JPS6231834A - Shutter control device - Google Patents
Shutter control deviceInfo
- Publication number
- JPS6231834A JPS6231834A JP60169854A JP16985485A JPS6231834A JP S6231834 A JPS6231834 A JP S6231834A JP 60169854 A JP60169854 A JP 60169854A JP 16985485 A JP16985485 A JP 16985485A JP S6231834 A JPS6231834 A JP S6231834A
- Authority
- JP
- Japan
- Prior art keywords
- shutter
- motor
- light
- section
- light passing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
- G03F7/7055—Exposure light control in all parts of the microlithographic apparatus, e.g. pulse length control or light interruption
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Shutters For Cameras (AREA)
- Projection-Type Copiers In General (AREA)
- Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
- Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明はシャッター制御装置に係り、特に縮小投影露光
装置のシャッターのように、露光時間を微小な分解能か
つ高い精度で設定することが要求される場合や極めて高
温の周囲条件下で使用される場合に好適なシャッター制
御装置に関する。[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a shutter control device, and in particular, it is required to set the exposure time with minute resolution and high precision, such as the shutter of a reduction projection exposure device. The present invention relates to a shutter control device suitable for use in high temperature environments and in extremely high temperature ambient conditions.
縮小投影露光装置のシャッターは、露光時間を微小な分
解能かつ高い精度で設定することが要求され、また照明
光源による極めて高温の下で使用され−ることがら、シ
ャッターをステッピングモーターや直流電動機で回転さ
せる簡単な構成のものが使用されている。The shutter of a reduction projection exposure system is required to set the exposure time with minute resolution and high precision, and because it is used under extremely high temperatures caused by the illumination light source, the shutter is rotated by a stepping motor or DC motor. A simple configuration is used.
縮小投影露光装置のスループット向上策の一つに露光時
間の短縮がある。そのためには高速度のシャッターが必
要である。One way to improve the throughput of a reduction projection exposure apparatus is to shorten the exposure time. This requires a high-speed shutter.
シャッター高速化の方策としては、従来、参考文献［ス
テッパにおける機構と制御 高橋−雄昭和６０年度精機
学会春季大会シンポジウムテキスト」に見られるように
、シャッターの形状や材質を考慮することにより、その
慣性を小さくする方法がとられて来ている。As a measure to increase the speed of the shutter, conventional measures have been taken to increase its inertia by considering the shape and material of the shutter, as seen in the reference document ``Mechanism and control in steppers: text of the 1985 Spring Conference of the Japan Society of Precision Machinery Society Symposium by Yu Takahashi''. Measures have been taken to reduce the size of the
しかし、さらに高速化をはかるためには、駆動モーター
として、より高速化に適した直流モーターを使用し、し
かもその能力を最大限に発揮させる制御を行なう必要が
ある。However, in order to achieve even higher speeds, it is necessary to use a DC motor, which is more suitable for higher speeds, as the drive motor, and to control it to maximize its performance.
また、シャッターの構造上、直流モーター、速度を検出
するための速度計発電機、回転角度を検出するためのパ
ルスエンコーダー等、制御に必要な器具や部品は光路を
妨害する障害物となるので。Additionally, due to the structure of the shutter, equipment and parts necessary for control, such as a DC motor, a speedometer generator to detect speed, and a pulse encoder to detect rotation angle, become obstacles that obstruct the optical path.
可能な限り省いて簡素化しなければならない。It must be simplified and omitted as much as possible.
本発明の目的はシャッターの高速化を図ったシャッター
制御装置を提供することにある。An object of the present invention is to provide a shutter control device that increases the speed of the shutter.
本発明の特徴は円周に沿って光通過部と光遮断部を設け
たシャッターと、前記光通過部および光遮断部を選択的
に光束位置に切換えるように前記シャッターを回転する
モーターと、前記光束位置に前記光通過部および光遮断
部のうちの一方が切換えられている状態から他方が切換
えられるまでの期間の前半部分においては前記モーター
を等加速度的に増速し、後半部分においては前記モータ
ーを等加速度的に減速するように前記モーターの回転を
制御する手段とを備えているシャッター制御装置にある
。The features of the present invention include a shutter provided with a light passing section and a light blocking section along the circumference, a motor rotating the shutter so as to selectively switch the light passing section and the light blocking section to light flux positions, and During the first half of the period from when one of the light passing section and the light blocking section is switched to the light flux position until the other is switched, the motor is accelerated at a constant rate, and during the second half, the motor is accelerated at a constant rate. and means for controlling the rotation of the motor so as to decelerate the motor at a uniform rate.
第１図は本発明の一実施例を示す図である。１は円板状
のシャッターを示す１図はシャッターが、その円周に沿
って４個の切欠き部すなわち光通過部を備える場合の例
を示す、１１の点線で示した円は光束の断面であり、図
はシャッターが光を遮断した場合を示している。シャッ
ターが図の角度θだけ回転すると、切欠き部が光束の位
置に来るので、シャッターは開状態になる。FIG. 1 is a diagram showing an embodiment of the present invention. Figure 1 shows a disc-shaped shutter. Figure 1 shows an example where the shutter has four notches, or light passage parts, along its circumference. The circle indicated by the dotted line in 11 is the cross section of the light beam. The figure shows the case where the shutter blocks light. When the shutter rotates by the angle θ shown in the figure, the notch comes to the position of the light beam, so the shutter becomes open.
１′はシャッターを側面から見た図であり、これ直流モ
ーター２によって駆動されることを示している。３は増
巾器で直流モーター２を駆動する。1' is a side view of the shutter, showing that it is driven by a DC motor 2. 3 is an amplifier that drives the DC motor 2.
４は方形波信号発生器で、その出力は増巾器３の入力と
なる。５はシャッターの開閉指令信号で方形波信号発生
器４の入力となる。６は電流検出器であり、本例では抵
抗器を使用している。この抵抗器の両端の間に、直流モ
ーター２の電流に比例した電圧が得られるので、これを
前記増巾器３の入力に帰還している。７はシャッターに
設けられた孔であり、閉および開に対応する位置に各２
個ずつ設けられている。８は発光器、９は受光器であり
、シャッター１′を挟んで２対を設ける。4 is a square wave signal generator, the output of which is input to the amplifier 3; Reference numeral 5 indicates a shutter opening/closing command signal, which is input to the square wave signal generator 4. 6 is a current detector, which uses a resistor in this example. Since a voltage proportional to the current of the DC motor 2 is obtained between both ends of this resistor, this voltage is fed back to the input of the amplifier 3. 7 is a hole provided in the shutter, and 2 holes are provided at the positions corresponding to the closed and open positions.
They are provided one by one. 8 is a light emitter, 9 is a light receiver, and two pairs are provided with a shutter 1' in between.
１０は演算増巾器であり、２個の受光器のうちの一方の
受光器の出力信号を、極性を逆にして増巾器３に加える
働きをする。Reference numeral 10 denotes an operational amplifier, which functions to reverse the polarity of the output signal from one of the two light receivers and apply it to the amplifier 3.
第２図は本発明の詳細な説明するための図である。本例
のように、シャッター１が４個の切欠き部を持つ場合に
は、閉から開、開から閉に至る回転角は４５度である。FIG. 2 is a diagram for explaining the present invention in detail. When the shutter 1 has four notches as in this example, the rotation angle from close to open and from open to close is 45 degrees.
この４５度を駆動する全時間ｔａの前半１／２を、直流
モーター２に許される最大の加速度で加速し、後半１／
２を同じく最大の加速度で減速すれば、最短時間での４
５度回転が行なわれる。この時の直流モーター２の速度
、電流と時間ｔの関係を、第２図（ａ）、（ｂ）に示す
。The first half of the total time ta for driving this 45 degrees is accelerated with the maximum acceleration allowed for the DC motor 2, and the second half is
If 2 is also decelerated at the maximum acceleration, 4 will be achieved in the shortest time.
A rotation of 5 degrees is performed. The relationship between the speed of the DC motor 2, the current, and the time t at this time is shown in FIGS. 2(a) and 2(b).
第２図（ａ）は、直流モーター２の速度が、前半の１／
２を直流モーター２に許される最大の加速度で加速して
Ｎ ｍ ａ ｘに達し、後半の１／２を同じく最大の加
速度で減速してＯにもどることを示している。Figure 2 (a) shows that the speed of the DC motor 2 is 1/1/2 of the first half.
2 is accelerated at the maximum acceleration allowed by the DC motor 2 to reach Nmax, and the latter half is decelerated at the same maximum acceleration to return to O.
第２図（ｂ）は、前半の１／２の期間、直流モーター２
に許される瞬時最大電流Ｉ ｍ＆Ｘを流し、後半の１／
２の期間、同じ＜Ｉ−ａ、ｌを逆向きに流さなければな
らないことを示す。Figure 2 (b) shows that during the first half period, the DC motor 2
Flow the instantaneous maximum current I m &
2, indicating that the same <I-a, l must flow in the opposite direction.
最短の駆動時間ｔａは、直流モーター２の仕様、シャッ
ター１の慣性能率等からあらかじめ正確に知り得る。方
形波信号発生器４は、シャッターの開閉指令信号５を受
けると、最初のｔａ ／２の期間に正、後のｔ＆／２の
期間に負、の方形波を発生するように構成する。この出
力波形を第２図（ｃ）に示す。The shortest driving time ta can be accurately known in advance from the specifications of the DC motor 2, the inertia rate of the shutter 1, and the like. The square wave signal generator 4 is configured to generate a positive square wave during the first period of ta/2 and a negative square wave during the subsequent period of t&/2 when receiving the shutter opening/closing command signal 5. This output waveform is shown in FIG. 2(c).
この方形波信号は、増巾器３、直流モーター２、電流検
出器６で構成される電流制御ループの指令値となるから
、直流モーター電流はこの方形波信号と相似になるよう
に制御され、結局シャッター１は所期の駆動が行なわれ
る。シャッター１に設けられた孔は終点位置に設けられ
ているので、回転の始点から終点付近までの途中の動作
には影響を与えない。This square wave signal becomes the command value for the current control loop composed of the amplifier 3, the DC motor 2, and the current detector 6, so the DC motor current is controlled to be similar to this square wave signal. In the end, the shutter 1 is driven as expected. Since the hole provided in the shutter 1 is provided at the end point position, it does not affect the operation during the rotation from the start point to near the end point.
第３図は、終点位置検出の原理を説明するための図であ
る。第３図（ａ）はシャッター１に設けた孔の１対をと
り出して示した図である。直線７′はシャッター１の停
止位置である。１対の孔は図のように停止位置を中心と
して位相をずらして設けられる。FIG. 3 is a diagram for explaining the principle of end point position detection. FIG. 3(a) is a diagram showing a pair of holes provided in the shutter 1. Straight line 7' is the stop position of shutter 1. As shown in the figure, the pair of holes are provided so as to be out of phase with each other about the stop position.
シャッター１を挟んで、発光器−受光器の組を２対設け
、番孔を通過する光の量が第３図（ｂ）のようになるよ
うにする、Ａは孔Ａを通過する光量、Ｂは孔Ｂを通過す
る光量である。つまり、閉または開の状態から円板がず
れると、一方の孔を通過する光はその量を増し、他方の
孔を通過する光はその量を減するように構成する。Two pairs of light emitters and light receivers are provided with the shutter 1 in between, and the amount of light passing through the hole is as shown in Fig. 3(b), where A is the amount of light passing through the hole A. B is the amount of light passing through hole B. In other words, when the disc deviates from the closed or open state, the amount of light passing through one hole increases and the amount of light passing through the other hole decreases.
各受光器は光量に比例した電圧を発生するようにし、一
方の受光器（図の例ではＢ側）の出力信号の極性を演算
増巾器１０により逆にして加算すると停止位置を中心に
して正負に振れる電圧信号が得られるので、これを増巾
器３に帰還する。これを第３図（ｃ）に示す。Each photoreceiver generates a voltage proportional to the amount of light, and when the polarity of the output signal of one photoreceiver (in the example shown in the figure, side B) is reversed by the operational amplifier 10 and summed, the output signal is centered around the stop position. Since a voltage signal that swings positive and negative is obtained, this is fed back to the amplifier 3. This is shown in FIG. 3(c).
シャッター１が停止位置に達すると、方形波信 １
号発生器４からの信号はＯになり、増巾器３への入力は
２個の受光器からの位置偏差信号のみとなり、この信号
によりシャッター１が正しい位置に切換え停止されるよ
うにその位置決め制御が行われる。When shutter 1 reaches the stop position, square wave signal 1
The signal from the signal generator 4 becomes O, and the only input to the amplifier 3 is the position deviation signal from the two receivers, which positions the shutter 1 so that it is switched to the correct position and stopped. Control takes place.
第４図（ａ）はシャッター１の回転角θと時間ｔの関係
を示す、これは第２図（ａ）を時間ｔで積分して得られ
る関数である。第４図（ｂ）はシャッター１を通過する
光量Ｓとθの関係で、（イ）は閉→開、（ロ）は開→閉
に対する図である。これは光束とこれを遮断するシャッ
ター１との幾何学的関係から得られる関数である。FIG. 4(a) shows the relationship between the rotation angle θ of the shutter 1 and time t. This is a function obtained by integrating FIG. 2(a) over time t. FIG. 4(b) shows the relationship between the amount of light S passing through the shutter 1 and θ, with (a) showing the relationship from closed to open, and (b) showing the relationship from open to closed. This is a function obtained from the geometrical relationship between the light flux and the shutter 1 that blocks it.
第４図（ａ）、（ｂ）は図示のようにｔ１→θ、→Ｓ１
の順に読み取ることにより各時刻ｔ１における光量Ｓｌ
が求められる。第４図（ｃ）は、このようにして求めた
、シャッター１を開き始めてから閉じるまでのＳとｔの
関係を示す図である。FIGS. 4(a) and (b) show t1→θ, →S1 as shown in the figure.
By reading the light amount Sl at each time t1 in the order of
is required. FIG. 4(c) is a diagram showing the relationship between S and t from the time when the shutter 1 starts to be opened until it is closed, obtained in this manner.
第４図（ｃ）の（イ）、（ロ）はシャッター１を駆動中
の期間であり、（イ）は閉→開、（ロ）は開→閉に対応
する。（ハ）は開状態で停止している期間であり、露光
時間の長さはこの期間の長さをｔａを加減することによ
り設定される。(a) and (b) in FIG. 4(c) are the periods during which the shutter 1 is being driven, (a) corresponds to close → open, and (b) corresponds to open → close. (C) is a period in which the lens is stopped in the open state, and the length of the exposure time is set by adjusting the length of this period by adding or subtracting ta.
露光時間は、光量の立上りで５０％を切る時刻から、立
下りで５０％で切る時刻までの時間で定義されるが、図
から明らかなようにｔｚ＋ｔｚより短かくすることはで
きない、従って、シャッターを高速化することはｔｘ
＋ｔ！を小さくすることであり、これは閉→開、開→閉
に必要な時間を小さくすることによって実現される。Exposure time is defined as the time from the time when the amount of light falls below 50% to the time when it cuts off to 50% at the fall, but as is clear from the figure, it cannot be shorter than tz+tz, so the shutter To speed up the tx
+t! This is achieved by reducing the time required for closing to opening and opening to closing.
なお、本発明の実施例によれば、速度計発電機やパルス
エンコーダなど、光路の障害となる器具や部品を不要と
するコンパクトなシャッター制御装置が得られる。Note that, according to the embodiments of the present invention, a compact shutter control device can be obtained that does not require instruments or parts that obstruct the optical path, such as a speedometer generator or a pulse encoder.
以上の説明から明らかなように、本発明によれば、モー
ターの能力を最大限に使用してシャッター駆動の高速化
を図ることができる。As is clear from the above description, according to the present invention, it is possible to maximize the capacity of the motor and increase the speed of shutter drive.
第１図は本発明の一実施例を示すシャッター制御装置の
概念図、第２図は本発明の実施例の動作原理の説明図、
第３図は終点位置検出の原理説明図、第４図は回転角度
θ、シャッターを通過する光量Ｓと時間ｔの関係を示す
図である。
１，１′・・・シャッター、２・・・直流モーター、３
・・・増巾器、４・・・方形波信号発生器、５・・・シ
ャッター開閉指令信号、６・・・電流検出器、７・・・
停止位置検出用孔、７′・・・停止位置、８・・・発光
器、９・・・受光器、１０・・・演算増幅器、１１・・
・光芒の断面。FIG. 1 is a conceptual diagram of a shutter control device showing an embodiment of the present invention, FIG. 2 is an explanatory diagram of the operating principle of the embodiment of the present invention,
FIG. 3 is a diagram explaining the principle of detecting the end point position, and FIG. 4 is a diagram showing the relationship between the rotation angle θ, the amount of light S passing through the shutter, and the time t. 1, 1'...Shutter, 2...DC motor, 3
... Amplifier, 4... Square wave signal generator, 5... Shutter opening/closing command signal, 6... Current detector, 7...
Stop position detection hole, 7'... Stop position, 8... Emitter, 9... Light receiver, 10... Operational amplifier, 11...
・Cross section of the beam of light.
Claims (1)
ーと、前記光通過部および光遮断部を選択的に光束位置
に切換えるように前記シャッターを回転するモーターと
、前記光束位置に前記光通過部および光遮断部のうちの
一方が切換えられている状態から他方が切換えられるま
での期間の前半部分においては前記モーターを等加速度
的に増速し、後半部分においては前記モーターを等加速
度的に減速するように前記モーターの回転を制御する手
段とを備えているシャッター制御装置。 ２、円周に沿つて光通過部と光遮断部を設けたシャッタ
ーと、前記光通過部および光遮断部を選択的に光束位置
に切換えるように前記シャッターを回転するモーターと
、前記光束位置に前記光通過部および光遮断部のうちの
一方が切換えられている状態から他方が切換えられるま
での期間の前半部分においては前記モーターを等加速度
的に増速し、後半部分においては前記モーターを等加速
度的に減速するように前記モーターの回転を制御する手
段と、前記シャッターの切換え停止位置ずれを補正する
手段とを備え、該補正手段は前記光通過部および光遮断
部の各々が前記光束位置に正しく切換え停止されたとき
は互いに実質的に等しい第１および第２の光信号を発生
するが、前記光束位置からずれたときは前記第１の光信
号は増大し、前記第２の光信号は減少するように構成さ
れているとともに、前記第１および第２の光信号にもと
づいて前記光通過部および光遮断部の各々の前記光束位
置に対する切換え停止位置制御を行うように構成されて
いるシャッター制御装置。[Scope of Claims] 1. A shutter provided with a light passing part and a light blocking part along the circumference, and a motor rotating the shutter so as to selectively switch the light passing part and the light blocking part to light flux positions. Then, during the first half of the period from when one of the light passing section and the light blocking section is switched to the light flux position until the other is switched, the motor is accelerated at a uniform rate, and during the second half. In the shutter control device, the shutter control device includes means for controlling the rotation of the motor so as to decelerate the motor at a constant acceleration. 2. A shutter provided with a light passing part and a light blocking part along the circumference; a motor rotating the shutter so as to selectively switch the light passing part and the light blocking part to the light flux position; During the first half of the period from when one of the light passing section and the light blocking section is switched to when the other is switched, the motor is accelerated at a constant rate, and during the second half, the motor is accelerated at a constant rate. The correcting means includes means for controlling rotation of the motor so as to decelerate in an accelerated manner, and means for correcting a shift in the switching stop position of the shutter, and the correcting means is configured such that each of the light passing section and the light blocking section is adjusted to the position of the light flux. When properly switched and stopped, the first and second optical signals are generated that are substantially equal to each other, but when the light beam deviates from the position, the first optical signal increases and the second optical signal increases. is configured to decrease, and is configured to perform switching stop position control for the light flux position of each of the light passing section and the light blocking section based on the first and second optical signals. Shutter control device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60169854A JPS6231834A (en) | 1985-08-02 | 1985-08-02 | Shutter control device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60169854A JPS6231834A (en) | 1985-08-02 | 1985-08-02 | Shutter control device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6231834A true JPS6231834A (en) | 1987-02-10 |
Family
ID=15894168
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60169854A Pending JPS6231834A (en) | 1985-08-02 | 1985-08-02 | Shutter control device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6231834A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6445176A (en) * | 1987-08-14 | 1989-02-17 | Hitachi Ltd | Manufacture of solar cell element |
| JPH04139769A (en) * | 1990-10-01 | 1992-05-13 | Hitachi Ltd | Manufacture of corrugated solar battery |
| JP2004240097A (en) * | 2003-02-05 | 2004-08-26 | Dainippon Printing Co Ltd | Exposure method and aligner |
| JP2008219000A (en) * | 2007-02-26 | 2008-09-18 | Asml Netherlands Bv | Lithographic apparatus and method |
| JP2015149450A (en) * | 2014-02-07 | 2015-08-20 | キヤノン株式会社 | Exposure device and method of manufacturing article |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS537328A (en) * | 1976-07-09 | 1978-01-23 | Yashica Co Ltd | Method and device for controlling rotary shutter |
| JPS5595809A (en) * | 1979-01-16 | 1980-07-21 | Noriaki Fujimura | Optical axis detector |
-
1985
- 1985-08-02 JP JP60169854A patent/JPS6231834A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS537328A (en) * | 1976-07-09 | 1978-01-23 | Yashica Co Ltd | Method and device for controlling rotary shutter |
| JPS5595809A (en) * | 1979-01-16 | 1980-07-21 | Noriaki Fujimura | Optical axis detector |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6445176A (en) * | 1987-08-14 | 1989-02-17 | Hitachi Ltd | Manufacture of solar cell element |
| JPH04139769A (en) * | 1990-10-01 | 1992-05-13 | Hitachi Ltd | Manufacture of corrugated solar battery |
| JP2004240097A (en) * | 2003-02-05 | 2004-08-26 | Dainippon Printing Co Ltd | Exposure method and aligner |
| JP2008219000A (en) * | 2007-02-26 | 2008-09-18 | Asml Netherlands Bv | Lithographic apparatus and method |
| JP2015149450A (en) * | 2014-02-07 | 2015-08-20 | キヤノン株式会社 | Exposure device and method of manufacturing article |
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