TWI384331B - Exposure apparatus - Google Patents

Description

Exposure equipment

The present invention relates to an exposure apparatus for exposing a substrate to radiant energy.

As micropatterning and the density of circuits increase, an exposure apparatus for fabricating a semiconductor device is required to project a circuit pattern onto a substrate surface by exposure from a mask surface, and has higher resolution. The projection resolution capability of the circuit pattern depends on the numerical aperture (NA) of the projection optical system and the exposure wavelength. In view of this, the resolution is increased by a method of increasing the NA of the projection optical system and a method of further shortening the exposure wavelength. In the method of further shortening the exposure wavelength, the wavelength of the exposure light source is shifted from the g line to the i line and from the i line to the oscillation wavelength of the excimer laser. An exposure apparatus having a pseudo-molecular laser having an oscillation wavelength of 248 nm and 193 nm has been practically used. Now, an exposure scheme using EUV (ultraviolet) light having a wavelength of 13 nm is considered as a candidate for the next generation exposure scheme.

At the same time, semiconductor device manufacturing processes are diversifying. For example, the chemical mechanical polishing (CMP) process has received a lot of attention as a planarization technique that addresses the depth of the focus of the exposure apparatus. Various structures and materials of semiconductor devices are also suggested. An example of a P high electron mobility transistor and an M high electron mobility transistor formed by combining a chemical compound such as GaAs and InP and a heterojunction bipolar transistor made of, for example, SiGe and SiGe.

With the micro-patterning of the circuit, it has been caused to accurately correct the formation Another requirement for circuit pattern reticle and projected substrate. The required correction accuracy is 1/3 of the circuit line width. For example, the required correction accuracy for the current 90 nm design is 1/3, that is, 30 nm.

Unfortunately, substrate correction often causes wafer inductive displacement of the substrate during the manufacturing process, resulting in a reduction in the performance of the semiconductor device and its manufacturing capacity. For this specification, wafer sense shifting will be referred to as "WIS." Due to the effects of planarization processes such as CMP, examples of WIS are the asymmetry of the structure of the calibration mark and the asymmetry of the shape of the resist applied to the substrate. Moreover, because of the semiconductor devices fabricated via several processes, the optical conditions of the calibration marks for each process change, resulting in a change in the amount of WIS for each process. To deal with this problem, it is necessary to prepare complex quantitative conditions for multiple corrections to determine the optimal measurement conditions for each process. For conventional substrate correction, the substrate is subjected to actual exposure under complex measurement conditions and under overlapping inspection to determine the measurement conditions for the best results of the overlap check obtained. However, this method takes a long time to determine the measurement conditions. Japanese Patent Laid-Open No. 4-32219 proposes a method of determining measurement conditions using "value obtained by quantifying the asymmetry or comparison of the calibration mark signals" as an index without overlapping inspection. In this specification, a feature value associated with calculating the measurement accuracy of the self-calibration mark signal, such as "a value obtained by quantifying the asymmetry or contrast of the calibration mark signal", will be referred to as a "feature value."

The measurement condition determination method described in Japanese Patent Laid-Open No. 4-32219 uses the average of the feature values in the surface of the substrate and their changes as indices to determine the measurement conditions. However, because the measurement error is due to the shift of the substrate Bit/magnification/rotation is generated at the actual device manufacturing location, which is difficult to correlate the conventional index with the WIS that actually poses the problem. This makes it impossible to determine the measurement conditions under WIS with some minor effects.

It is an object of the present invention to improve measurement accuracy under measurement conditions determined by no overlap inspection.

According to a first aspect of the present invention, there is provided an exposure apparatus for exposing each zone of a plurality of zones disposed on a substrate, the apparatus comprising: a measuring device configured to obtain a calibration mark formed in the zone An image signal, and measuring a position of the calibration mark based on the signal; and a processor configured to i) cause the measuring device to measure each of at least two regions formed in the complex region under a complex measurement condition a position of the calibration mark of the zone, ii) calculating, under each condition of the complex measurement condition, a characteristic value of the signal obtained with respect to each of the at least two zones, iii) relative to the complex quantity Calculating a coefficient of the conversion equation for each condition of the condition, the conversion equation converting the coordinate of the design position of the calibration mark to a value corresponding to the feature value corresponding to the design position, the conversion equation being formulated from the coordinate conversion equation, By replacing the measurement position with the characteristic value, the coordinate conversion equation converts the coordinates of the design position into values corresponding to coordinates of the measurement position corresponding to the design position, iv) based on the coefficient calculated with respect to the conditions of each of the complex number of measurement conditions, the measurement conditions are set, the measuring device measuring at the measuring conditions The position of the calibration mark.

