JP6753758B2 - Polishing equipment, polishing methods and programs - Google Patents

Description

The present invention relates to a polishing apparatus for polishing a substrate such as a semiconductor wafer.

In recent years, a processing apparatus has been used to perform various processing on an object to be processed (for example, a substrate such as a semiconductor wafer or various films formed on the surface of the substrate). An example of the processing apparatus is a CMP (Chemical Mechanical Polishing) apparatus for performing a polishing treatment or the like of a processing object.

The CMP apparatus delivers the object to be treated to a polishing unit for polishing the object to be treated, a cleaning unit for cleaning and drying the object to be treated, and the polishing unit, and is cleaned by the cleaning unit. It also includes a load / unload unit that receives the processed object that has been dried (Patent Documents 1 and 2).

Patent Document 3 discloses a CMP technique for improving the accuracy of flattening a wafer surface. The invention described in Patent Document 3 is provided with a non-flat portion detector downstream of the CMP station, and is a local flattening station when the height of the non-flat portion detected by the detector is equal to or higher than a predetermined threshold value. Flatten with. At this time, the local flattening station sets a time for flattening according to the height of the detected non-flat portion, and the local flattening station performs flattening only for that time.

U.S. Patent Application Publication No. 2015/0352686 JP-A-2009-194134 U.S. Patent Application Publication No. 2013/01/22613

In the CMP technique described in Patent Document 3 described above, the non-flat portion detected by the detection unit is locally flattened for a time corresponding to the height of the non-flat portion, so that there are many non-flat portions. Moreover, when the height is high, local flattening takes a very long time. On the other hand, in the total flattening (overall polishing) using a flattening member (polishing pad, etc.) larger than the wafer surface, a plurality of non-flat parts can be polished at the same time, but the flat parts are also polished at the same time. , There is a limit to the extent to which the step between the non-flat portion and the flat portion can be eliminated.
Therefore, in view of the above background, the present invention aims to improve the throughput in the polishing apparatus.

The polishing apparatus of the present invention includes an overall polishing unit that performs overall polishing of the wafer to be processed, a local polishing unit that locally polishes the wafer, and a film thickness measuring unit that measures the film thickness of the wafer. Based on the film thickness distribution estimation unit that estimates the film thickness distribution of the wafer before polishing based on the film thickness measured by the film thickness measuring unit, and the step elimination property of the film thickness distribution and the overall polishing. A local polishing site setting unit for setting a local polishing site of the wafer on which the local polishing should be performed is provided.

With this configuration, local polishing is performed to compensate for the part that is insufficient by polishing by total polishing by determining the local polishing part in consideration of the level difference eliminating property, which is the degree to which the step of the convex portion on the wafer surface can be eliminated by total polishing. Can be done. As a result, the throughput of wafer flattening can be improved by combining the total polishing and the local polishing.

In the polishing apparatus of the present invention, a polishing head selection unit that selects a polishing head based on the size of the local polishing site, an input node for the attribute of the local polishing site, an output node for the polishing condition, and the input node. A model storage unit that stores a recipe generation model that defines the relationship with the output node, and applying the attributes of the local polishing site to the input node of the recipe generation model, the polishing of the local polishing on the local polishing site. It may be provided with a polishing recipe generation unit that generates a recipe. With this configuration, an appropriate polishing recipe can be determined according to the attributes of the local polishing site.

In the polishing apparatus of the present invention, the film thickness measuring unit measures the film thickness of the wafer after local polishing, and the recipe generation model learning unit learns the recipe generation model using the film thickness data obtained by the measurement as learning data. May be provided. With this configuration, the recipe generation model can be learned based on the film thickness distribution after local polishing.

In the polishing apparatus of the present invention, the local polishing portion may perform local polishing of the subsequent wafer by the polishing recipe used for the previously processed wafer. With this configuration, it is not necessary to determine the polishing recipe for each wafer, so that the processing speed can be increased.

In the polishing apparatus of the present invention, the local polishing portion may be arranged downstream of the whole polishing portion or may be arranged upstream. The setting of the locally polished portion in consideration of the step elimination property by the total polishing can be applied to both the case where the total polishing is performed first and the case where the partial polishing is performed first.

