JPH0917718A - Aligner and device, and manufacturing method using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aligner for inexpensively manufacturing precision device. SOLUTION: An aligner has a transmission liquid crystal display 2 for displaying a circuit pattern, a wafer stage 9 for relatively moving a wafer 4 to be mounted and the display 2, a projection image-forming optical system 3 for projecting a pattern displayed on the display 2 on the wafer 4 to form an image, and a display control device 6 for changing the pattern being displayed on the display 2 in synchronization with the relative move between the display 2 and the wafer 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus and a device production method used when producing microdevices such as semiconductor devices.

[0002]

2. Description of the Related Art In a semiconductor exposure apparatus, which is the key to the manufacture of semiconductor integrated circuits, a reticle having a fine circuit pattern formed on a glass substrate is prepared and illuminated by an illumination optical system. The pattern is exposed and transferred by reducing and projecting it on the resist-coated wafer. Since many circuit patterns are superposed on the same wafer when manufacturing an integrated circuit, after exposing and transferring one pattern, a resist is applied to the wafer again after a predetermined process, and another reticle is used again. And layer it.

However, the reticle is expensive and 1
The number of reticles required to manufacture one integrated circuit is costly. Therefore, when mass-producing the same integrated circuit, it is still difficult to manufacture a small number of special integrated circuits and devices at low cost, and there is a problem that a small circuit design cannot be changed. In addition, the reticle holding accuracy must be highly managed every time the reticle is replaced, which requires a sophisticated alignment mechanism and lowers the throughput. Further, there is a problem that minute dust or dust is likely to be generated when the reticle is replaced.

[0004]

In order to solve this problem, a mask pattern is displayed and formed on a two-dimensional display (transmissive liquid crystal display) instead of the reticle, and this is irradiated with light to transmit transmitted light. The idea of reduction transfer to a wafer has been proposed (Japanese Patent Laid-Open No. 50-159677, Japanese Patent Laid-Open No. 6-232).
No. 024, No. 64-5017, No. 2-307, No. 2-129710, No. 2-209729, No. 4-23314, No. 3-201423 Issue Bulletin).

However, it is not easy to produce a liquid crystal display capable of displaying a fine two-dimensional pattern such as an integrated circuit, and it is difficult to put it into practical use especially in the situation where the circuit pattern is increasing in area. Accompanied by sex.

The present invention has been made in view of the above circumstances,
An object of the present invention is to provide an exposure apparatus and a device production method capable of accurately and inexpensively performing exposure transfer even on a pattern of a large area.

[0007]

In order to achieve the above object, an exposure apparatus of the present invention comprises a display means for displaying a pattern, and a stage for mounting a wafer and moving the wafer and the display means relative to each other. And projection means for projecting the pattern displayed on the display means onto the wafer, and means for changing the pattern displayed on the display means in synchronization with the relative movement of the display means and the wafer. It is a feature.

[0008]

【Example】

<Embodiment 1> FIG. 1 shows the construction of the first embodiment of the present invention.

In the figure, 1 is a light source unit including a light source such as a mercury lamp and an excimer laser and an illuminating lens, 2 is a one-dimensional liquid crystal display for displaying a circuit diagram to be transferred and device figures, and 3 is a liquid crystal display. A projection imaging lens for projecting and forming an image on a wafer, 4 a wafer onto which a circuit pattern and the like are transferred, 5 a controller for controlling the entire exposure apparatus (having a memory for storing data of a plurality of types of circuit patterns), 6 Is a display control device for controlling the display contents of the liquid crystal display 2, 7 is a wafer transfer system, 9 is a wafer stage, and 10 is a wafer stage control system.

First, the wafer 4 to which the resist is applied is transferred to the wafer stage 9 by the wafer transfer system 7, and the wafer 4 is positioned at the exposure position at the image plane position of the projection imaging lens 3 on the wafer stage 9. Then the controller 5
In response to the instruction, the one-dimensional liquid crystal display 2 is controlled so that the display control device 6 displays the circuit pattern to be transferred, and a part of the entire circuit pattern is displayed. Here, the controller 5 sends an instruction to the light source unit 1 to illuminate the display 2 with light. A part of the circuit diagram displayed on the liquid crystal display 2 is projected and imaged on the wafer by the projection imaging lens 3, and the circuit pattern 8 is exposed and transferred in a slit shape on the wafer. At this time, a control signal is simultaneously sent from the controller 5 to the wafer stage control system 10 and the display control device 6,
The wafer stage is controlled so that the wafer moves at a constant speed. On the other hand, the display control device 6 continuously switches the display contents of the display 2 in synchronization with the movement of the wafer stage so that the circuit pattern on the wafer is transferred as a desired circuit diagram.

