JP2001217182A - Sensor control device and aligner using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sensor control device which satisfactorily sensitivity characteristic of a sensor, irrespective of the reverse voltage to a sensor and illumination shapes of an incident light and can detect exposure on a prescribed surface with superior precision, and an aligner using the sensor control device. SOLUTION: When luminous flux, which is radiated from a light source and made to enter on the specified surface, is received with a sensor 202a to which a puscribed reverse voltage is applied with a backward voltage controller 207, control is performed by a method, where the backward voltage due to the backward voltage applying part 207 is controlled by a control means which is based on an output signal from the sensor 202a and a signal from a console 209 as an input means, and an output value of the sensor 202a is corrected by using correlation between the respective different illumination shapes, which are based on sensitivity characteristics of the sensor 202a which are caused by illumination shapes. In an aligner using this sensor control device, integrated exposure is controlled, and the backward voltage is controlled dynamically, so that a pattern image having high resolution can be obtained over a wide area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor control device and an exposure apparatus using the same, and more particularly to a sensor control device which appropriately controls a sensor for detecting a light beam from various light sources.
It is suitable for controlling an exposure amount on a predetermined surface in a lithography step in a process of manufacturing a semiconductor device such as a semiconductor device, an LSI, or the like, an imaging device such as a liquid crystal device, a CCD, or a magnetic head.

[0002]

2. Description of the Related Art In an exposure apparatus which requires miniaturization of an IC pattern, strict accuracy is required for an exposure amount irradiated on a photosensitive substrate (wafer). For this reason, an excimer laser light source having a shorter wavelength than the i-line of a mercury lamp, which has been conventionally used, has been used for the wavelength of the exposure light to increase the resolution. This excimer laser light source is a pulse light that emits light discontinuously and has an upper limit of 2.5 ms.
The actual light emission time is several tens of nsec with respect to the light emission interval of ec.

Also, the excimer laser light source has a property that the light intensity of the pulse light is not constant and changes with each pulse. Therefore, in an exposure apparatus using an excimer laser as a light source, various methods have been proposed in which the integrated exposure amount on a photosensitive substrate (wafer) becomes a predetermined value.

For example, a method of controlling the number of pulses to be exposed and the energy of each pulse, and a method of controlling the interval between individual pulses to be exposed in an exposure apparatus have been proposed. Of these, Japanese Patent Laid-Open No. 4-69660 discloses that
For each pulse from the first pulse, subtract the already exposed exposure from the total exposure, calculate the exposure of the next one pulse from the remaining exposure, and propose a method of controlling the exposure variable means. I have.

In Japanese Patent Application Laid-Open No. 5-62876,
The average energy per pulse of the remaining light amount and the average one pulse exposure amount up to several times before are compared for each pulse, and the control parameters are set so that the next exposure amount matches the average energy per pulse of the remaining light amount. We propose a way to change it.

In Japanese Patent Application Laid-Open No. 7-074092, the amount of exposure by each pulsed light is monitored while the scanning speed is kept constant in a slit scanning type exposure apparatus, and the next exposure is performed according to the intensity of the measured exposure. The emission timing of the pulsed light is shifted back and forth in time, and the intensity distribution of the slit light in the scanning direction has a gradual change in the boundary region, so that the above-described deterministic error of the integrated exposure amount does not occur. Suggest a way.

As a sensor control method, Japanese Patent Laid-Open No. 9-2
According to Japanese Patent Publication No. 05053, a sensor to which a predetermined reverse voltage is applied by a reverse voltage applying unit and received by a sensor applied with a predetermined reverse voltage by changing the opening diameter of a light beam emitted from a light source and incident on a sensor surface to obtain a predetermined irradiation diameter. By controlling the reverse voltage applied to the sensor and the irradiation light diameter of the irradiation light according to the intensity of the light incident on the sensor and the life required of the sensor, it is possible to eliminate the dispersion of the measurement values due to the intensity of the light incident on the sensor Proposed.

On the other hand, as for the illumination shape, there is an image improvement technique called deformed illumination. In the case of normal illumination, FIG.
When illuminated vertically as shown in FIG. 3, three light beams of 0-order light and ± 1st-order light diffracted on the pattern surface interfere with each other on the photosensitive substrate (wafer) surface to form a pattern image. On the other hand, in the modified illumination for illuminating the reticle surface obliquely, FIG.
As shown in FIG. 0 (b), two light fluxes of either the 0th order light and the ± 1st order light interfere with each other on the wafer surface to form a pattern image.
Compared with the conventional three-beam interference of the zero-order light and the ± first-order light, the two-beam interference can obtain higher resolution and depth of focus. To realize deformed illumination, for example, it has been proposed to form a secondary light source using a diaphragm whose central portion is shielded from light, as shown in FIGS. 11A and 11B.

[0009]

In an exposure apparatus using a pulse light source as a light source, it is difficult to control the amount of light for each pulse at a constant level as compared with a conventional exposure apparatus using, for example, a mercury lamp as a light source. It is difficult to make the integrated exposure amount on the photosensitive substrate constant.

In particular, in pulse light intensity measurement using a sensor, an angle characteristic exists depending on the sensor, and the angle of illumination light incident on the sensor changes due to a difference in illumination shape, and the output of the sensor is 0.5 to 2 It has been confirmed that the variation varies by about 0.0 times, and the sensitivity characteristic of the sensor changes for each illumination shape. As a result, there is a problem that the exposure amount control result is greatly affected.

Further, in the conventional exposure apparatus, there is a problem that it is difficult to control the exposure amount with high precision because the sensitivity characteristic of the measurement depending on the illumination shape and its change are not taken into account when controlling the exposure amount.

A first object of the present invention is to provide a sensor control device capable of removing variations in the sensitivity characteristics of a sensor for each illumination shape, controlling the sensitivity of the sensor to the amount of incident light, and accurately detecting the amount of light on a predetermined surface. It is to provide.

A second object of the present invention is to provide an exposure apparatus equipped with the above-described sensor control device capable of performing exposure while keeping the integrated exposure amount constant, and obtaining a high-resolution pattern image over a wide area. It is to provide a method for manufacturing a device.

[0014]

In order to achieve the first object described above, a sensor control device according to the present invention comprises an illumination shape of a light beam emitted from a light source and incident on a predetermined surface on which a sensor is arranged, and It is characterized by having a correction means for correcting a sensitivity characteristic of the sensor, which is a relationship between an amount of light incident on the sensor and an output value from the sensor, by controlling a reverse voltage applied to the sensor.

In the sensor control device according to the present invention, an illumination system control means for forming a light beam emitted from the light source and incident on a predetermined surface into a predetermined illumination shape via an illumination optical system, Light amount detecting means for receiving a light beam incident on the sensor by a sensor to which a predetermined reverse voltage is applied by a reverse voltage applying unit, and reverse voltage controlling means for controlling a reverse voltage applied to the sensor by the reverse voltage applying unit. Calculating means for dynamically controlling an input signal to the reverse voltage control means in order to control an output value from the sensor in accordance with an output value from the sensor disposed on a predetermined surface and an input value by an operator; Can be provided.

The control signal input to the reverse voltage application section of the reverse voltage control means includes the illumination shape, the amount of light incident on the sensor, the sensitivity characteristic of the sensor, the life of the sensor, and the response time of the sensor. Based on any one or more of

The output control means may use a data table created in advance using the illumination shape and the reverse voltage applied to the sensor as parameters for the sensitivity characteristics of the sensor.

Preferably, the light source oscillates pulsed light. Further, the sensor includes a mechanism for changing an illumination position of a light beam with respect to a sensor surface, a circuit configuration for adjusting a reverse voltage applied to the sensor, and a mechanism for irradiating an arbitrary position with the light beam. can do.

In order to achieve the above-mentioned second object, the exposure apparatus of the present invention illuminates a pattern on a first object surface with pulse light from a light source means by an illumination means, and When projecting and exposing a pattern on a second object surface mounted on a movable stage by a projection optical system, a sensor is arranged on the first object surface or the second object surface, and the sensor is used to project the first object surface or the second object surface. An exposure apparatus for detecting an integrated exposure amount of pulsed light irradiating a second object surface, and controlling the integrated exposure amount by a control unit using an output value from the sensor, comprising the sensor control device described above, It is characterized in that the reverse voltage to the sensor is dynamically controlled.
Further, a device can be manufactured using the exposure apparatus.

[0020]

Next, embodiments of the present invention will be described with reference to the drawings. [Embodiment] FIG. 1 is a schematic view of a main part of a scanning type exposure apparatus having a sensor control device according to one embodiment of the present invention. In the figure, a reticle (first object) is irradiated with a light beam emitted from a pulse laser light source via an illumination optical system (illumination means).
Projection lens for the circuit pattern formed on the reticle
(Projection optical system) This is a scanning type exposure apparatus that prints by reducing and projecting while scanning onto a substrate (second object) coated with a photoreceptor by a (projection optical system). Semiconductor devices such as ICs and LSIs, liquid crystal devices, CCDs, etc. This is suitable for manufacturing a device such as an imaging device or a magnetic head.

In FIG. 1, reference numeral 1 denotes a light source (light source means), which is constituted by a pulse laser such as an excimer laser and emits pulse light. Reference numeral 2 denotes a beam shaping optical system, and a light source 1
Is shaped into a predetermined illumination shape and is incident on the light incident surface 3a of the optical integrator 3. The beam shaping optical system is provided with, for example, a σ stop turret (not shown), and the illumination shape is changed using a stop as shown in FIGS. 11 (a) and 11 (b). The optical integrator 3 is composed of a fly-eye lens or the like composed of a plurality of minute lenses, and its light exit surface 3b
Are formed in the vicinity of. Reference numeral 4 denotes a condenser lens which illuminates a movable slit (masking blade) 6 with a light beam from a secondary light source near the light exit surface 3b of the optical integrator 3.

The light beam illuminating the movable slit 6 illuminates the reticle 9 via the imaging lens 7 and the mirror 8.
The movable slit 6 and the reticle 9 are in an optically conjugate positional relationship.
Specifies the shape and dimensions of the illumination area. Movable slit 6
Is provided with, for example, a voice coil motor (not shown), and controls the movement of the movable slit 6 in the optical axis direction. Reference numeral 12 denotes an exposure detector A, which includes a sensor and a sensor control device described later. Exposure detector A1
A sensor control device 2 is capable of changing the reverse voltage by the sensor control device, detects the light amount of a part of the pulsed illumination light divided by the half mirror 5, and outputs a signal to the exposure calculator 102.

The beam shaping optical system 2, optical integrator 3, condenser lens 4, movable slit 6, imaging lens 7, mirror 8, etc.
Of the illumination means (exposure light supply means) for supplying light to the light source. Further, among the illuminating means, there is a not-shown dimming means, which has a configuration capable of adjusting the amount of light flux from the light source 1 in multiple stages. The reticle (first object) 9 has a circuit pattern on its surface and is held on a reticle stage 13. Reference numeral 10 denotes a projection lens (projection optical system) which reduces and projects the circuit pattern of the reticle 9 on a semiconductor substrate (second object) 11. The semiconductor substrate 11 is a so-called wafer, the surface of which is coated with a resist which is a photosensitive member, and is mounted on a wafer stage 14 which is displaced three-dimensionally. The surface of the wafer 11 is at a position conjugate with the movable slit 6.

On the wafer stage 14, an exposure detector B15 having a sensor and a sensor control device described later is provided. The exposure amount detector B15 measures the amount of pulsed light and the integrated exposure amount via the projection lens 10 as described later.

The exposure detector A12 can measure the intensity even during exposure, and is used for estimating the integrated value of the exposure light emitted from the slit. Exposure detector B15
Is used to measure the intensity of the pulse light that passes through the projection lens 10 and irradiates the wafer 11 at the beginning of the exposure process.

Reference numeral 101 denotes a stage drive control system (scanning means)
The reticle stage 13 and the wafer stage 14 are controlled so as to be moved in the opposite directions at a constant speed and accurately at the same ratio as the imaging magnification of the projection lens 10. The exposure calculator 102 converts the electrical signal photoelectrically converted by the exposure detector A12 and the exposure detector B15 into a logical value and outputs the logical value to the main control system 104.
O4 is stored in the internal storage means.

In each exposure, a correlation between the intensity of the light detected by the exposure detector A12 and the measured value from the exposure detector B15 is obtained, and the obtained correlation is used by utilizing the obtained correlation. Is corrected, and the exposure amount on the wafer is obtained. The exposure detector B15 does not measure the exposure light intensity during the exposure of the wafer.

Reference numeral 103 denotes a laser control system which outputs a trigger signal 16 and a charging voltage signal 17 in accordance with a desired exposure amount to control the pulse energy and the light emission interval of the light source 1.
When the laser control system 103 generates the trigger signal 16 and the charging voltage signal 17, the illuminance monitor signal 108 from the exposure calculator 102, the stage current position signal 107 from the stage drive control system 101, and the main Control system 10
4 is used as a parameter.

The main control system 104 obtains parameters necessary for scanning exposure from the data provided from the input unit 105, parameters unique to the exposure apparatus, and data measured by measurement means such as the exposure detector A12 and the exposure detector B15. By calculating the group, the laser control system 103, the stage drive control system 101,
The light is transmitted to the beam shaping optical system 2.

The exposure amount detector A12 and the exposure amount detector B15 in the present embodiment can change the reverse voltage applied to the sensor by the reverse voltage applying unit, change the incident light beam by the aperture member having a variable aperture, and the like. With this configuration, while maintaining good measurement variation due to the intensity of light incident on the sensor, high-precision control is performed so that the integrated exposure amount on the semiconductor substrate 11 becomes a predetermined value.

The exposure amount detector B15 in this embodiment has two purposes, that is, monitoring the exposure amount and performing alignment. The light amount at that time may differ by more than two digits. In order to accurately measure the light amount having such a wide band, it is difficult to measure the light amount with one sensor. Further, in a semiconductor exposure apparatus, the accuracy of exposure unevenness required at that time varies for each layer, but it is difficult to perform measurement according to the change.

Therefore, in this embodiment, the exposure amount detector A1
2 and the exposure detector B15 in combination with a sensor control device to be described later to reduce the amount of light having a wide bandwidth to 1
Since the measurement can be performed with high accuracy by one sensor unit, less space is required as compared with the case where two sensor units are conventionally used, which is advantageous in configuration.

Next, a sensor control device applied to the exposure detector A12 and the exposure detector B15 of this embodiment will be described. FIG. 2 is a main block diagram of the sensor control device of the present embodiment. 2 includes a sensor unit 202 that can dynamically control a reverse voltage,
It comprises a console 209 from which the control state of the reverse voltage of the sensor can be observed. In the figure, a collimator lens 201 condenses a light beam (light flux) and irradiates the sensor unit 202, but is not always necessary as a sensor control device.

The sensor unit 202 has a mechanism capable of changing the irradiation position of the light beam on the sensor surface 202b, a circuit configuration capable of adjusting a reverse voltage to the sensor 202a,
A mechanism (Zθ stage 202c) capable of irradiating a light beam to an arbitrary position is provided. Sensor unit 50
2 is integrated by the integrator 203 for a certain period of time, and the variable amplifier 204 integrates the output.
Are adjusted and input to the arithmetic unit 206 via the A / D converter 205.

In the arithmetic unit 206, measured values of the illumination shape and the like, and data (input values) input by the operator
, A command signal is output to each of the variable amplifier 204, the sensor reverse voltage controller (reverse voltage application unit) 207, and the sensor position adjustment driver 208. The reverse voltage controller 207 applies a specified reverse voltage to the sensor unit 202 according to a command from the calculator 206. The sensor position adjustment driver 208 gives a command signal to the sensor position adjustment servo system (Zθ stage 202c) of the sensor unit 202, and adjusts the position of incident light irradiated on the sensor surface 202b. The console 209 is used as an interface for inputting data such as the reverse voltage and the irradiation shape of the sensor 202a and displaying the value on a display unit. Note that the console 209 in FIG. 2 can be replaced with the input unit 105 and the display unit 106 in FIG.

FIG. 3 shows the sensor unit (sensor) shown in FIG.
FIG. 9 is an explanatory diagram showing the linearity of the output from the sensor unit 202 with respect to the amount of incident light when the reverse voltage is changed with respect to 202. Since the output from the sensor unit 202 has fixed output linearity, the sensor surface 50
When the pulse light of a wide light amount area is irradiated to 2b, it becomes impossible to measure an accurate light amount in an area where linearity is not guaranteed. Therefore, in order to perform accurate measurement, the amount of measurement light is limited.

Curves 301 to 304 in FIG. 3 show the relationship between the amount of light incident on the sensor 202 (FIG. 2) and the output from the sensor 202 when the reverse voltage is changed. When the reverse voltage applied to the sensor is changed, the output result is represented by curves 301, 302, and 3 as the reverse voltage is increased.
After passing through 03, it changes like a curve 304.

Further, since the sensitivity characteristic of the sensor changes depending on the illumination shape, the inclination of the straight line 305 in FIG.
The measurement value of the sensor changes from the straight line 305 to 306 or 307 depending on the illumination shape.

FIG. 4 shows the sensor 202 in this embodiment.
FIG. 4 is an explanatory diagram showing the output ratio of the sensor 202 to the amount of light incident on the sensor 202 when the reverse voltage to (FIG. 2) and the illumination shape are changed, for different illumination shapes A to C. As the reverse voltage is changed, the sensitivity characteristic curve 401 of the sensor has an incident light amount axis 4 like the sensitivity characteristic curve 402.
It moves along arrow 04 as indicated by arrow 403. When the illumination shape incident on the sensor surface 202a (FIG. 2) is changed, the sensitivity characteristic curve 401 generally becomes the sensitivity characteristic curve 406.
Move stepwise as indicated by an arrow 405 along the axis of the illumination shape.

Therefore, in this embodiment, when the incident light quantity is determined, the reverse voltage applied to the sensor is adjusted to move the sensitivity characteristic curve along the incident light quantity axis 404, and further, the arithmetic unit 206 (FIG. 2) By correcting the sensor output value from the sensor sensitivity characteristic for each illumination shape calculated in advance, the sensitivity characteristic curve is shifted in consideration of the sensitivity characteristic of the sensor for each illumination shape.

Various methods are conceivable for obtaining the correction amount for the sensitivity characteristic of the incident light incident on the sensor depending on the illumination shape. For example, using another sensor that is not affected by the illumination shape, or a sensor in which the effect of the illumination shape is quantitatively determined, a measurement value is obtained for each illumination shape,
The correlation with the sensor output used in the present embodiment is obtained in advance, and a method of holding the sensitivity characteristic curve of FIG. 4 as a data table for each illumination shape and a reference illumination shape are determined.
A method can be used in which the correlation between the sensor output in the reference illumination shape and the sensor output in another illumination shape is obtained in advance, and the sensitivity characteristic curve in FIG. 4 is stored as a data table for each illumination shape. Further, a method of correcting the sensor output based on the obtained correlation at the time of controlling the exposure amount can be applied. In addition, factors that determine an optimal reverse voltage from a range that satisfies the required performance include a response speed and a frequency characteristic of the sensor. The response time of the sensor depends on the characteristics of the sensor, such as the junction capacitance of the sensor, but also depends on the reverse voltage applied to the sensor. In general, when the voltage applied to the sensor is increased, the response time of the sensor at that time is shortened. Therefore, the reverse voltage may be determined in consideration of the response time.

FIG. 5 is a diagram showing sensor sensitivity characteristics used in a sensor sensitivity characteristic table as described later.

FIG. 6 is a flowchart of the present embodiment for determining the reverse voltage to the sensor and the correction amount for each illumination shape. First, in step 601, a sensor sensitivity characteristic table (data table) is created. As shown in the sensor sensitivity characteristic of FIG. 5, the sensor sensitivity characteristic table calculates the sensitivity characteristic with respect to the amount of incident light by changing the reverse voltage to the sensor, and the illumination shape and the reference incident on the sensor. The correlation of the output of the sensor in a different illumination shape is obtained. In addition, since the accuracy at this time greatly affects the control performance of the sensor, the accuracy of the data is improved by taking data several times and averaging the data.

Next, in step 602, the amount of incident light and the illumination shape are input. In step 603, the sensitivity characteristics required for the sensor are input. From the sensor sensitivity characteristic table obtained in step 601, the range of the reverse voltage satisfying the requirements is obtained. Is determined. Then, in step 604, the ratio between the reference illumination shape and the sensor sensitivity characteristics of the illumination shape to be measured is calculated from the illumination shape used for measurement and the sensor sensitivity characteristic table.

FIG. 5 shows the sensor sensitivity characteristics used in the sensor sensitivity characteristic table. At this time, step 602 (FIG. 6)
Is 506. When the illumination shape is the illumination shape A, a point 507 on the sensitivity characteristic curve 502 is obtained to determine the reverse voltage to the sensor and the correction amount of the sensitivity characteristic in the illumination shape A. Similarly, when the incident light amount is 506 and the illumination shape B, the reverse voltage to the sensor and the correction amount of the sensitivity characteristic for the illumination shape B are determined from the point 508 on the sensitivity characteristic curve 504. In addition, the illumination shape A and the incident light amount 5
Similarly, in the case of 09, a point 510 is obtained from the sensitivity characteristic curve 502.
, The reverse voltage to the sensor and the illumination shape A
The amount of correction of the sensitivity characteristic with respect to is determined.

Further, when the incident light amount is 511 and the illumination shape A
In the case of (1), the reverse voltage to the sensor is determined from the point 512 on the sensor sensitivity characteristic curve 503, and the correction amount of the sensor sensitivity characteristic for the illumination shape A is determined. Similarly, in the case of the incident light amount 511 and the illumination shape B, a point 513 is obtained from the sensor sensitivity characteristic curve 505, and the amount of correction of the reverse voltage to the sensor and the sensitivity characteristic for the illumination shape B is determined. At this time, other items that need to be considered (such as the life of the sensor) may be input.

In step 605 of FIG. 6, the optimum value in light quantity measurement using a sensor is determined from the reverse voltage obtained in steps 603 and 604 and the correction value for the illumination shape.

FIG. 7 is a flowchart when the sensor control device of the present embodiment is applied to the scanning exposure apparatus of FIG. In the figure, first, in step 701, the purpose of the measurement to be performed, that is, whether to measure the exposure amount or the alignment light, is input, and the illumination shape to be irradiated on the sensor surface and the amount of light are estimated. At the same time, the measurement accuracy required for the measurement is also input.

In the next step 702, a use condition required for the sensor, that is, whether the life of the sensor or the measurement speed is to be emphasized is input. Then, in step 703, a reverse voltage required for the measurement is determined, and the process proceeds to an exposure process. In step 704, the emission intensity is measured. In step 705, the next emission intensity is calculated from the exposure amount. In step 706, the laser is emitted. In step 707, it is determined whether the exposure process has been completed. The exposure process for finding the intensity is repeated.

[Embodiment of Device Manufacturing Method] Next, an embodiment of a device manufacturing method using the above-described exposure apparatus will be described. FIG. 8 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 step 4
Is a process of forming a semiconductor chip using the wafer produced by the above process, and includes processes such as an assembly process (dicing and bonding) and a packaging process (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. 9 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 1
In 5 (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), 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 highly integrated device, which was conventionally difficult to produce, at low cost.

[0053]

As described above, according to the present invention, the sensitivity characteristic of the sensor is measured in advance in accordance with the illumination shape of the sensor, and the correlation between the reference illumination shape and the desired illumination shape is determined. By correcting the output value of the sensor according to the variation of the sensitivity characteristic of the measured value from the sensor due to the illumination shape, the sensitivity of the sensor is controlled by controlling the reverse voltage applied to the sensor with respect to the amount of incident light. A sensor control device for controlling can be provided.

Further, according to the present invention, when exposing a pattern on the first object surface illuminated with pulse light from the light source means for oscillating pulse light onto the second object surface, Light intensity (exposure amount) on the second object surface (exposure surface)
An exposure apparatus and a device manufacturing method using the same that can perform exposure while keeping the integrated exposure amount constant by appropriately setting a sensor control device that detects Can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a main part of a scanning exposure apparatus having a sensor control device according to one embodiment of the present invention.

FIG. 2 is a main block diagram of the sensor control device of the present embodiment.

FIG. 3 is an explanatory diagram showing the amount of incident light and the linearity of output when the reverse voltage to the sensor is changed in the sensor control device of the present embodiment.

FIG. 4 is an explanatory diagram showing a sensor sensitivity characteristic based on a ratio between an incident light amount and an output when a reverse voltage to the sensor and an illumination shape are changed in the sensor control device of the present embodiment.

FIG. 5 is a diagram illustrating sensor sensitivity characteristics used in a sensor sensitivity characteristic table (data table) in the sensor control device according to the present embodiment.

FIG. 6 is a flowchart for determining a reverse voltage to a sensor and a correction amount for each illumination shape in the sensor control device of the present embodiment.

FIG. 7 is a flowchart in the case where the sensor control device of the present embodiment is applied to the scanning exposure apparatus of FIG. 1;

FIG. 8 is a diagram showing a flow of manufacturing a micro device.

FIG. 9 is a diagram showing a detailed flow of a wafer process in FIG. 8;

FIG. 10 is a diagram showing a schematic diagram of a light beam in deformed illumination.

FIG. 11 is a diagram showing a shape of a diaphragm in modified illumination.

[Explanation of symbols]

1: pulse laser light source, 2: beam shaping optical system, 3: optical integrator, 3a: light entrance surface of optical integrator, 3b: light exit surface of optical integrator, 4: condenser lens, 5: half mirror, 6: movable slit (Masking blade), 7: imaging lens, 8: mirror, 9: reticle, 10: projection lens (projection optical system), 11: wafer, 12: exposure detector A, 13: reticle stage, 14: wafer stage ,
15: Exposure detector B, 16: Trigger signal, 17: Charge voltage signal, 101: Stage drive control system, 102: Exposure calculator, 103: Laser control system, 104: Main control system,
105: input unit, 106: display unit, 107: current position signal, 108: illuminance monitor signal, 109: intensity command value, 1
10: illumination shape signal, 201: collimator lens, 20
2: sensor unit, 202a: sensor, 202b: sensor surface, 202c: Zθ stage, 203: integrator, 2
04: Variable amplifier, 205: A / D converter, 20
6: arithmetic unit, 207: reverse voltage controller (reverse voltage application unit), 208: sensor position adjustment driver, 209: console, 301, 302, 303, 304: incident light quantity to sensor using reverse voltage as a parameter vs. sensor output curve,
305, 306, 307: incident light quantity versus sensor output linearity with illumination shape as a parameter, 401, 40
2, 406: a sensitivity characteristic curve using reverse voltage and illumination shape as parameters; 403: an arrow indicating a moving direction of the sensitivity characteristic curve using reverse voltage as a parameter; 404: incident light amount axis;
5: Arrow indicating the moving direction of the sensitivity characteristic curve using the illumination shape as a parameter, 502, 503, 504, 505: Reverse voltage, sensitivity characteristic curve using the illumination shape as a parameter, 50
6,509,511: Incident light amount, 507,508,51
0,512: A point for determining the reverse voltage when the incident light amount and the illumination shape are known.

Claims (8)

[Claims] A correction means for correcting sensitivity characteristics of the sensor by controlling an illumination shape of a light beam emitted from a light source and incident on a predetermined surface on which the sensor is disposed and a reverse voltage applied to the sensor. Characteristic sensor control device. 2. An illumination system control means for converting a light beam emitted from the light source and incident on a predetermined surface into a predetermined illumination shape via an illumination optical system, and a light beam emitted from the light source and incident on the predetermined surface is inverted. A light amount detecting unit that receives light by a sensor to which a predetermined reverse voltage is applied by a voltage applying unit; and a reverse voltage control unit that controls a reverse voltage that is applied to the sensor by the reverse voltage applying unit. An arithmetic unit for controlling an input signal to the reverse voltage control unit for controlling an output value from the sensor according to an output value from the arranged sensor and an input value by an operator. Item 2. The sensor control device according to item 1. 3. The control signal input to the reverse voltage application unit of the reverse voltage control means includes the illumination shape, the amount of incident light on the sensor, the sensitivity characteristic of the sensor, the life of the sensor, and the response time of the sensor. 3. The sensor control device according to claim 2, wherein the sensor control device is based on at least one of the following. 4. The output control means uses a data table created in advance using the illumination shape and a reverse voltage applied to the sensor as parameters for the sensitivity characteristic of the sensor. The sensor control device according to claim 1. 5. The sensor control device according to claim 1, wherein the light source oscillates pulsed light. 6. A mechanism for changing the illumination position of the light beam with respect to the sensor surface, a circuit configuration for adjusting a reverse voltage applied to the sensor, and a mechanism for irradiating an arbitrary position with the light beam. The method according to claim 1, comprising:
6. The sensor control device according to any one of 5. 7. A pattern on a first object plane is illuminated by pulse light from a light source means by an illumination means, and the pattern on the first object plane is illuminated on a movable object stage by a projection optical system. When projecting and exposing, a sensor is arranged on the first object surface and / or the second object surface, and the integrated exposure amount of the pulse light for irradiating the first object surface and / or the second object surface with the sensor 7. An exposure apparatus for detecting the integrated exposure amount by control means using an output value from the sensor, comprising: the sensor control device according to claim 1; An exposure apparatus wherein a voltage is dynamically controlled. 8. A device manufacturing method, comprising manufacturing a device using the exposure apparatus according to claim 7.