The polishing method of the present invention is a polishing method in which total polishing and local polishing are performed on the wafer to be processed, in which the polishing apparatus measures the film thickness of the wafer and the polishing apparatus performs before polishing. The step of estimating the film thickness distribution of the wafer based on the film thickness of the wafer, and the polishing apparatus should perform the local polishing based on the film thickness distribution and the step-eliminating property of the overall polishing. The polishing apparatus includes a step of setting a local polishing site of a wafer, a step of the polishing apparatus performing overall polishing of the wafer, and a step of the polishing apparatus performing local polishing of the wafer.

The program of the present invention is a program for controlling a polishing apparatus for performing total polishing and local polishing on a wafer to be processed, and includes a step of measuring the thickness of the wafer on the polishing apparatus. The step of estimating the film thickness distribution of the wafer based on the film thickness of the wafer before polishing, and the step elimination property of the film thickness distribution and the overall polishing of the wafer to be locally polished. The step of setting the local polishing site, the step of performing the entire polishing on the wafer, and the step of performing the local polishing on the wafer are executed.

According to the present invention, it is possible to set a locally polished portion that complements a portion that is insufficient in polishing by total polishing, shorten the time required for local polishing, and improve throughput.

It is a block diagram which shows the whole structure of the polishing apparatus which concerns on embodiment. It is a figure which shows the schematic structure of an example of a local polishing module. It is a functional block diagram which shows the function of a control device. (A) It is a contour figure which shows the film thickness distribution of the wafer before polishing estimated by the film thickness distribution estimation part. (B) It is a figure which shows the film thickness distribution assumed when it is assumed that the whole wafer is polished. It is a figure which shows the polishing head used in each step, and the movement thereof when the local polishing part is set. It is a figure which shows the example of the recipe generation model stored in the model storage part. It is a figure which shows the operation which controls local polishing by a polishing apparatus.

The polishing apparatus and polishing method according to the embodiment of the present invention will be described below with reference to the drawings. An example of a polishing apparatus described below is a CMP apparatus.
[Overall configuration of polishing equipment]
FIG. 1 is a block diagram showing an overall configuration of the polishing apparatus 100 according to the embodiment. As shown in FIG. 1, the polishing device 100 includes a local polishing module 200, an overall polishing module 300, a cleaning module 400, a drying module 500, a control device 600, and a transfer mechanism 700.

The local polishing module 200 is a module for polishing a wafer Wf using a polishing pad having a size smaller than that of a semiconductor wafer Wf (hereinafter referred to as “wafer Wf”) which is an object to be polished. The detailed configuration of the local polishing module 200 will be described later. The overall polishing module 300 is a module for polishing the wafer Wf using a polishing pad having a size larger than that of the wafer Wf to be polished. Since any known total polishing module can be used as the total polishing module 300, detailed description is not given in this specification.

The cleaning module 400 is a module for cleaning the polished wafer Wf. The cleaning module 400 can clean the wafer Wf at any timing. For example, the cleaning can be performed after each of the local polishing and the total polishing described later is completed, and the cleaning can be performed after both the local polishing and the total polishing are completed. As the cleaning module 400, any known cleaning module can be used.

The drying module 500 is a module for drying the washed wafer Wf. As the drying module 500, any known drying module can be used. The transport mechanism 700 is a mechanism for transporting the wafer Wf in the polishing apparatus 100, and transfers the wafer Wf between the local polishing module 200, the overall polishing module 300, the cleaning module 400, and the drying module 500.

The control device 600 controls the operation of each module of the polishing device 100. The control device 600 can be composed of a general-purpose computer, a dedicated computer, and the like, and includes hardware such as a storage device, an input / output device, a memory, and a CPU. The control device 600 controls the operation of the module according to the program stored in the storage device. A program that realizes the control device 600 is also included in the scope of the present invention. The transport mechanism 700 also moves the wafer Wf in and out of the polishing device 100. Any known transport mechanism 700 can be used as the transport mechanism 700.