FIG. 2 is a view showing the exposed portion of the wafer to be transferred and the display contents on the display. The left side of the figure is a circuit pattern to be transferred, the right side is an exposure pattern on the wafer, 21 is the whole pattern to be transferred, 22 is the part where the pattern is being displayed, 23 is the displayed part, and 24 is the circuit pattern transferred A region to be exposed, a region 25 being exposed, a region exposed 26, and a wafer traveling direction 27.

First, at the start of exposure, the wafer is arranged so that the exposure slit is positioned at one end of the desired exposure area of the wafer as indicated by A in the figure, and one display device displays the corresponding one end of the circuit pattern to be transferred. To do. Although the display has a little width in the figure, it is assumed that the actual display device has only one pixel width. The wafer is moved in the direction of arrow 27 while the light source is irradiating. The display contents are sequentially switched to B, C, D and E as the wafer advances. When the exposure slit reaches the end of the desired exposure area of the wafer at E, the irradiation of the light source is stopped. When all the circuits are displayed in this way, one exposure area on the wafer is completed. Overprinting of the second and subsequent patterns is performed in the same procedure.

The amount of exposure can be controlled by adjusting the intensity of the light source (that is, the intensity of irradiation light). Or wafer movement speed and display switching speed (ie irradiation time)
May be adjusted. That is, if the exposure amount is increased, the moving speed of the wafer is decreased and the display time for one line is increased at the same time.

In the above embodiment, an example of a linear slit is shown, but a slit display having another shape such as an arc shape and having a one-dimensional spread may be used.

In this embodiment, the projection imaging lens is used as the projection imaging optical system. However, a projection imaging optical system such as a refraction system, a reflection system, a diffractive system, or a combination thereof is used. It can also be used.

Further, although the liquid crystal display is used as the transmissive display in this embodiment, the present invention is not limited to this, and the CR display is used.
A self-luminous display such as a T display, or a reflective display using a microdeformable mirror device can also be used. A self-luminous display does not require a light source for illumination.

<Second Embodiment> FIG. 3 shows the structure of a second embodiment of the present invention.

In the figure, 31 is a light source section including a light source such as a mercury lamp or an excimer laser and an illuminating lens, and 32 is a two-dimensional transmissive display for displaying a circuit diagram to be transferred or a device figure. Let's use a rectangular display. Reference numeral 33 is a projection image forming lens for projecting and forming an image of a transmissive display on a wafer, 34 is a wafer for transferring a circuit, 35 is a controller for controlling the main exposure apparatus, and 36 is a display content of the transmissive display 32. A display control device, a wafer transfer system 37, a wafer stage 39, a wafer stage control system 40, and a stage position detection system 41.

The purpose of this embodiment is to increase the exposure area and the exposure amount. First, the wafer transfer system 37
The wafer 34 to which the resist is applied is placed on the wafer stage 39.
Then, the wafer 34 is positioned at the exposure position at the image plane position of the projection image forming lens 33 by the wafer stage 39. According to an instruction from the controller 35, the display control device 36 controls the two-dimensional transmissive display 32 so as to display a circuit diagram to be transferred, and displays a part of the entire circuit pattern. At the same time, the controller sends an instruction to the light source unit 31 to illuminate the display 32 with light. A part of the circuit diagram displayed on the transmissive display 32 is projected and imaged on the wafer by the projection imaging lens 33 to form the circuit pattern 3
8 is exposed and transferred to a rectangle. At this time, the controller 35
A control signal is simultaneously sent from the wafer stage control system 40 and the display controller 36 to control the wafer stage so that the wafer moves at a constant constant speed. On the other hand, the display control device 3
At 6, the display contents of the display 32 are continuously switched so that the circuit pattern on the wafer is transferred as a desired circuit diagram.

At this time, in order to prevent the display image projected and formed on the wafer from moving with respect to the wafer, when the moving speed of the contents of the display is V, the moving speed of the wafer is v = MV. Have to control.
On the other hand, at this time, the position of the wafer is detected by the stage position detection system 37, and the position information is returned to the display controller 36 so that the display corresponding to the position of the wafer is made. This is effective in preventing the transferred pattern from being distorted when the movement of the stage cannot be maintained at a constant speed due to various factors.

FIG. 4 is a view showing the exposed portion of the wafer to be transferred and the display contents on the display. The left side of the figure is a conceptual view of the transferred circuit pattern and display, the right side is the exposure pattern on the wafer, and the center is the actual display content. 51 is the entire pattern to be transferred, 52 is the portion of the pattern being displayed, 5
3 is a displayed portion, 54 is an area to which a circuit pattern is transferred, 55 is an area being exposed, 56 is an exposed area, and 57 is a wafer traveling direction.