According to a second aspect of the present invention, there is provided an exposure apparatus for exposing each of a plurality of zones disposed on a substrate, the apparatus comprising: a measuring device configured to obtain a calibration mark formed in the zone An image signal, and measuring a position of the calibration mark based on the signal; and a processor configured to i) cause the measuring device to measure each of at least two regions formed in the complex region under a complex measurement condition a position of the calibration mark of the zone, ii) calculating, under each condition of the complex measurement condition, a characteristic value of the signal obtained with respect to each of the at least two zones, iii) relative to the complex quantity Calculating a coefficient of the conversion equation for each condition of the condition, the conversion equation converting the coordinate of the design position of the calibration mark to a value corresponding to the feature value corresponding to the design position, the conversion equation being formulated from the coordinate conversion equation, By replacing the measurement position with the characteristic value, the coordinate conversion equation converts the coordinates of the design position into values corresponding to coordinates of the measurement position corresponding to the design position, A console configured to display the information relative to the calculated coefficients of the measuring conditions for each condition.

According to a third aspect of the present invention, there is provided an exposure apparatus for exposing each of a plurality of regions disposed on a substrate, the apparatus comprising: a measuring device configured to obtain a calibration mark formed in the region An image signal, and measuring a position of the calibration mark based on the signal; and a processor configured to i) cause the measurement device to be formed in the complex under a complex measurement condition The position of the calibration mark for each of at least two regions of the number zone, ii) calculating the characteristic value of the signal obtained for each of the at least two zones under each condition of the complex measurement condition And iii) calculating a coefficient of the conversion equation for each condition of the complex quantity measurement condition, the conversion equation converting the coordinate of the design position of the calibration mark to a value corresponding to the feature value corresponding to the design position, the conversion The equation is formulated from a coordinate conversion equation by replacing the measurement position with the feature value, the coordinate conversion equation converting the coordinate of the design position to a value approximately corresponding to the measurement position of the design position, and Iv) calculating a change in the coefficients on the plurality of substrates based on each condition relative to the complex quantity condition, setting a measurement condition, the measuring device measuring the position of the calibration mark under the measurement condition .

According to a fourth aspect of the present invention, there is provided an exposure apparatus for exposing each of a plurality of regions disposed on a substrate, the apparatus comprising: a measuring device configured to obtain a calibration mark formed in the region An image signal, and measuring a position of the calibration mark based on the signal; and a processor configured to i) cause the measuring device to measure each of at least two regions formed in the complex region under a complex measurement condition a position of the calibration mark of the zone, ii) calculating, under each condition of the complex measurement condition, a characteristic value of the signal obtained with respect to each of the at least two zones, iii) relative to the complex quantity Calculating a coefficient of the conversion equation for each condition of the condition, the conversion equation converting the coordinate of the design position of the calibration mark to a value corresponding to the feature value corresponding to the design position, the conversion The equation is formulated from a coordinate conversion equation by replacing the measurement position with the feature value, the coordinate conversion equation converting the coordinate of the design position to a value approximately corresponding to the measurement position of the design position, and A console configured to display a change in the coefficients on the plurality of substrates relative to each condition of the measurement condition.

According to the invention, it is possible, for example, to improve the measurement accuracy without the measurement conditions determined by the overlap check.

Further features of the present invention will become apparent from the following description of exemplary embodiments.

Embodiments of the present invention will now be described with reference to the drawings.

[First Embodiment]

Figure 1 is a schematic view showing an exposure apparatus. The exposure apparatus 1 includes, for example, a reduced projection optical system 3 that reduces and projects an image of the reticle 2, a substrate chuck 5 that holds the substrate 4, a substrate stage 6 that aligns the substrate 4 to a predetermined position, and a calibration detecting optical system 7 . A certain circuit pattern is drawn on the reticle 2. The basic pattern and the alignment mark are formed on the substrate 4 in advance. The calibration detecting optical system 7 functions as a measuring device for measuring the position of the calibration mark 15 on the substrate 4.

Fig. 11 is a flow chart for explaining the sequence of the measurement condition determining method according to the first embodiment.

In step S101, the substrate 4 is loaded onto the exposure apparatus 1. Yubu In step S102, the setting unit 10 in the CPU 9 sets the calibration measurement condition. The measurement condition may be, for example, a measurement of the illumination condition, the type of calibration mark, the number of sample shots, or the design of the sample shot. The sample photographing system calibration mark 15 is measured to determine a photographing area of the photographing configuration, which is one of a plurality of photographing areas on which the calibration mark 15 is formed on the substrate 4.

In step S103, the calibration detecting optical system 7 detects the position of the calibration mark 15 in the same shooting as that of a group of samples taken on the substrate 4. FIG. 2 is a schematic view showing main components of the calibration detecting optical system 7. Illumination light from source 71 is reflected by beam splitter 72, passes through lens 73, and illuminates alignment mark 15 on substrate 4. Light diffracted by the calibration mark 15 is returned through the beam splitter 72 and the lens 74, and is split by the beam splitter 75. The CCD sensors 76 and 77 receive the partial beams. The calibration mark 15 is enlarged by the lenses 73 and 74 until the resolution satisfies the measurement accuracy, and is imaged on the CCD sensors 76 and 77. CCD sensors 76 and 77 measure the displacement of calibration marks 15 in the X and Y directions, respectively, and have an annular spacing of 90 degrees with respect to their optical axes. Since the measurement principle is the same in the X and Y directions, only the position measurement in the X direction is explained.

Figure 3 shows an example of a calibration mark 15 for position measurement. In this example, the plurality of strip-shaped alignment marks 16 having a predetermined size in the measurement direction (X direction) and the non-measurement direction (Y direction) are set in the X direction having a predetermined interval between the continuous strips. The alignment mark 15 has a cross-sectional structure recessed by etching and is coated with a resist 17.

4 shows an example of a calibration mark signal 18 when the CCD sensor 76 has received illumination light reflected by the plurality of strip calibration marks 16. Self map The corresponding signal 18 shown in 4 detects the position of the calibration mark. The average of the calibration mark positions is finally calculated and detected as the last calibration mark position.

In step S104, the first calculating unit 12 of the CPU 9 calculates the feature value W from the signal. For example, the eigenvalue W can be calculated by the following equation: W = A × S ^a × C ^b × P ^c (1)

Among them, the S-system calibration mark signal asymmetry, the C-system comparison (S/N ratio), the P-system shape, and the constants obtained by the relationship between the characteristic values W and WIS of A, a, b, and c systems.

Regarding the "right processing region Rw" and the "left processing region Lw" of the signal shown in Fig. 5, the signal asymmetry S is defined as: S = ((σ in Rw) - (σ in Lw) / ((σ in Rw) + (σ in Lw)) (2)

Where σ is the standard deviation. The "right processing area Rw" and the "left processing area Lw" will be referred to as "right window" and "left window", respectively.

Regarding the right window Rw and the left window Lw shown in FIG. 6, when (comparison in W) = ((maximum value in W) - (minimum value in W) / ((maximum value in W) + (minimum in W) For the value)), the signal contrast C is defined as: C = ((comparison in Rw) + (comparison in Lw)) / 2 (3)

Regarding the right window Rw and the left window Lw of the signal shown in Fig. 7, the signal shape P is defined as: P={((the rightmost value in Lw)+(the leftmost value in Rw))-((the leftmost value in Lw)+(the rightmost value in Rw))}/{((in Lw The rightmost value) + (the leftmost value in Rw)) + ((the leftmost value in Lw) + (the rightmost value in Rw))} (4)

Experiments using a substrate actually subjected to WIS have confirmed that the feature value W has a correlation with WIS as shown in FIG. In other words, the calculation of the feature value W allows the operator to know the amount of WIS caused by the signal (hereinafter referred to as "the degree of influence on the WIS"". The first embodiment uses the feature value W as the index determined by the measurement condition.

The first calculating unit 12 detects the position of the calibration mark in the plural sample shooting selected from all the shooting areas on the substrate, and then calculates the feature value W while repeating the processing operations in steps S103 and S104. After detecting the position of the calibration mark in all sample shots and calculating the feature value W. The process proceeds to step S106.

In step S106, the calibration mark positions in the respective sample captures are statistically processed to implement an overall calibration that calculates a second index from the target configuration that represents the amount of displacement of the shot configuration. The second index is not based on the eigenvalue W. The second calculation unit 13 of the CPU 9 calculates the second index. For example, Japan The patent first publication No. 63-232321 describes the overall calibration.

The overall calibration calculation method will be briefly explained below. The configuration displacement can be described using the following parameters: X-direction shift Sx, Y-direction shift Sy, rotation angle θ x around the X-axis, rotation angle θ y around the Y-axis, X The magnification of the direction Bx and the magnification of the Y direction By. Assuming i is the number of shots taken, the detection value Ai taken for each sample is determined by the following equation:

The coordinate Di of the design position of the calibration mark in each sample shot is determined by the following equation:

The linear coordinate conversion D'i determined by the following equation is implemented using six parameters (Sx, Sy, θ x, θ y, Bx, By) indicating the aforementioned shooting configuration displacement amount:

Since θ x and θ y are very small, cos θ = 1 and sin θ = θ are substantially maintained. Again, because Bx 1 and By 1, θ x × Bx = θ x, θ y × By = θ y and a similar rotation angle are substantially maintained.

As shown in FIG. 9, it is assumed that the alignment mark is formed at the position W of the substrate, and the position W is shifted from the design position M by Ai. When the coordinate conversion D'i is implemented, the registration error of the calibration mark on the substrate (hereinafter referred to as "correction residual") becomes Ri. FIG. 9 is a schematic diagram showing the coordinate conversion D'i and the correction residual Ri. The corrected residual Ri is determined by the following equation: Ri = (Di + Ai) - D'i ... (8)

The overall calibration uses a least squares approach to minimize the correction residual Ri taken for each sample. That is, when the mean square V of the residual Ri is corrected, it is determined by the following equation:

Shifting, rotating, and magnifying the displacement amount (Sx, Sy, θ x, θ y, Bx, By), that is, minimizing the shooting displacement of the mean square V is determined by the following equation:

The shift, rotation, and magnification displacements (Sx, Sy, θ x, θ y, Bx, and By) are obtained by substituting the values into the detected values (xi, yi) of each sample in equations (9) and (10). And design position (Xi, Yi) to calculate. In the above manner, the shooting configuration displacement amount is calculated by the overall calibration.

In step S107, the second calculation unit 13 of the CPU 9 statistically processes the feature values W in all sample photographings to calculate a first index indicating "the amount of displacement from the photographing configuration of the target configuration". Let wx _i and wy _i be the feature values photographed for each sample, and then calculate the shooting by substituting the following equation into the overall calibrated equation (5) in step S106 and calculating equations (6) to (10) in the same manner. Configure the displacement:

The calculated shooting configuration displacement amounts are described below as (WSx, WSy, W θ x, W θ y, WBx, WBy). Calculating the shooting displacement amount makes it possible to transfer the amount of WIS that can be generated by the marking signal into the same error component, which poses a problem at the actual device manufacturing position. This makes it possible to detect the degree of influence on the WIS more accurately.

The processing operations of steps S102 to S107 are repeated while changing the measurement conditions to continue to calculate the first index under each measurement condition. The measurement conditions can be used here, for example, to calibrate the illumination conditions of the inspection optical system, the type of calibration mark, the number of sample shots, or the design of the sample shot. The setting unit 10 in the CPU 9 sets the measurement condition. Setting unit 10, first calculation sheet The element 12, the second calculation unit 13, and the decision unit 14 constitute a processor that processes the calibration mark position measurement conditions.

The control unit 11 of the CPU 9 controls, for example, the calibration detecting optical system 7 and the substrate stage 6 to measure the calibration mark under a plurality of set measurement conditions.

The processing operations of steps S102 to S107 are performed on a plurality of substrates to continuously calculate the first index of each substrate. In step S110, a change in the first index between the substrates is calculated.

The change in the first index indicating the movement, rotation, and amplification displacement between the substrates allows the prediction of the displacement component, which affects the change in WIS and the degree of influence on the WIS under each measurement condition. In other words, it is possible to use the first index as the last index for the measurement condition decision.

In step S111, the measurement condition in which the change in the first index between the substrates is the smallest is determined as the measurement condition in which the WIS has the smallest influence, and the series of measurement condition decision steps are ended. The decision unit 14 of the CPU 9 determines the optimum measurement condition.

Using the measurement condition determining process according to the first embodiment makes it possible to easily determine the optimum measurement condition, and the process error of the problem at the actual device manufacturing position is minimized under the condition without overlapping inspection.

The shape of the alignment mark according to the third embodiment is not particularly limited to the shape shown in FIG. The method of calculating the marker feature value W does not particularly limit the method of obtaining the calculation result given by the equation (1), and any value can be utilized as long as it has an association with the WIS. The selected measurement conditions are not particularly limited to the above examples. The displacement component alone can be used to give a change in the first index determined for the measurement condition, the displacement component presenting a problem at the actual device manufacturing location, for example, only the displacement component. It is also possible to use a value obtained by combining at least two of the group including the movement, the displacement component, the rotational displacement component, and the amplification displacement component, and given by the following equation:

[Second embodiment]

According to a second embodiment of the present invention, the condition determining process is performed based on the value of the first index of a substrate. The configuration and operation of the exposure apparatus are the same as in the first embodiment. Except for the measurement condition determination process, the measurement condition determination process according to the second embodiment will be explained with reference to the flowchart shown in FIG. The processing contents from the substrate to the first index calculation in steps S201 to S208 are the same as steps S101 to S108.

In the second embodiment, step S209 calculates a first index of a substrate.

In step S210, the measurement condition that the first index system is smaller is determined as the measurement condition that the WIS has the smallest influence, and the series of measurement condition determination steps is ended.

The measurement process is determined using the measurement condition according to the second embodiment so that it is possible to determine the number of substrates to be measured for the measurement condition to be reduced to one, and thus the measurement condition is shortened to determine the time.

Using only the error component can be given a first index determined for the measurement condition, the error component presenting a problem at the actual device manufacturing location, for example, only the rotational displacement component. It is also possible to use a value obtained by combining at least two of the group including the moving displacement component, the rotational displacement component, and the magnification displacement component, and given by the following equation:

[Third embodiment]

The third embodiment calculates a first index for the complex sample capture design to determine the measurement conditions based on their average. Except for the measurement condition determining process, the configuration and operation of the exposure apparatus are the same as in the first embodiment.

The measurement condition decision process according to the third embodiment will be explained with reference to the flowchart of FIG.

The processing contents carried from the substrate to the feature value W in steps S301 to S304 are the same as those calculated in steps S101 to S104. In the third embodiment, the processing operations in steps S301 to S304 are repeated for all possible sample capturing positions of the complex sample shooting design.

In step S306, the present photographing design 1 is selected from a plurality of sample photographing designs, as shown in FIG. The amount of displacement of the shooting configuration from the target configuration is calculated by the overall calibration in step S307 and based on the step S308 The calculated feature value W. The processing contents in steps S307 and S308 are the same as steps S106 and S107. The processing operations in steps S307 and S308 are repeated until the calculation of the n sample shooting design is completed. In step S310, the averaging of the displacements configured to be configured from the target configuration is calculated based on the feature values of the n sample capture designs. The processing operations in steps S301 to S310 are repeated while changing the measurement conditions and the substrate. In step S313, the change in the average of the displacement amounts of the target configurations arranged between the substrates is calculated. The operation for determining the measurement condition from the index calculated in step S314 is the same as step S111. According to the third embodiment, it is possible to improve the copying ability of the shooting configuration displacement amount and the measurement condition to determine the accuracy. As in the second embodiment, the measurement condition can be determined based on the change in the shooting configuration displacement amount and its own displacement amount.

[Fourth embodiment]

The fourth embodiment determines the accuracy by increasing the measurement condition during the WIS causing the correction of the residual component. The configuration and operation of the exposure apparatus are the same as in the first embodiment except for the measurement condition determination process. Only the measurement condition decision process according to the fourth embodiment will be explained with reference to the flowchart shown in FIG.

The processing contents from the substrate loading until the overall calibration in steps S401 to S406 are the same as steps S101 to S106. In the fourth embodiment, the residual displacement component other than the moving displacement component, the magnification displacement component, and the rotational displacement component of the photographing configuration is calculated in step S407 to obtain its 3σ, where the standard deviation of the σ-system residual displacement component. The residual displacement component of the shooting configuration is substituted into equation (11) by equation (5) and equation (6) is calculated. To Ri obtained in (10). In step S409, the measurement condition is that the residual displacement component 3σ of the photographing configuration is used as the first index, and the series measurement condition determining step is ended. Even if the WIS produces an error in the residual displacement component, it may determine the measurement condition. As in the third embodiment, the average of the plurality of sample shooting designs can be used.

[Fifth Embodiment]

The fifth embodiment shortens the measurement condition to determine the time, and improves the determination accuracy by comparing the mark signal comparison (S/N ratio) defined by the candidate equation (3) from the beginning to any measurement condition in which the C system is low. The configuration and operation of the exposure apparatus are the same as in the first embodiment except for the measurement condition determination process. The measurement condition decision process according to the fifth embodiment will be explained with reference to the flowchart shown in FIG. The processing contents from the substrate loading until the calibration mark position detection in steps S501 to S503 are the same as steps S101 to S103. In the fifth embodiment, if it is determined in step S504 that the signal comparison (S/N ratio) is lower than the set threshold, the candidate is excluded from the measurement condition at this time. This is because the signal S/N ratio decreases radially when the contrast of the mark signal becomes equal to or lower than a predetermined threshold. This results in a significant reduction in the accuracy of the correction due to noise. Furthermore, since the correction between the characteristic value W and the WIS shown in Fig. 8 becomes weak, there is a possibility that it is impossible to accurately calculate the index under the measurement condition in which the comparison is equal to or lower than the predetermined critical value. The subsequent processing operations remaining in the steps S505 to S512 as candidates for the measurement condition are the same as steps S104 to S111. According to the fifth embodiment, when there is a measurement condition in which the contrast is equal to or lower than the set threshold value, this may shorten the measurement condition determination time and improve the determination accuracy. degree. The processing operation according to step S504 of the fifth embodiment can also be applied to the second to fourth embodiments.

[Sixth embodiment]

According to a sixth embodiment of the present invention, a process of determining a reliability by using a plurality of different indices to determine a final measurement condition to increase the measurement condition is employed. The configuration and operation of the exposure apparatus are the same as in the first embodiment except for the measurement condition determination process. The measurement condition decision process according to the sixth embodiment will be explained with reference to the flowchart shown in FIG. The processing contents of the steps S601 to S610 (calculated from the change in the displacement amount of the target configuration from the substrate loading to the photographing configuration from the substrate, the change is based on the feature value) are the same as the steps S101 to S110. In the sixth embodiment, in step S611, a change in the magnification displacement component of the photographing configuration between the substrates is not based on the feature value and is calculated in step S606, and is used as an index for the measurement condition determination. In step S612, the standard deviation Ri(3σ) defined by the equation (8) and calculated for the corrected residual Ri of step S606 is calculated to obtain its average Ri(3σ) _(ave) . The calculated average Ri(3σ) _(ave) is used as an index for the measurement condition determination. In step S613, the last measurement condition determined by the weighted average of the indices calculated in steps S610 to S612 is used, and the series of measurement condition decision steps is ended. According to the sixth embodiment, it is possible to increase the measurement condition to determine the reliability as compared with only one index. The type and combination of the indices are not limited to the types and combinations using the steps S610 to S612, and the shooting configuration displacement amount as in the second embodiment can be used. The change in the shooting configuration displacement between the substrates which are not based on the feature value and used in step S611 is not particularly limited by the change in the magnification displacement component. The final measurement condition determination method in step S613 is not particularly limited by the calculation of the weighted average of the indices.

[Variation Example]

In the above embodiment, the CPU 9 automatically based on the first index of the coefficient of the equation (7) which is converted by the equation (11) instead of the coordinate of the equation (5), or based on the variation of the standard deviation of the first index such as the plurality of substrates. Set the measurement conditions. However, the change of the first index or the first index between the plurality of substrates calculated by each of the complex measurement conditions may be displayed on the display unit by the CPU 9, and based on the display information, the user of the exposure device 1 The predetermined measurement condition can be set. Therefore, the display unit can be included, for example, at the console of the CPU 9 to which the exposure apparatus 1 is connected.

[Device Manufacturing]

Next, a device manufacturing method using the above exposure apparatus will be described with reference to Figs. Figure 17 is a flow diagram of the fabrication of a device (e.g., a semiconductor wafer such as an IC or LSI, LCD or CCD). A semiconductor wafer manufacturing method will be exemplified herein.

In step S1 (circuit design), the circuit of the semiconductor device is designed. In step S2 (mask fabrication), a mask (also referred to as a prototype or a mask) is fabricated based on the designed circuit pattern. In step S3 (wafer fabrication), the wafer (also referred to as a substrate) is fabricated using a material such as tantalum. In the step S4 (wafer processing) called pretreatment, the above exposure apparatus uses a mask and a substrate by lithography The actual circuit is formed on the wafer. In a step S5 (assembly) called post-processing, the semiconductor wafer is formed using the substrate manufactured in step S4. This step includes an assembly step (cutting and bonding) and a packaging step (wafer encapsulation). In step S6 (inspection), the semiconductor device is manufactured in step S5 and is subjected to inspection such as operation confirmation test and durability test. After these steps, the semiconductor device is completed and shipped in step S7.

Figure 18 is a detailed flow chart illustrating the wafer processing of step S4. In step S11 (oxidation), the surface of the substrate is oxidized. In step S12 (CVD), an insulating film is formed on the surface of the substrate. In step S13 (electrode formation), the electrodes are formed on the substrate by deposition. In step S14 (ion implantation), ions are implanted into the substrate. In step S15 (resist process), a photosensitizer is applied to the substrate. In step S16 (exposure), the circuit pattern of the mask is transferred to the substrate by exposure using the above-described exposure apparatus. In step S17 (development), the exposed substrate is developed. Step S18 (etching), except for the developed resist image, is etched. Step S19 (resist removal), any unnecessary photoresist left after etching is removed. By repeating these steps, the multilayer structure of the circuit pattern is formed on the substrate.

While the invention has been described in detail with reference to the exemplary embodiments, it is understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation to cover all such modifications and equivalent structures and functions.