[Local polishing module]
FIG. 2 is a diagram showing a schematic configuration of an example of a local polishing module 200 for polishing using a polishing pad 220 having a diameter smaller than that of an object to be processed. In the local polishing module 200 shown in FIG. 2, a polishing pad 220 having a diameter smaller than that of the wafer Wf, which is the object to be processed, is used.

As shown in FIG. 2, the local polishing module 200 holds a table 210 on which the wafer Wf is installed, a head 221 to which a polishing pad 220 for performing processing on the processing surface of the wafer Wf is attached, and a head 221. The arm 222, a treatment liquid supply system 240 for supplying the treatment liquid, and a conditioning unit 260 for conditioning (sharpening) the polishing pad 220 are provided. The overall operation of the local polishing module 200 is controlled by the control device 600.

The polishing pad 220 is formed of, for example, a polyurethane foam hard pad, a suede soft pad, or a sponge. As shown in FIG. 2, the diameter of the polishing pad 220 is smaller than that of the wafer Wf. Here, it is desirable that the diameter Φ of the polishing pad 220 is equal to or smaller than the region of variation in film thickness and shape to be processed. It is preferably 50 mm or less, more preferably Φ10 to 30 mm. If the region or removal amount of the wafer Wf to be locally polished is sufficiently small and the decrease in productivity is within the permissible range even if the polishing speed of the wafer Wf is small, the diameter can be set to Φ10 mm or less.

The table 210 has a mechanism for adsorbing the wafer Wf and holds the wafer Wf. In the embodiment shown in FIG. 2, the table 210 can be rotated around the rotation axis A by the drive mechanism 211. The table 210 may be caused to cause the wafer Wf to perform an angular rotation motion or a scroll motion by the drive mechanism 211, or may be stopped after being rotated at an arbitrary position on the table 210. By combining this movement with the swinging movement of the arm 222 described later, the polishing pad 220 can be moved to an arbitrary position on the wafer Wf. The polishing pad 220 is attached to the surface of the head 221 facing the wafer Wf. The head 221 can be rotated around the rotation axis B by a drive mechanism (not shown).

Further, the head 221 can press the polishing pad 220 against the processing surface of the wafer Wf by a drive mechanism (not shown), for example, an actuator such as an air cylinder or a ball screw.

The arm 222 can move the head 221 within the radius or diameter of the wafer Wf as shown by the arrow C. Further, the arm 222 can swing the head 221 to a position where the polishing pad 220 faces the conditioning portion 260.

In the present embodiment, the head 221 and the polishing pad 220 each show one example with respect to the wafer Wf, but the number of heads and polishing pads may be plural. The head 221 may have a plurality of polishing pads in the head, in which case the polishing pads may be of different sizes. Further, the local polishing module 200 may have a plurality of heads having polishing pads of different sizes. By properly using these heads or polishing pads according to the area of the wafer Wf to be polished, more efficient treatment of the wafer Wf surface becomes possible. Further, although not shown, when the local polishing module 200 has a plurality of polishing pads, the arm may be able to automatically select the optimum head.

The local polishing module 200 includes a detection head 230. A detector for detecting the state of the surface to be polished of the wafer Wf is attached to the detection head 230. The detector can be a Wet-ITM (In-line Thickness Monitor) as an example. In Wet-ITM, the detection head 230 exists on the wafer in a non-contact state, and by moving the entire surface of the wafer, the film thickness distribution (or the distribution of information related to the film thickness) formed on the wafer Wf is distributed. ) Can be detected (measured).

The detection head 230 is held by the arm 231 and by rotating the arm 231 to detect the film thickness distribution on the wafer Wf while moving a trajectory such that the detection head 230 passes through the center of the wafer Wf. ..

In addition to Wet-ITM, any type of detector can be used as the detector. For example, as a usable detection method, a non-contact type detection method such as a known eddy current type or optical type can be adopted, or a contact type detection method may be adopted.