The irradiation of the light source starts from A, and the display starts as the transfer area 54 of the wafer enters the exposure area 55.
As the wafer moves to the left, the displayed contents are sequentially output from the right. Since the image is actually inverted by the projection imaging lens, it is fed out from the left on the display device as shown in the center column. Although not shown in the figure from the state A to the state B, the wafer is actually at the projection image forming position and the display 1
The display switches each time the pixel moves. In this way, since each point on the transfer pattern is exposed on the wafer while the point moves from one end of the display to the other end, a long exposure time can be secured. Further, since the pattern can be transferred by the amount that can be scanned at the wafer exposure position, the exposure area can be expanded.

A stage speed detection system may be provided instead of the stage position detection system 311. At this time, if the speed of the wafer is v, the magnification of the projection imaging lens is set to M, and the contents displayed on the display are switched so as to move at a speed of v / M. It becomes a relationship that does not move,
The pattern is transferred without distortion. Further, it is also possible to correct the rotation of the wafer by detecting the rotation information of the wafer and returning the rotation information to the display device.

In this embodiment, the projection image forming lens is used as the projection image forming optical system. However, a projection image forming optical system such as a refraction system, a reflection system, a diffractive system, or a combination thereof is used. It can also be used.

Further, although the liquid crystal display is used as the transmissive display in this embodiment, the present invention is not limited to this, and the CR display is used.
A self-luminous display such as a T display, or a reflective display using a microdeformable mirror device can also be used. A self-luminous display does not require a light source for illumination.

<Embodiment 3> Next, an embodiment of a device manufacturing method using the above-described exposure apparatus will be described.

FIG. 5 shows a flow of manufacturing minute devices (semiconductor chips such as IC and LSI, liquid crystal panels, CCDs, thin film magnetic heads, micromachines, etc.). Step 1
In (circuit design), a circuit of a semiconductor device is designed.
Step 2 is a process for making a mask on the basis of the circuit pattern design. On the other hand, in step 3 (wafer manufacturing), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is called a pre-process,
An actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). including. In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 6 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. Step 15
In (resist processing), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus to print and expose the circuit pattern of the mask onto the wafer. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), the resist that is no longer needed after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the manufacturing method of this embodiment, it is possible to manufacture a highly integrated semiconductor device, which has been conventionally difficult to manufacture, at low cost.

[0030]

According to the present invention described in claims 1 to 8,
To transfer exposure while changing the display pattern in synchronization with movement. The exposure area can be expanded while maintaining high accuracy.

According to the present invention described in claim 9, by detecting the information on the relative movement and feeding back the information to the display control based on the information, it is possible to compensate the distortion and the rotation error of the transfer pattern.

According to the present invention of claim 10, a highly accurate device can be produced at low cost.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a diagram showing an operation of the first embodiment.

FIG. 3 is a diagram showing a configuration of a second embodiment of the present invention.

FIG. 4 is a diagram showing an operation of the second embodiment.

FIG. 5 is a diagram showing a production flow of a semiconductor device.

FIG. 6 is a diagram showing a detailed flow of a wafer process.

[Explanation of symbols]

 1, 31 Light source 2 1-dimensional display 32 2-dimensional display 3, 33 Projection imaging lens 4, 34 Wafer 5, 35 Controller 6, 36 Display control device 7, 37 Wafer transfer system 8, 38 Exposure area 9, 39 Wafer stage 10 , 40 Stage control system 11, 41 Stage position detection system

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Minoru Yoshii 53, Imaiuemachi, Nakahara-ku, Kawasaki-shi, Kanagawa Canon Inc. Kosugi Plant

Claims (10)

[Claims] 1. A display means for displaying a pattern, a stage for mounting a wafer and moving the wafer and the display means relative to each other, and a projection means for projecting the pattern displayed on the display means onto the wafer. An exposure apparatus comprising: a means for changing a pattern displayed on the display means in synchronization with a relative movement of the display means and a wafer. 2. The exposure apparatus according to claim 1, further comprising an illumination unit that illuminates the display unit. 3. The exposure apparatus according to claim 1, wherein a reflective display is used as the display means. 4. The exposure apparatus according to claim 1, wherein a self-luminous display is used as the display means. 5. The exposure apparatus according to claim 1, wherein a transmissive display is used as the display means. 6. The exposure apparatus according to claim 1, wherein a liquid crystal display is used as the display means. 7. The exposure apparatus according to claim 1, wherein a micro-deformable mirror device is used as the display means. 8. The exposure apparatus according to claim 7, wherein a CRT display is used as the display means. 9. The display device according to claim 1, further comprising a detection unit that detects information about the relative movement, and controls the display of the display unit based on the detection of the detection unit. Exposure equipment. 10. A device production method, which produces a device using the exposure apparatus according to claim 1. Description: