designated speed.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electron beam exposure apparatus in which the stage can reach a speed change point and a designated speed exactly during the detection cycle of the ideal trajectory, and almost no vibration occurs.

[Means to solve the problem]

In order to achieve the above object, the electron beam exposure apparatus according to the present invention, when controlling stage movement using digital software, stores a desired travel trajectory in advance in the software, and changes the position, velocity, and acceleration to the travel trajectory at regular intervals. In the matching electron beam exposure apparatus, a scheduled travel trajectory is created such that the acceleration start time and acceleration end time coincide with the detection cycle of the travel trajectory.

In the present invention, the acceleration start time and acceleration end time refer to the start time and end time of positive acceleration, and the start time and end time of negative acceleration (: $i speed). This includes the following aspects.

[For production]

In the present invention, the planned travel trajectory is created such that the acceleration start time and acceleration end time match the detection cycle of the desired travel trajectory of the stage.

Therefore, the stage reaches the speed change point and the specified speed exactly at the detection cycle of the desired traveling locus, and it is almost impossible to detect the stage after passing the speed change point and the specified speed.

〔Example〕

Hereinafter, the present invention will be explained based on the drawings.

FIG. 1 is a schematic diagram showing the configuration of an embodiment of an electron beam exposure apparatus according to the present invention, and FIG. 2 is an ideal trajectory (corresponding to the desired traveling trajectory according to the present invention) and a planned traveling trajectory of the embodiment. FIG. 3 is a flowchart showing the control details of the main CPU in one embodiment, and FIG. 4 is a flowchart showing the control details of the stage control CPU in one embodiment.

In these figures, 1 is the main CPU, which can function as a computer for creating ideal trajectory data. 2 is a stage control CPU, 3 is a laser length measuring device control section, 4 is a motor drive section, 5 is a laser transducer, 6 is a mirror, 7 is a motor, and 8 is a stage.

Next, the principle of operation will be briefly explained using FIG.

First, for example, position, velocity, and acceleration data every l m s are created as an ideal trajectory by the upper main CPU so that the velocity change point and the position, velocity, and acceleration detection time match, and transferred to the stage control CPU 2. . The stage control CPU 2 controls the rotation of the motor 7 to move the stage 8 in order to correct the error from the ideal trajectory whose position, velocity, and acceleration are detected every 1 ms.

Next, the ideal trajectory M (solid line) and the planned travel trajectory N (dashed line) will be specifically explained using FIG.

First, when creating the planned travel trajectory N, the main CPU
The speed change point and acceleration specified in are processed and adopted. As shown in FIG. 2, the speed change point is shifted to match the stage position in the detection period.

That is, the planned travel trajectory N is created so that the acceleration start time t1 and the acceleration end time t2 match the detection period A of the ideal trajectory M (other acceleration start times and acceleration end times are made to match in the same way). When performing exposure while moving the stage 8, if x2 is the next acceleration, it is shifted backwards, and X, if the next one is deceleration, it is shifted forward. For example, the acceleration is x, as shown by ■7°, -v, = a, t (t is the detection time) a
.

is maximum within the allowable range (inside the ideal trajectory M,
and the detection point matches the detection period A of the ideal trajectory iM)
Select as appropriate.

Next, the operating principle of the main CPUI and the stage control CPU 2 will be specifically explained using FIGS. 3 and 4.

First, on the main CPU, create an ideal trajectory M as shown in Figure 2.
Create. Specifically, conditions such as exposure amount and amplifier stabilization time are set based on the P+ pattern data shown in Figure 3.
2, the moving speed of the stage 8 is calculated with P, and based on this, a stage moving trajectory of the speed and speed change points is created in P4.

Next, an i-light schedule is created at P5 based on this stage movement trajectory. Here, the exposure schedule is necessary to provide movement data for one wafer or several wafers. Then, at P6, stage movement data (speed and speed change point data) and other information are transferred to the stage control CPU 2 as a command.

Next, the stage 8 is controlled by the stage control CPU 2. Specifically, the speed of the ideal trajectory with Sl shown in Figure 4 is
is initially set (vK=0), and VK=VK+α(
acceleration) and (position of ideal trajectory) Px = Px ”VjI+
A function such as α is generated to calculate the target position. Next, in S3, the position information of the stage 8 (actual position data P1,) is read, and in S4, the deviation amount (PK
P r+c) is calculated, and based on this deviation amount S
, calculates the servo operation amount and controls the rotation of the motor 7.

Note that the stage control CPU 2 operates at regular intervals, for example, every 1 mS.

That is, in the above embodiment, the planned running trajectory N was created so that the acceleration start time and the acceleration end time coincided with the detection cycle of the ideal trajectory M, so stage 8 was exactly at the speed change point and the specified speed change point in the detection cycle of the ideal trajectory M. The speed will always be reached, and it will almost never be detected after passing the speed change point or specified speed. In addition, after passing the speed change point and specified speed, the ideal trajectory M
There is no need to adjust to the current level, and almost no vibration occurs.

〔effect〕

According to the present invention, the stage can reach the speed change point and the designated speed exactly during the detection period of the ideal trajectory, and vibrations are hardly generated.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the configuration of an embodiment of an electron beam exposure apparatus according to the present invention, FIG. 2 is a diagram illustrating an ideal trajectory and a planned running trajectory of an embodiment, and FIG. 3 is an embodiment of an embodiment. Fig. 4 is a flowchart showing the control details of the stage control CPtJ of one embodiment, Fig. 5 is a diagram showing the ideal trajectory of the conventional example, Fig. 6 is the problem of the conventional example. FIG. ■・・・・・・Main CPU. 2... Stage control CPU, 3...
Laser length measuring device control unit, 4...Motor drive unit, 5...Laser transducer, 6...
・Mirror, 7...Motor, 8...Stage. Elephant; Fig. 1 Fig. 4 Jusong dynasty 1 J Pi 4 Imperial Dao 2 Indicating mouth Fig. 5 Funeral ceremony 1 A-drop station number and friends e month) Ru mouth Fig. 6

Claims (1)

[Claims] In an electron beam exposure apparatus, when stage movement is controlled by digital software, a desired travel trajectory is held in advance by the software, and the position, velocity, and acceleration are adjusted to the travel trajectory at regular intervals. An electron beam exposure apparatus characterized in that a scheduled traveling trajectory is prepared such that a start time and an acceleration end time coincide with a detection cycle of the traveling trajectory.