Further, in the local polishing module 200, a detection unit 232 arranged in non-contact with the wafer Wf for detecting at least one of the notch, the orientation flat, and the laser marker formed on the wafer Wf as a reference position is provided. Alternatively, the drive mechanism 211 may be equipped with a rotation angle detection mechanism so that the table 210 can be rotated at an angle from a predetermined position.

The detection unit 232 is arranged so as not to rotate together with the table 210. By detecting the notch of the wafer Wf, the orientation flat, and at least one position of the laser marker by the detection unit 232, data such as the film thickness detected by the detection head 230 can be obtained not only in the radial position but also in the circumferential direction. It can also be associated with the position of. That is, by arranging the wafer Wf at a predetermined position on the table 210 based on the index related to the positions of the drive mechanism 211 and the wafer Wf, the film thickness on the wafer Wf or the distribution of signals related to the film thickness with respect to the reference position is distributed. Can be obtained.

Further, in the present embodiment, the detection head 230 is mounted independently of the arm 222, but the detection head 230 is attached to the arm 222, and the film thickness or the film thickness and the unevenness height are utilized by utilizing the operation of the arm 222. It may be configured to acquire a signal related to the information. Further, the polishing end point of each region to be polished may be determined based on the film thickness or the signal related to the film thickness and the height of unevenness acquired by the detection head 230.

The conditioning unit 260 is a member for conditioning the surface of the polishing pad 220. The conditioning unit 260 includes a dress table 261 and a dresser 262 installed on the dress table 261. The dress table 261 can be rotated around the rotation axis D by a drive mechanism (not shown).

The processing liquid supply system 240 includes a pure water nozzle 241 for supplying pure water (DIW) to the surface to be polished of the wafer Wf. The pure water nozzle 241 is connected to the pure water supply source 243 via the pure water pipe 242. The pure water pipe 242 is provided with an on-off valve 244 capable of opening and closing the pure water pipe 242. By controlling the opening and closing of the on-off valve 244, the control device 600 can supply pure water to the surface to be polished of the wafer Wf at an arbitrary timing.

The treatment liquid supply system 240 includes a chemical liquid nozzle 245 for supplying a chemical liquid (Chemi) to the surface to be polished of the wafer Wf. The chemical solution nozzle 245 is connected to the chemical solution supply source 247 via the chemical solution pipe 246. The chemical solution pipe 246 is provided with an on-off valve 248 capable of opening and closing the chemical solution pipe 246. By controlling the opening and closing of the on-off valve 248, the control device 600 can supply the chemical solution to the surface to be polished of the wafer Wf at an arbitrary timing.

The local polishing module 200 can selectively supply a polishing liquid such as pure water, a chemical solution, or a slurry to the surface to be polished of the wafer Wf via the arm 222, the head 221 and the polishing pad 220. It has become. That is, the branched pure water pipe 242a is branched from between the pure water supply source 243 and the on-off valve 244 in the pure water pipe 242. Further, a branch chemical solution pipe 246a is branched from between the chemical solution supply source 247 and the on-off valve 248 in the chemical solution pipe 246. The branched pure water pipe 242a, the branched chemical liquid pipe 246a, and the polishing liquid pipe 250 connected to the polishing liquid supply source 249 join the liquid supply pipe 254.

The branched pure water pipe 242a is provided with an on-off valve 251 capable of opening and closing the branched pure water pipe 242a. The branch chemical liquid pipe 246a is provided with an on-off valve 252 capable of opening and closing the branch chemical liquid pipe 246a. The polishing liquid pipe 250 is provided with an on-off valve 253 capable of opening and closing the polishing liquid pipe 250. The polishing solution may be configured so that it can be supplied onto the wafer Wf from the outside of the head 221 in the same manner as the pure water and the chemical solution.

