JP2000252193A - Aligner, exposure method and manufacture of device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent operation errors, when an exposure operation is carried out using an original plate with a shading band. SOLUTION: In an aligner, where a region of the original plate 234 other than an exposure region is shaded with a masking blade 223 when a pattern on an original plate 224 is transferred onto a substrate 226, when an exposure operation is carried out using an original plate with a shading band, control means 202, 203, and 210 are provided to control the position of the masking blade, so as to make the masking blade located at the widthwise center of the shading band, based on the position of the masking blade set conforming to an exposure region and the width of the shading band. The width of the shading band is obtained in a manner where the substrate 226 is moved by a stage 227, and light that passes through the substrate 226 is observed with an optical sensor 228.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus, an exposure method, and a device manufacturing method for manufacturing a device such as a semiconductor element or a liquid crystal element, and more particularly, to covering an outside of an exposure range of an original pattern required for exposure processing. The present invention relates to a method for controlling a light shielding plate.

[0002]

2. Description of the Related Art Generally, when an exposure process is performed, the range of light is limited by a light-shielding plate called a masking blade so that exposure light does not reach an unnecessary area of a reticle or mask which is an original circuit diagram. However, when the exposure process is performed by controlling the exposure area with the masking blade, the accuracy of depiction of the semiconductor element pattern as an image is reduced in the vicinity where light is shielded by the masking blade. Therefore, a light-shielding band is provided on the outer periphery of the pattern of the reticle, and the masking blade is widened in the opening direction by の of the light-shielding band width, thereby preventing a decrease in drawing accuracy.

[0003]

However, when the above operation is performed on a reticle having a light-shielding band, the opening width of the masking blade and the element spacing on the wafer are different. For this reason, the opening width of the masking blade must be increased by half the width of the light-shielding band of the reticle, and an operational error is likely to occur.

In addition, if an offset of the apparatus is set in advance so that a half of the width of the reticle light-shielding band is added to the masking blade, an error occurs when a reticle having no light-shielding band or a reticle having a different light-shielding band width is used. Easy to occur.

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, it is an object of the present invention to prevent the above-mentioned operational mistakes when performing exposure using an original plate having a light-shielding band in an exposure apparatus and a device manufacturing method. Is to do.

[0006]

In order to attain this object, an exposure apparatus according to the present invention comprises an exposure apparatus for exposing a pattern other than an exposure area with a masking blade when exposing a pattern of an original onto a substrate. When performing exposure using an original plate having a band, based on the position of the masking blade set in accordance with the exposure area and the width of the light-shielding band, the position of the masking blade is adjusted to the width of the light-shielding band. It is characterized by comprising means for controlling the position of the masking blade so as to be located at the center. Here, the position of the masking blade set in accordance with the exposure area is, for example, the position of the masking blade set by performing the setting of the masking blade area so as to be equal to the element interval during job creation. Say.

Further, according to the exposure method of the present invention, when exposing a pattern of an original plate onto a substrate, an area other than an exposure area is shielded by a masking blade, the exposure is performed using an original plate having a light-shielding band. In this case, using the exposure apparatus of the present invention, the control unit controls the position of the masking blade based on the position of the masking blade set in accordance with the exposure area and the width of the light-shielding band. The position of the masking blade is controlled so as to be located at the center of the width of the masking blade.

Further, a device manufacturing method of the present invention is characterized in that a device is manufactured by performing exposure by this exposure method.

According to this, the masking blade is controlled to be located at the center of the width of the light-shielding band on the basis of the position of the masking blade and the width of the light-shielding band which are set in accordance with the exposure area. Therefore, even when an original plate having a light-shielding band is used, the set value of the interval between the masking blades and the interval between the elements may be kept the same, so that operational errors are reduced.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment of the present invention, when performing exposure using a master plate having a light-shielding band, the control means acquires the width of the light-shielding band. For example, the width of the light-shielding band is obtained by moving the substrate and observing light transmitted through the substrate. According to this, since it is not necessary to input the light-shielding band width as the offset of the apparatus, it is not necessary to narrow the input range of the offset or to narrow the minimum setting interval of the masking blade.

Further, the apparatus has a means for displaying a shot layout, and this means, when exposure using an original plate having a light-shielding band is performed, opens an opening by a masking blade located under the control of the control means. Display it on the layout.

[0012]

(Embodiment 1) FIG. 1 is a configuration diagram of a conductor element exposure apparatus according to a first embodiment of the present invention. In the figure,
Reference numeral 101 denotes a laser light source that emits pulsed laser light, for example, in which KrF or ArF is sealed. Reference numeral 102 denotes an illumination system for shaping a laser beam emitted from the excimer laser light source 101 into a desired beam shape, and irradiating the light beam with uniform light distribution characteristics. The beam shaping optical system, an optical integrator such as a fly-eye lens, Collimeter lens,
It is composed of a mirror and the like. M is a mask or a reticle on which an integrated circuit pattern is formed, and 103 is a projection optical system, W is a wafer, and W is a wafer, and the integrated circuit pattern formed on the mask M is a masking blade 109. Is the projection optical system 3
Are projected and exposed on the wafer W through the.

Reference numeral 104 denotes a mirror, 105 denotes a sensor,
A part of the light beam irradiated by the illumination system 102 is made incident on the photoelectric conversion surface of the sensor 105 by the mirror 104. 10
Reference numeral 6 denotes a light amount integration circuit that integrates the amount of pulse light incident on the sensor 105.

Reference numeral 107 denotes a CPU, which is an excimer laser 1
Each time 01 emits light, a 1-pulse signal is input from the light quantity integration circuit 106. The CPU 107 controls the laser control unit 10
A control command such as a light emission timing is issued to the excimer laser 101 via 8. Further, the masking blade control unit 110 controls the masking blade 109 in accordance with a control command such as a position command of the CPU 107 so that an illumination area matching the command value is exposed.

Reference numeral 111 denotes a console unit for giving the main CPU 107 various job parameters relating to the operation of the exposure apparatus. That is, it is for teaching information with the operator. 112 is a console CPU, 113 is a display, 114 is a keyboard, and 115 is an external memory for storing various job parameters and the like.

FIG. 2 is a configuration diagram showing a state where the present invention is embodied in this exposure apparatus. In FIG.
Reference numeral 1 denotes a console control unit having input / output functions such as screens and keyboards of elements 112 to 115 in FIG.
202 receives an instruction from the console control unit 201,
It is a system control unit that controls the control unit of each unit constituting the device. A masking blade control unit 203 controls the driving of the masking blade in response to an instruction from the system control unit 202. A masking blade drive unit 210 actually drives the masking blade in response to the instruction from the masking blade control unit 203. It is. 2
Reference numeral 21 denotes a light source of the exposure light, and reference numeral 222 denotes a shutter for controlling emission of the exposure light from the light source 221. A masking blade 223 limits an exposure area by blocking a part of exposure light emitted when the shutter 222 is open. Reference numeral 224 denotes a reticle on which a mask pattern to be exposed is drawn. The reticle 224 is mounted on a reticle stage 229 movable in the left, right, and vertical directions in FIG.
Exposure light limited by the masking blade 223 is applied. Reference numeral 225 denotes a lens that projects a pattern at a specific scale, and forms light transmitted through the reticle 224 on an image forming surface. A wafer stage 227 is provided on the image forming surface, on which a wafer 226 to be exposed is placed. An optical sensor 228 for measuring the illuminance of the exposure light under the lens 225 also exists on the wafer stage 227.

FIG. 3 is a diagram showing the difference between the case where the exposure area is limited only by the masking blade 223 and the case where the exposure area is limited using a reticle having a light-shielding band. In the case where the exposure area is limited only by the masking blade 223, as shown in FIG. 9A, the exposure area of the exposure light 304 is determined by the masking blade 223. Thus, the light passes through the reticle 224 and reaches the wafer 226 without limiting the exposure area. As shown in FIG. 4B, when the exposure area is limited using a reticle 312 having a light-shielding band 314, the exposure light 304 is exposed by the masking blade 223 to an area where the reticle light-shielding band 314 can be shielded. Is limited, and the final exposure area is determined by the light-shielding band 314 printed so as to surround the outer periphery of the reticle 312, and reaches the wafer 226.

When the operation shown in FIG. 3B is performed by the reticle 312 having the light-shielding band, the width of the reticle light-shielding band 314 can be input as an offset of the masking blade 223 from the console control unit 201 shown in FIG. . The input value is added as an offset in the opening direction of the masking blade 223 when the masking blade 223 is driven, so that the control automatically takes into account the light-shielding band 314 of the reticle.

