JP2541279B2 - Semiconductor manufacturing equipment - Google Patents

Description

The present invention relates to a semiconductor manufacturing apparatus that exposes and transfers a pattern on a mask onto a wafer by using synchrotron radiation (SR). A mask stage that holds a mask and can move up and down, with the aim of providing a semiconductor manufacturing apparatus that is downsized.
A wafer stage that holds the wafer and can move in the XY directions,
At the time of exposure and transfer, the wafer stage is moved with the mask stage stopped, positioning between the mask and the wafer is performed, and then the wafer stage is provided with a connecting means for connecting the mask stage. The mask stage of the means is moved up and down and exposed and transferred by irradiation with synchrotron radiation.

[Industrial applications]

The present invention relates to a semiconductor manufacturing apparatus for exposing and transferring a pattern on a mask onto a wafer by using synchrotron radiation (SR).

There is a semiconductor manufacturing apparatus in which a high-density integrated circuit pattern on a mask is exposed and transferred onto a wafer by X-ray. The transfer principle of the device is that an X-ray generated by applying an electron beam to a metal target irradiates a mask closely contacted or brought close to the resist-coated wafer surface, and the mask pattern is transmitted by the X-ray transmitted through the mask. It is baked on the resist.

In this normal X-ray transfer, since the radiation source is a divergent source, the X-rays reaching the sample decrease in proportion to the distance. To compensate for this, a powerful X-ray source must be used. One way is to use a focused source such as synchrotron radiation (SR).

[Conventional technology]

X-ray lithography of semiconductors by synchrotron radiation (SR) has attracted attention as a next-generation submicron pattern transfer technology. In this exposure apparatus (stepper) for manufacturing a synchrotron radiation light semiconductor, the SR light 1 has an elongated shape as shown in FIG. That is, the electrons are accelerated by an accelerator (not shown) and enter the storage ring 2. The electrons are arranged in the storage ring 2 and the orbit is bent by the bending electromagnet 3, and the electrons orbit the vacuum storage ring (pipe) 2. This deflection electromagnet 3
Radiation light is emitted tangentially from the part where the electron orbit is bent at. An SR filter is obtained by inserting a filter (not shown) into this radiant light and cutting off all but the X-rays.

The SR light 1 can cover the area exposed at one time with the stepper in the horizontal direction, but not in the vertical direction.
The situation is as shown in the figure. Reference numeral 4 indicates a one-shot exposure area.

Therefore, in the stepper, it is necessary to move the mask in the vertical direction while keeping the mask and the wafer superposed on each other (hereinafter referred to as scanning) to expose the entire exposure area to the SR light 1. Further, since the storage ring 2 has a large diameter of 5 to 10 m and is placed horizontally, the SR light 1 is emitted in the horizontal direction, so that it is necessary to stand the mask and the wafer.

In consideration of such a situation, conventionally, a method of performing scanning by raising a normal stepper (see XY stage 5 in FIG. 6) and moving the entire apparatus A up and down as shown in FIG. 7 is considered. It was being done. The mechanism for driving the entire apparatus up and down connects the steel band 8 to the apparatus and drives the steel band 8 by the motor 6. 7 is a weight for balancing. Incidentally, FIG. 8 shows the details of the inside of the entire apparatus A, in which the wafer 9 is chucked by a wafer.
At 12, the XY stage 5 is held, and the XY stage 5 is fixed to the XY stage base 13. Further, the mask 10 is fixed to the mask stage 11 by the mask chuck 15, and the mask stage
11 is held on the XY stage base 13 via the structure 14.

As another method of irradiating the entire exposure area, although not shown, for example, a method of reflecting X-rays using a mirror and moving the mirror may be used.

[Problems to be Solved by the Invention]

However, in the former method of moving the entire apparatus up and down (vertical direction), it is necessary to move up to the base of the XY stage 5 on which the wafer 9 is placed (XY stage base 13 in FIG. 8). However, the base (XY stage base 13) of the device for performing ultra-precision alignment is apt to become heavy because it is necessary to prevent vibration. Therefore, there is a drawback that the vertical drive mechanism for scanning becomes large-scale.

The latter method of reflecting X-rays using a mirror is
At this stage, there is no mirror that efficiently reflects X-rays,
There is also a problem that the wavelength of reflected light changes when the reflection angle changes.

Therefore, an object of the present invention is to provide a semiconductor manufacturing apparatus in which it is easy to drive the entire irradiation of the exposure area with SR light and the apparatus is downsized.

[Means for solving the problem]

As shown in FIG. 1, the above problems are caused by a mask stage 11 that holds a mask 10 and can move up and down, and a wafer stage that holds a wafer 9 and can move in the XY directions.
16, and at the time of exposure transfer, the wafer stage 16 is moved with the mask stage 11 stopped to perform relative positioning between the mask 10 and the wafer 9, and then the wafer stage 16 and the mask stage 11 are connected to each other. And a means for moving the mask stage 11 in a connected state by the connecting means up and down and exposing and transferring by irradiation of synchrotron radiation light.