The first end of the liquid supply pipe 254 is connected to three systems of a branch pure water pipe 242a, a branch chemical liquid pipe 246a, and a polishing liquid pipe 250. The liquid supply pipe 254 extends through the inside of the arm 222, the center of the head 221 and the center of the polishing pad 220. The second end of the liquid supply pipe 254 opens toward the surface to be polished of the wafer Wf. By controlling the opening and closing of the on-off valve 251 and the on-off valve 252, and the on-off valve 253, the control device 600 can be used as a polishing liquid such as pure water, a chemical solution, or a slurry on the surface to be polished of the wafer Wf at an arbitrary timing. A mixture of one or any combination thereof can be supplied. The overall configuration of the polishing apparatus 100 has been described above. Subsequently, the function of the control device 600 of the present embodiment that controls the local polishing module 200 will be described.

[Control device]
FIG. 3 is a functional block diagram showing the functions of the control device 600. In this specification, the functions of the control device 600 other than the function of controlling the local polishing module 200 will not be described. The control device 600 includes a film thickness distribution estimation unit 601, a communication unit 602, and a local polishing control unit 1 that controls the local polishing module 200. The communication unit 602 has a function of communicating with an apparatus that performs an etching process or the like upstream, and receives data such as an etching pattern performed upstream.

The film thickness distribution estimation unit 601 is connected to the film thickness measuring unit 800 that measures the film thickness of the wafer to be processed. The film thickness measuring unit 800 may be provided in the partial polishing module 200, may be provided in the total polishing module 300, or may be provided in other modules. Specific examples of the film thickness measuring unit 800 are, for example, the detection head 230 and the detection unit 232 described above.

The film thickness distribution estimation unit 601 has a function of estimating the film thickness distribution of the wafer to be polished. The film thickness distribution estimation unit 601 estimates the film thickness distribution of the wafer based on the data of the film thickness measurement result of the wafer received from the film thickness measurement unit 800 and the etching pattern data received by the communication unit 602. Since the unevenness of the surface of the wafer is affected by the wiring pattern of the lower layer, the film thickness of the portion not measured by the film thickness measuring unit 800 can be accurately complemented by using the etching pattern data. Since the film thickness distribution estimation unit 601 estimates the film thickness distribution of the wafer in this way, the film thickness measurement unit 800 does not need to perform fine measurement, and the time required for the film thickness measurement can be shortened. In the present embodiment, an example of estimating the film thickness distribution using the etching pattern data used in the upstream etching step is described, but it is not essential to use the etching pattern data, and the film is not essential. The thickness distribution estimation unit 601 may be configured to estimate the film thickness distribution only from the data of the measurement result of the film thickness of the wafer.

The local polishing control unit 1 has a configuration for generating a polishing recipe for local polishing, which is a recipe stored in the local polishing site setting unit 11, the polishing head selection unit 12, the polishing recipe generation unit 13, and the storage unit 18. It has a generative model.

FIG. 4A is a contour diagram showing the film thickness distribution of the wafer before polishing estimated by the film thickness distribution estimation unit 601. In FIG. 4A, the film thickness distribution is represented by contour lines, and the film thickness distribution is represented by contour lines having heights of 10, 15, and 20. In the example shown in FIG. 4A, a region r1 surrounded by contour lines at height 10, a region r2 surrounded by contour lines at height 15, and two regions r3 surrounded by contour lines at height 20 It has r4 and.

In FIG. 4A, the contour diagram is represented by three types of contour lines, but the number of stages to be divided can be appropriately set. Once the number of divisions is determined, the film thickness distribution estimation unit 601 can determine which height of the contour line to draw by (maximum height-minimum low) / number of divisions.

The local polishing site setting unit 11 has a function of setting the local polishing site based on the film thickness distribution estimated by the film thickness distribution estimation unit 601 and the step elimination property by the total polishing. FIG. 4B is a diagram for explaining the step-eliminating property by the total polishing, and shows the film thickness distribution assumed when the wafer having the film thickness distribution of FIG. 4A is assumed to be totally polished. It is a figure. It can be obtained by simulating the polishing amount based on the polishing conditions of the total polishing.

In the example shown in FIG. 4B, the film thickness distribution in consideration of the step elimination property has a region r5 surrounded by contour lines of height 5 and regions r6 and r7 surrounded by contour lines of height 10. doing. In this example, the regions r3 and r4 shown in FIG. 4A are polished to the same height as the contour lines of height 10 by total polishing to become one region represented by contour lines 10 (heights 10 to 14). Is shown.