FIG. 4 is a flowchart for driving the masking blade 223 when the exposure area is limited using the reticle 312 having the light-shielding band 314. When the drive control of the masking blade 223 is started, first, in step 401, the opening width of the masking blade 223 is obtained. Next, in step 402, the light-shielding band width of the reticle 312 is obtained. Next, in step 403, the masking blade 22 is added to the target position obtained in step 401 by adding の of the light shielding band width of the reticle 312 obtained in step 402 in the opening direction.
3 is calculated. Then, step 404
In FIG. 2, the masking blade driving unit 210 shown in FIG.
The masking blade 223 is driven by transmitting the drive target position calculated in step 403.

For example, assuming that the exposure area is 20 × 20 and the width of the reticle light-shielding band 314 is 2, the masking blade 223 normally operates as shown in FIG. 5 when a 20 × 20 exposure area is designated. In an XY coordinate system where the shot center is 0 as shown in FIG.
There is only zero opening. However, in this embodiment, the offset for the reticle light-shielding band width is newly provided, and the width of the reticle light-shielding band 314 is previously input as “2” from an input / output device such as the keyboard 113 and the display 114 in FIG. Then, “1”, which is の of “2”, which is the input reticle light-shielding band width, is used as the masking blade 2
When the masking blade 223 is added in the opening direction of the masking blade 23, the masking blade 223 opens in ± 11 directions in the X and Y directions. By doing so, the reticle light-shielding band is used as shown in FIG.
The exposure area can be limited. The parameter of the reticle light-shielding band width may be provided as a parameter unique to the device as an offset for each device, or may be provided as an offset for each reticle.

By performing such control, the position of the masking blade actually driven is conventionally the same as the value designated by the parameter of the masking blade. Therefore, the value becomes larger in the opening direction by の of the width of the reticle light-shielding band. Therefore, it is difficult to immediately obtain the opening width of the masking blade. Therefore, as shown in FIG. 8, the opening width of the masking blade can be displayed so as to be superimposed on the shot layout on the portion where the shot layout on the wafer is displayed, so that the shot layout can be easily recognized.

(Embodiment 2) In the first embodiment, the reticle light-shielding band width is input as a parameter. However, without inputting as a parameter, the reticle itself may be provided with data and read by a reader, or a reticle may be read. It is also possible to perform automatic measurement by driving in the X or Y direction and observing the transmitted light.

FIG. 6 is a flowchart showing a case where the reticle is driven in the X or Y direction and the reticle light-shielding band width is obtained by observing the transmitted light. FIG. 7 shows the configuration in that case. 7, the same reference numerals as those in FIG. 2 indicate the same elements. Reference numeral 724 denotes a reticle having a reticle light-shielding band width; 710, a reticle stage drive control unit that controls the reticle stage 229 in the horizontal and vertical directions in the figure; 711, a wafer stage that drives and controls the wafer stage 227 in the horizontal and vertical directions in the figure. Drive control unit, 71
Reference numeral 2 denotes a light amount calculation unit that calculates the intensity of the light received by the optical sensor 228, and reference numeral 701 denotes a reticle stage drive control unit 710, a wafer stage drive control unit 711, and a light amount calculation unit 712.
Is a system control unit that manages

In this configuration, when the process of acquiring the reticle light-shielding band width of the reticle 724 is started, first, as shown in FIG. 6, an effective pattern area of the reticle 724 is acquired in step 601. Next, in step 602, the opening width of the masking blade 223 is minimized. Next, in step 603, the reticle stage 229 is driven to move the reticle 724 to the outer peripheral position of the effective pattern area of the reticle 724, which corresponds to the measurement start position of the reticle light-shielding band width. Next, step 604
, The wafer stage 227 is moved so that the optical sensor 228 is located below the lens 225, and the reticle 724 is moved.
To measure transmitted light. Next, step 605
At, the shutter 222 is opened to irradiate the reticle 724 with light, and the reticle stage 229 is driven in the outer peripheral direction of the reticle 724 to observe the transmitted light of the reticle 724. Then, using the luminance obtained from the light amount calculation unit 712 and the movement amount obtained from the reticle stage drive control unit 710, the drive amount of the reticle stage 229 from the light shielding start position where the light intensity is 0 to the end is measured. Get the width of the reticle shading zone.

<Embodiment of Device Manufacturing Method> Next, an embodiment of a device manufacturing method using the above-described exposure apparatus will be described. FIG. 9 shows a flow of manufacturing micro devices (semiconductor chips such as ICs and LSIs, liquid crystal panels, CCDs, thin-film magnetic heads, micromachines, etc.). In step 1 (circuit design), a device pattern is designed. Step 2 is a process for making a mask on the basis of the designed pattern. On the other hand, in step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon or glass.
Step 4 (wafer process) is called a pre-process, and 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 an assembly process (dicing, bonding),
It includes steps such as a packaging step (chip encapsulation). 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. 10 shows a detailed flow of the wafer process (step 4). 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. In step 15 (resist processing), a resist is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus or exposure method to align and print the circuit pattern of the mask on a plurality of shot areas of 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), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the production method of this embodiment, it is possible to produce a large-sized device, which was conventionally difficult to produce, at low cost.

[0028]

As described above, according to the present invention, when the operator sets the opening width of the masking blade, the opening width of the masking blade can be made the same as the element spacing on the wafer, thereby reducing operational errors. Will be possible. In addition, exposure processing using an original plate having a light-shielding band can be easily performed, and a decrease in drawing accuracy near the light-shielding portion can always be prevented.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a semiconductor device exposure apparatus according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing a state in which the present invention is embodied in the exposure apparatus of FIG.

FIG. 3 is a diagram illustrating a method of blocking exposure light in the configuration of FIG. 2;

FIG. 4 is a flowchart in a case where a masking blade is driven when an exposure area is limited using a reticle in the configuration of FIG. 2;

FIG. 5 is a diagram showing a state of an opening of a masking blade in the configuration of FIG. 2;

FIG. 6 shows a second embodiment of the present invention in a case where a reticle light-shielding band width is obtained by driving a reticle and observing transmitted light.
FIG. 3 is a diagram showing a configuration according to an example of FIG.

FIG. 7 is a flowchart showing an operation in the configuration of FIG. 6;

FIG. 8 is a diagram showing a state in which an opening width of a masking blade is displayed so as to overlap a shot layout according to the present invention.

FIG. 9 is a flowchart illustrating a device manufacturing method that can use the exposure apparatus of the present invention.

FIG. 10 is a detailed flowchart of a wafer process in FIG. 9;

[Explanation of symbols]

101: laser light source, 102: illumination system, M: mask or reticle, 103: projection optical system, W: wafer, 10
9: masking blade, 104: mirror, 105: sensor, 106: light intensity integration circuit, 107: CPU, 10
8: laser controller, 109: masking blade, 11
0: masking blade controller, 111: console unit, 112: console CPU, 113: display, 114: keyboard, 115: external memory, 20
1: console control unit, 202: system control unit, 20
3: masking blade control unit, 210: masking blade driving unit, 221: light source, 222: shutter, 22
3: Masking blade, 224: reticle, 225:
Lens, 226: wafer, 227: wafer stage, 2
28: Optical sensor, 229: Reticle stage, 304:
Exposure light, 312: reticle, 314: light-shielding band, 701:
710: reticle stage drive controller, 711: wafer stage drive controller, 712: light amount calculator, 724: reticle.

Claims (6)

[Claims] In an exposure apparatus for exposing an area other than an exposure area with a masking blade when exposing a pattern of an original onto a substrate, when exposing using an original having a light-shielding band, the exposure area The position of the masking blade is controlled such that the position of the masking blade is located at the center of the width of the light-shielding band based on the position of the masking blade that is set to coincide with the width of the light-shielding band. An exposure apparatus comprising control means. 2. An exposure apparatus, comprising: means for obtaining the width of the light-shielding band by moving the substrate and observing light transmitted through the substrate. 3. An apparatus for displaying a shot layout, comprising means for controlling an opening of the masking blade located under the control of the control means when exposure using an original plate having the light-shielding band is performed. 3. The exposure apparatus according to claim 1, wherein the image is displayed so as to be superimposed on the shot layout. 4. 4. An exposure method for exposing an area other than an exposure area with a masking blade when exposing a pattern of an original onto a substrate, wherein the exposure is performed using an original having a light-shielding band. The exposure device of the above, by the control means, based on the position of the masking blade set to match the exposure area and the width of the light shielding band, the position of the masking blade is the width of the light shielding band An exposure method, wherein the position of the masking blade is controlled so as to be located at the center. 5. A device manufacturing method, wherein a device is manufactured by performing exposure by the exposure method according to claim 4. 6. The method according to claim 4, further comprising a step of acquiring the width of the light-shielding band when performing exposure using the original plate having the light-shielding band. .