[Action]

That is, when scanning the mask 10 and the wafer 9 with SR light,
Immediately below the mask 10 positioned in place (horizontal in the figure)
After the exposure area of the wafer 9 is positioned on the mask 9, the mask stage 11 is vertically moved by the vertical axis guide 19 with the mask 10 and the wafer 9 connected to each other. Therefore, the drive of the scan only moves the mask stage 11 up and down, and the whole device (the XY that performs ultra-precision alignment
Since it is not necessary to move the stage base 13), the number of driven members is small, the weight is light, and the driving is easy. Therefore, the size of the device can be reduced.

〔Example〕

FIG. 1 is a diagram for explaining an embodiment of the present invention. In addition, the same reference numerals denote the same objects throughout the drawings.

In FIG. 1, 1 is SR light, 5 is an XY stage, 9 is a wafer, 10 is a mask, 11 is a mask stage, 13 is an XY stage base, 16 is a wafer stage, and 19 is a vertical axis guide.

At the time of exposure transfer, the mask stage 11 is stopped,
The wafer stage 16 is moved to position the mask 10 and the wafer 9. After the positioning is completed, the wafer stage 16 is connected to the mask stage 11 (an example of this method will be described later). By driving the mask stage 11 after connection,
The scan is done. At this time, the wafer stage 16
Move the Y-axis guide in the figure.

Regarding the connection method, (1) Connection by servo The laser length measuring device 20 is arranged so that the relative distance between the mask stage 11 and the wafer stage 16 in FIG. 1 can be measured, and the wafer stage 16 is controlled by the measured value. It Although not shown, the mask stage 11 is driven by, for example, a motor and a ball screw, and is controlled by a rotary encoder. Figure 2 is the block diagram, and the exposure is the mask stage.
The 11 target positions are the initial positions. Then, the target relative position of the wafer stage 16 is given to the servo circuit I to move the exposure area of the wafer below the mask (horizontally in the figure). After the relative positioning is completed, the target speed of the mask stage 11 is given to the servo circuit II to perform scanning. At this time, since the target relative position of the wafer stage 16 is controlled, the mask and the wafer are connected and move.

(2) Mechanical connection For example, as shown in FIG. 3, suction pads 17 are provided at four corners of the wafer stage 16, and suction is applied to the mask stage 11 by vacuum suction, electromagnetic suction, or the like, and the mask stage 11 and the wafer stage are connected. The 16 is mechanically connected and moves up and down for scanning as a unit. 19 is a vertical axis guide.

As described above, the drive system for scanning only connects the wafer stage 16 and the mask stage 11 and moves the mask stage 11 up and down after the relative positioning of the mask and the wafer, and the weight of the conventional system is reduced. Since the entire large device (XY stage base 13) is not moved up and down, the driving becomes easy and the entire device is downsized.

〔The invention's effect〕

As described above, according to the present invention, the guide and drive system for scanning may be configured to move the mask up and down mainly, and it is not necessary to drive the entire apparatus up and down as in the conventional case. Is easy and the entire device can be downsized.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an embodiment of the present invention, FIG. 2 is a block diagram of connection by servo of the present invention, FIG. 3 is a configuration diagram of mechanical connection of the present invention, and FIG. 4 is synchrotron radiation light. FIG. 5 is a diagram showing the shape of (SR), FIG. 5 is a diagram showing the relationship between the exposure area and SR light, FIG. 6 is a diagram showing the XY stage, FIG. 7 is a diagram for explaining the vertical drive of the entire apparatus, and FIG. It is a figure which shows what was moved at the time of the conventional scan. In the figure, 1 is SR light, 5 is an XY stage, 9 is a wafer, 10 is a mask, 11 is a mask stage, 13 is an XY stage base, 16 is a wafer stage, and 19 is a vertical axis guide. Reference numeral 20 is a mask stage guide, and 21 is a wafer stage guide.

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Toru Kamata 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Limited

Claims (3)

(57) [Claims] 1. A mask stage (11) which holds a mask (10) and can move up and down; a wafer stage (16) which holds a wafer (9) and can move in the XY directions; After the mask stage (11) is stopped, the wafer stage (16) is moved to position the mask (20) and the wafer (9), and then the wafer stage (16) and the mask stage (11) are connected. A semiconductor manufacturing apparatus, comprising: a mask stage (11) vertically moved by the connecting means, and performing an exposure operation by irradiating synchrotron radiation light. 2. The mask stage (1)
2. The relative distance between 1) and the wafer stage (16) is measured by a laser length-measuring device (20 '), and the wafer stage (11) is controlled according to the measured value. Semiconductor manufacturing equipment. 3. The wafer stage (1)
6. The semiconductor manufacturing apparatus according to claim 1, wherein a suction pad is provided on 6) and the mask stage (11) is mechanically connected.