The local polishing site setting unit 11 sets the local polishing site based on the film thickness distribution when it is assumed that the entire polishing shown in FIG. 4B is performed. In this example, each of the regions r5 to r7 is set as a local polishing site.

FIG. 5 is a diagram showing a polishing head used in each step and its movement when a local polishing site of regions r5 to r7 is set. In this example, it takes 3 steps to locally polish the locally polished portion of the regions r5 to r7.

The polishing head selection unit 12 selects the polishing head based on the size of the locally polished portion. In step 1 and step 2, a polishing head having a size that just covers the local polishing sites r7 and r6 in each step is selected. In step 3, since there is no polishing head that covers the local polishing portion r5, a polishing head having a size capable of efficiently performing local polishing is selected. Specifically, a rectangular scan area (vertical length H × horizontal length W) that covers the local polishing portion r5 is set, and the scanning area is scanned (scanned) by the polishing head to perform local polishing of the region r5.

The polishing recipe generation unit 13 has a function of obtaining a polishing recipe for polishing a locally polished portion. First, the polishing recipe generation unit 13 obtains a range in which the polishing head covers the locally polished portion. Explaining with reference to FIG. 5, in step 1 and step 2, the polishing head completely covers the local polishing portion. In such a case, the position of the polishing head at the time of polishing may be obtained. In step 3, since the locally polished portion is larger than the polishing head, the vertically long H and the horizontally long W of the rectangular scan area covering the locally polished portion are obtained. Then, the locus of the polishing head that scans the entire scan area in a short time is obtained.

Next, the polishing recipe generation unit 13 obtains other conditions for performing local polishing. Specifically, the polishing recipe generation unit 13 obtains a polishing recipe according to the attribute of the local polishing site by using the recipe generation model read from the storage unit 18. In this embodiment, a neural network model is used as the recipe generation model.

FIG. 6 is a diagram showing an example of a recipe generation model stored in the model storage unit 18. The recipe generation model has attributes such as a local polishing site as an input node, and has a condition for polishing as an output node, that is, a polishing recipe. The input nodes include the average film thickness of the locally polished portion, the vertically and horizontally long scan areas, and the head type node. The output node has nodes of scan speed, number of scans, pressing pressure of polishing pad, and polishing time. When it is not necessary to scan the polishing head as in steps 1 and 2 of FIG. 5, it is assumed that there is no input node for the vertical and horizontal attributes of the scan area and an output node for the scan speed and the number of scans. deal with.

The recipe generation model shown in FIG. 6 is an example, and the input node and the output node of the model for obtaining the polishing recipe are not limited to those illustrated in FIG. For example, the output node may have a node such as the rotation speed of the polishing head or the supply speed of the slurry. Further, the intermediate node between the input node and the output node may have a plurality of layers instead of one layer.

The polishing recipe generation unit 13 applies the average film thickness of the local polishing area, the vertical and horizontal attributes of the scan area set by the local polishing area setting unit 11 to the input node, and selects them by the polishing head selection unit 12. Apply the polished head and find the value of the output node. As a result, the polishing recipe generation unit 13 can obtain a polishing recipe, that is, various conditions for performing local polishing.

In the present embodiment, a neural network model has been described as an example as a recipe generation model for obtaining a polishing recipe, but the model for obtaining a polishing recipe is not limited to the neural network model, but is a decision tree model or a Bayesian network. A model can also be used.

The explanation will be continued by returning to FIG. The local polishing control unit 1 includes a simulation unit 14 for verifying the polishing recipe generated by the polishing recipe generation unit 13. The simulation unit 14 simulates the film thickness distribution when the wafer is locally polished according to the polishing recipe.

The simulation unit 14 reads out the simulation model stored in the storage unit 18 and applies the local polishing conditions to the simulation model to calculate the film thickness distribution and the throughput after the local polishing. As a result, when the film thickness distribution and the throughput of the wafer after the local polishing satisfy the predetermined specifications, the simulation unit 14 determines that the generated polishing recipe is OK. As a result of the simulation, if the film thickness distribution or the throughput does not satisfy the predetermined specifications, the simulation unit 14 determines that the polishing recipe is NG.