W‧‧‧ eigenvalue

Rw‧‧‧Right treatment area

Lw‧‧‧Left Processing Area

S‧‧‧Signal Asymmetry

Σ‧‧ standard deviation

C‧‧‧ comparison (S/N ratio)

P‧‧‧ shape

Sx‧‧ shift

Sy‧‧ shift

Bx‧‧‧ magnification

By‧‧‧magnification

Ai‧‧‧ detection value

θ y‧‧‧rotation angle

i‧‧‧Detection shots

θ x‧‧‧rotation angle

D' i‧‧‧ coordinate conversion

Ri‧‧‧ calibration residual

M‧‧‧Design location

Xi‧‧‧detection value

Yi‧‧‧detection value

Xi‧‧‧Design location

Yi‧‧‧Design location

V‧‧‧ mean square

Wx _i ‧‧‧ eigenvalue

Wy _i ‧‧‧ eigenvalue

WSx‧‧‧ Shooting configuration displacement

WSy‧‧‧ eigenvalue

Wx‧‧‧ eigenvalue

Wy‧‧‧ eigenvalue

WBx‧‧‧ eigenvalue

Wby‧‧‧ eigenvalue

NA‧‧‧Num. Aperture

EUV‧‧‧Ultraviolet

CMP‧‧‧Chemical polishing

WIS‧‧‧ wafer sensing shift

1‧‧‧Exposure equipment

2‧‧‧Photomask

3‧‧‧Reducing the projection optical system

4‧‧‧Substrate

5‧‧‧Substrate chuck

6‧‧‧Substrate stage

7‧‧‧ Calibration and inspection optical system

9‧‧‧CPU

10‧‧‧Setting unit

11‧‧‧Control unit

12‧‧‧First calculation unit

13‧‧‧Second calculation unit

14‧‧‧Decision unit

15‧‧‧ calibration mark

16‧‧‧Strip calibration mark

17‧‧‧Resist

18‧‧‧ Calibration mark signal

71‧‧‧Light source

72‧‧‧beam splitter

73‧‧‧ lens

74‧‧‧ lens

75‧‧‧beam splitter

76‧‧‧CCD sensor

77‧‧‧CCD sensor

Figure 1 is a schematic view showing an exposure apparatus; 2 is a schematic view showing the calibration detecting optical system 7 of FIG. 1; FIG. 3 is a schematic view showing an example of a calibration mark; FIG. 4 is a schematic view showing a calibration mark signal; FIG. 5 is a view showing a feature value; Figure 7 is a diagram showing another feature value; Figure 8 is a graph showing the relationship between the feature value and WIS; Figure 9 is a graph showing the coordinate conversion D'i and the correction residual Ri FIG. 10 is a schematic diagram showing an example of a complex sample shooting design; FIG. 11 is a flowchart illustrating a measurement condition determining process according to the first embodiment; FIG. 12 is a flowchart illustrating the measurement according to the second embodiment. FIG. 13 is a flowchart illustrating a measurement condition determination process according to the third embodiment; FIG. 14 is a flowchart illustrating a measurement condition determination process according to the fourth embodiment; FIG. 15 is a flowchart Flowchart of the measurement condition determination process of the fifth embodiment; FIG. 16 is a flow chart illustrating the measurement condition determination process according to the sixth embodiment; FIG. 17 is a flow chart for explaining the manufacture of the apparatus using the exposure apparatus; and Fig. 18 is a flow chart for explaining the details of the wafer processing in step S4 of the flowchart shown in Fig. 17.

1‧‧‧Exposure equipment

2‧‧‧Photomask

3‧‧‧Reducing the projection optical system

4‧‧‧Substrate

5‧‧‧Substrate chuck

6‧‧‧Substrate stage

7‧‧‧ Calibration and inspection optical system

9‧‧‧CPU

10‧‧‧Setting unit

11‧‧‧Control unit

12‧‧‧First calculation unit

13‧‧‧Second calculation unit

14‧‧‧Decision unit

Claims (10)

A measuring device for measuring a position of a plurality of shooting zones disposed on a substrate, the device comprising: a measuring device configured to obtain an image signal regarding a calibration mark formed by the shooting zone, and based on the signal Measuring a shift amount of the position of the calibration mark from the design position; and a processor configured to obtain a first coefficient of the first conversion equation, the first conversion equation converting the design position to approximate the design position and corresponding to a value of the sum of the shift amounts measured by the design position; and configured to obtain a position of each of the plurality of shot regions based on the first conversion equation in which the first coefficient is obtained, wherein The processor is configured to: i) cause the measuring device to obtain the image signal of the calibration mark formed by each of at least a portion of the plurality of imaging regions under each of the measurement conditions And ii) obtaining, under each condition of the complex measurement condition, a feature value of the image signal obtained by each of the at least one portion of the plurality of imaging regions, iii) related to Each number of conditional test conditions to obtain a second coefficient of the second transformation equation, which is designed to position the second transformation equation is converted into a position approximately corresponding to the design value of the characteristic of the design and location of the values, and Iv) setting the measurement condition based on the second coefficient obtained for each condition related to the complex measurement condition, the measurement device measuring the shift amount under the measurement condition. The measuring device of claim 1, wherein the processor is configured to set a condition of the complex quantity measurement condition, the second coefficient being minimum under the condition. A measuring device for measuring a position of a plurality of shooting zones disposed on a substrate, the device comprising: a measuring device configured to obtain an image signal regarding a calibration mark formed by the shooting zone, and based on the signal Measuring a shift amount of the position of the calibration mark from the design position; the processor configured to obtain a first coefficient of the first conversion equation, the first conversion equation converting the design position to approximate the design position and corresponding to the Designing a value of the sum of the shift amounts measured; and configuring, based on the first conversion equation in which the first coefficient is obtained, obtaining a position of each of the plurality of shot regions, and a display, Wherein the processor is configured to: i) cause the measuring device to obtain the calibration mark formed by each of the at least one portion of the plurality of imaging regions under each of the measurement conditions An image signal, ii) obtaining, under each condition of the complex measurement condition, a feature value of the image signal obtained by each of the at least one portion of the plurality of imaging regions Iii) obtaining, for each condition of the complex quantity measurement condition, a second coefficient of the second conversion equation, the second conversion equation converting the design position to approximate the design position and the characteristic value corresponding to the design position And a value that causes the display to display information about the second coefficient obtained for each condition of the complex measurement condition. A measuring device for measuring a position of a plurality of shooting zones disposed on a substrate, the device comprising: a measuring device configured to obtain an image signal regarding a calibration mark formed by the shooting zone, and based on the signal Measuring a position shift amount of the calibration mark from a design position; and a processor configured to obtain a first coefficient of the first conversion equation, the first conversion equation converting the design position to approximate the design position and corresponding to the a value of the sum of the shift amounts measured by the design position; and configured to obtain a position of each of the plurality of shot regions based on the first conversion equation in which the first coefficient is obtained, wherein The processor is configured to i) each of the measurement conditions under the complex measurement condition, such that the measurement device obtains the image signal of the calibration mark formed by each of the at least one portion of the plurality of imaging regions, Ii) obtaining, under each condition of the complex measurement condition, a feature value of the image signal obtained by each of the at least one portion of the plurality of imaging regions, iii) related to the Each condition number of conditions to obtain a second measured rpm Converting a second coefficient of the equation, the second conversion equation converting the design position to a value approximating a sum of the design position and the feature value corresponding to the design position, and iv) based on each of the complex measurement conditions A condition is obtained by changing the second coefficients on the plurality of substrates, and measuring conditions are set, and the measuring device measures the shift amount under the measuring conditions. The measuring device of claim 4, wherein the processor is configured to set a condition of the complex quantity measurement condition, and the change of the second coefficient is minimal under the condition. A measuring device for measuring a position of a plurality of shooting zones disposed on a substrate, the device comprising: a measuring device configured to obtain an image signal regarding a calibration mark formed by the shooting zone, and based on the signal Measuring a shift amount of the position of the calibration mark from the design position; the processor configured to obtain a first coefficient of the first conversion equation, the first conversion equation converting the design position to approximate the design position and corresponding to the Designing a value of the sum of the shift amounts measured; and configuring, based on the first conversion equation in which the first coefficient is obtained, obtaining a position of each of the plurality of shot regions, and displaying The processor is configured to i) each of the measurement conditions under the complex measurement condition, such that the measurement device obtains the image of the calibration mark formed by each of at least a portion of the plurality of imaging regions signal, Ii) obtaining, under each condition of the complex measurement condition, a feature value of the image signal obtained for each of the at least one portion of the plurality of shot regions, and iii) correlating with the complex number measurement a condition of each of the conditions to obtain a second coefficient of the second conversion equation, the second conversion equation converting the design position to a value approximating a sum of the design position and the feature value corresponding to the design position, and causing the display A change in the second coefficients obtained on the plurality of substrates obtained for each condition associated with the complex measurement condition is displayed. The measuring device according to any one of claims 1 to 6, wherein the characteristic value comprises at least one of a composition comprising a group of the following values: a value representing an asymmetry of the image signal, representing the image The value of the contrast of the signal and the value representing the shape of the image signal. The measuring device of claim 3 or 6, further comprising a console coupled to the processor, the console including the display. An exposure apparatus for exposing each of a plurality of imaging areas disposed on a substrate to radiant energy, the apparatus comprising: the measuring apparatus defined in any one of claims 1 to 6 The position of the plurality of shot regions is measured, wherein the substrate is positioned according to each of the measured positions, and the exposure system is implemented for the substrate being positioned. A device manufacturing method comprising: exposing a substrate to radiant energy using an exposure apparatus defined in claim 9; Developing the exposed substrate; and processing the developed substrate to fabricate the device.