The polishing recipe transmission unit 15 has a function of transmitting the data of the polishing recipe determined to be OK in the verification by the simulation unit 14 to the local polishing module 200. When the local polishing module 200 receives the polishing recipe transmitted from the local polishing control unit 1 by the polishing recipe receiving unit 271, the local polishing module 200 drives various driving units 270 according to the received polishing recipe to perform local polishing.

The various drive units 270 are drive units for driving the local polishing device 100 described with reference to FIG. 2, for example, a drive mechanism 211 for the table 210, a drive mechanism for the arm 222, and a rotation drive mechanism for rotating the polishing pad 220. , An actuator that presses the polishing pad 220 against the wafer, an on-off valve 244, 248, 251 to 253 of the processing liquid supply system 240, and the like.

The local polishing module 200 measures the film thickness after locally polishing the wafer according to the polishing recipe, and transmits the measured film thickness data from the actual polishing data transmission unit 272 to the local polishing control unit 1. .. When the local polishing control unit 1 receives the film thickness data transmitted from the local polishing module 200, the learning unit 16 learns the recipe generation model using the received film thickness data as a teacher signal. As a result, the accuracy of the recipe generation model can be improved based on the actual polishing data.

Further, the local polishing control unit 1 has an output unit 17. The output unit 17 is configured by, for example, a display means such as a display. The local polishing control unit 1 outputs, for example, the simulation result by the simulation unit 14 from the output unit 17. As a result, when the simulation result is NG, it is possible to grasp which part of the wafer is insufficiently polished, or how much more polishing is required up to a predetermined specification range. This makes it possible to modify the polishing recipe and adjust the neural network model for obtaining the polishing recipe.

FIG. 7 is a diagram showing an operation of controlling local polishing by the polishing device 100. The control device 600 receives the data of the etching pattern of the wafer to be locally polished via the communication unit 602 (S10). The film thickness measuring unit 800 measures the film thickness of the wafer to be polished (S11), and the film thickness distribution estimation unit 601 estimates the film thickness distribution based on the film thickness measurement result and the etching pattern, and generates a contour diagram. (S12). Subsequently, the local polishing site setting unit 11 estimates the film thickness distribution after the step is eliminated when the entire polishing is performed based on the film thickness distribution before the wafer processing (S13). The local polishing site setting unit 11 sets the local polishing site based on the estimated film thickness distribution (S14).

Subsequently, the local polishing control unit 1 selects a polishing head for polishing each local polishing site based on the size of the local polishing site (S15). Next, the local polishing control unit 1 reads a recipe generation model for recipe generation from the storage unit 18, and applies the attributes of the local polishing site and the type of polishing head to the recipe generation model to obtain the local polishing site. A polishing recipe for polishing is generated (S16).

Next, the local polishing control unit 1 simulates the film thickness distribution when the locally polished portion is polished using the generated polishing recipe and further the entire polishing is performed (S17). As a result of this simulation, it is determined whether or not the throughput and the film thickness after polishing satisfy the criteria of surface uniformity (S18). As a result, when it is determined that the criteria are satisfied (YES in S18), the polishing recipe is stored in the storage unit 18, and the polishing recipe is transmitted to the local polishing module 200 to actually polish the wafer (S20).

As a result of the simulation, if the criteria of throughput and surface uniformity are not satisfied (NO in S18), a polishing recipe is manually generated (S19), and actual polishing is performed according to the generated polishing recipe (S20). When processing the same type of wafer, it is not necessary to generate a polishing recipe every time, and local polishing is performed using the previously generated polishing recipe. As a result, the time for generating the polishing recipe can be omitted, so that the throughput can be increased.

In the polishing apparatus of the present embodiment, when the local polishing part setting unit 11 sets the local polishing part, the local polishing part is set in consideration of the step elimination property when the whole polishing is performed, so that the whole polishing is performed. And local polishing can be combined to improve throughput.

Although the polishing apparatus and the polishing method of the present invention have been described in detail with reference to the embodiments, the polishing apparatus of the present invention is not limited to the above-described embodiments. In the above-described embodiment, the film thickness distribution estimation unit 601 estimates the film thickness distribution based on the measurement result by the film thickness measurement unit 800, but the film thickness distribution estimation unit 601 uses the film thickness measurement result. The film thickness distribution may be estimated based on the information of the previous step performed on the wafer to be processed without using. As information on the previous process, for example, in addition to the etching pattern mentioned in the above embodiment, the characteristics of the film-attached machine, the layout of the wiring pattern, the CVD conditions (gas flow rate, temperature), the operating conditions of the plating apparatus, etc. There is.

The present invention is useful as a polishing apparatus or the like for polishing a substrate such as a semiconductor wafer.

1 Local polishing control unit 11 Local polishing site setting unit 12 Polishing head selection unit 13 Polishing recipe generation unit 14 Simulation unit 15 Polishing recipe transmission unit 16 Learning unit 17 Output unit 18 Storage unit 601 Film thickness distribution estimation unit 602 Communication unit 800 Film thickness Measuring unit

Claims (8)

An overall polishing part that performs overall polishing of the wafer to be processed,
A local polishing part that locally polishes the wafer and
A film thickness measuring unit that measures the film thickness of the wafer,
A film thickness distribution estimation unit that estimates the film thickness distribution of the wafer before polishing based on the film thickness measured by the film thickness measurement unit, and a film thickness distribution estimation unit.
Local polishing site setting that obtains the film thickness distribution when it is assumed that the entire polishing is performed on the film thickness distribution, and sets the local polishing site of the wafer to which the local polishing should be performed based on the obtained film thickness distribution. Department and
A polishing device equipped with. A polishing head selection unit that selects a polishing head based on the size of the locally polished portion,
Input node attributes of the local polishing site, and an output node Migaku Ken conditions, and the model storage unit that stores a recipe creation model defining the relationship between said input node and said output node,
Applying the attribute of the local polishing site to said input node of said recipe generation model, and the polishing recipe generation unit for generating a Migaku Ken recipe local polishing of the local polishing site,
The polishing apparatus according to claim 1. The second aspect of claim 2 includes a recipe generation model learning unit that measures the film thickness of the wafer after local polishing with the film thickness measuring unit and learns the recipe generation model using the film thickness data obtained by the measurement as training data. Polishing equipment. The polishing apparatus according to any one of claims 1 to 3, wherein the local polishing unit performs local polishing of a subsequent wafer in the polishing recipe used for the previously processed wafer. The polishing apparatus according to any one of claims 1 to 4, wherein the local polishing portion is located downstream of the overall polishing portion. The polishing apparatus according to any one of claims 1 to 4, wherein the local polishing portion is located upstream of the overall polishing portion. It is a polishing method that performs total polishing and local polishing on the wafer to be processed.
The step in which the polishing device measures the film thickness of the wafer,
A step in which the polishing apparatus estimates the film thickness distribution of the wafer based on the film thickness of the wafer before polishing.
The film thickness distribution when it is assumed that the polishing apparatus performs overall polishing with respect to the film thickness distribution is obtained, and the local polishing portion of the wafer to be locally polished is set based on the obtained film thickness distribution. Steps to do and
The step that the polishing apparatus performs the whole polishing on the wafer,
A step in which the polishing apparatus locally polishes the wafer,
Polishing method including. A program for controlling a polishing apparatus for performing total polishing and local polishing on a wafer to be processed.
The step of measuring the film thickness of the wafer and
A step of estimating the film thickness distribution of the wafer based on the film thickness of the wafer before polishing, and
A step of obtaining a film thickness distribution when it is assumed that the entire film thickness is polished with respect to the film thickness distribution, and setting a locally polished portion of the wafer to be locally polished based on the obtained film thickness distribution .
The step of polishing the entire wafer and
The step of locally polishing the wafer and
A program that executes.

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