JP2001138218A - Cmp machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect any operational abnormalities of an abrasive head and the possibility of generation thereof at an early stage without any checking work by an operator. SOLUTION: The reference data in a normal operation to be identified from the relationship between the position of the abrasive head 6 and the elapsed time after the movement is started is stored in a non-volatile memory 21 as a normal value storing means in advance. A position detecting means 14 is disposed on a CMP machine 1, the present position of the abrasive head 6 is detected via the position detecting means 14 during the operation of the abrasive process, and the data to express the relationship between the elapsed time and the head position is temporarily stored. Using this data, the measured data 28a of the same level as the reference data 21a is obtained, and the presence or absence of an abnormal operation of the abrasive head 6 is automatically judged by comparing the measured data 28a with the reference data 21a by an abnormality judging means 26a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a CMP machine, and more particularly, to an addition of a function for detecting an abnormality of a polishing head.

[0002]

2. Description of the Related Art With the recent development of LSI technology, multilayering and miniaturization of LSI are required. Since the depth of focus of the stepper is not enough due to the multilayering, flattening the wafer surface has become an important issue.

[0003] What performs this flattening is a CMP processing machine (chemical mechanical polishing apparatus). In a CMP processing machine, at a position where a wafer is loaded or unloaded, a wafer to be polished is attracted to the polishing head by up, down, left and right operations of the polishing head, and the polishing head is moved onto a polishing table, and the polishing head and A polishing operation for a predetermined time is performed by pressing the wafer against a polishing pad on the polishing table while rotating the polishing table.

Further, a wafer that has been polished by one polishing table may be further polished by another polishing table as needed. In such a case, the polishing head is moved to another polishing table while holding the wafer. Move to the polishing table,
The polishing operation is repeated in the same manner as described above.

[0005]

However, as the polishing operation is repeated, a cylinder operation, a linear motion guide, and a rotation guide, which are driving sources for the vertical movement of the polishing head, are caused by structural problems related to the head feed mechanism. May slow down. In this case, the pressing force for pressing the wafer against the polishing table is insufficient, so that a polishing abnormality occurs, and the processing of the product lot is interrupted.

Conventionally, in such a case, when the occurrence of a polishing abnormality in the wafer is detected and the vertical movement of the polishing head is estimated, the failure recovery work of the CMP machine, the cylinder replacement work, and the like have been performed. In addition, the operation is stopped during the operation of the CMP processing machine, and there is a problem that productivity is reduced.

[0007] Further, since the operation of recovering the failure of the CMP machine and the operation of replacing the cylinder have been performed after actually confirming the occurrence of the polishing abnormality, if the abnormality detection is delayed, it is necessary to perform the operation before the abnormality detection. The polished wafer may also have an abnormality, which may require a product confirmation operation for the previous lot, and also has the disadvantage of complicating the operation. Further, since it is difficult to estimate the frequency and timing of occurrence of an abnormality in a cylinder or the like serving as a drive source, it is difficult to arrange replacement parts.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned disadvantages of the prior art and detect an abnormal operation of the polishing head or the possibility of the occurrence at an early stage without requiring an operator to confirm the operation. It is an object of the present invention to provide a CMP machine capable of performing the above.

[0009]

According to the present invention, there is provided a polishing table on which a polishing pad is mounted, a polishing head for holding and rotating a wafer, and a rotating surface of the polishing head being perpendicular to a normal direction of the polishing table. And a head feed mechanism for moving the polishing head in the normal direction with respect to the turntable in a state, wherein the position of the polishing head is detected in order to achieve the above object. Means, normal value storage means for storing reference data corresponding to normal operation of the head feed mechanism which can be specified from the relationship between the position of the polishing head and the elapsed time after the start of movement, and detecting the position when the head feed mechanism operates. Means for obtaining actual measurement data of the same type as the reference data based on the position data detected in time series, and obtaining the actual measurement data and the reference data stored in the normal value storage means. Comparing the door has a configuration in which the difference is characterized by comprising an abnormality judging means for outputting an abnormality detection signal when it exceeds a predetermined value.

As described above, the actually measured data obtained during the operation of the head feed mechanism and the reference data stored in the normal value storage means (data corresponding to the normal operation of the head feed mechanism).
Is compared with the abnormality determination means of the CMP machine itself to determine the presence / absence of an operation abnormality, so that the presence / absence of an operation abnormality of the polishing head can be quantitatively determined without performing an operation of confirming an abnormality by an operator. Can be determined. Further, by adjusting a predetermined value serving as a criterion for abnormality determination, it is also possible to detect a slight operation abnormality that does not cause an abnormality in the actual polishing work, and it is possible that a polishing abnormality may occur in the future. Can be predicted in advance. In this case, when the production amount is small, early maintenance work is performed when the CMP processing machine is in a halt state, such as lot separation or periodic maintenance,
The occurrence of abnormalities during steady operation can be prevented beforehand, leading to an improvement in productivity.

The reference data stored in the normal value storage means may be any data as long as it can be obtained by the detection means provided in the CMP machine.

For example, when the CMP machine is provided with position detecting means for detecting the moving position of the polishing head, the reference data stored in the normal value storage means is a polishing data corresponding to a normal operation of the head feed mechanism. The value of the movement stroke of the head can be used.

Further, if the CMP machine has position detecting means for detecting the moving position of the polishing head in time series, the normal data of the head feed mechanism is used as the reference data stored in the normal value storing means. Polishing head movement time corresponding to operation, polishing head position change pattern, polishing head average movement speed, polishing head speed change pattern, polishing head movement speed, polishing head movement start time, polishing head movement The relationship between the elapsed time after the start and the movement position can be used.

Further, the above-described moving stroke, required moving time, position change pattern, average moving speed of the polishing head,
All the components of the speed change pattern of the polishing head, the moving speed of the polishing head, the time required to start the movement of the polishing head, the elapsed time after the start of the movement of the polishing head, and the abnormality determining means relating to the moving position are combined. When the output number of the abnormality detection signal from the abnormality determination means exceeds a set value, an operation abnormality comprehensive determination means for outputting a final abnormality detection signal is provided so as to comprehensively determine the presence or absence of an abnormal operation of the polishing head. It is also possible to configure.

According to this configuration, the presence or absence of the abnormal operation of the polishing head is comprehensively determined based on various conditions, so that the reliability of the determination result of the occurrence of the abnormality is further enhanced.

Further, a structure is provided in which a load cup for mounting a wafer to be polished is provided, and the polishing head is reciprocated between the load cup and the polishing table by the cooperative operation of the horizontal feed mechanism and the head feed mechanism. In the case of a CMP processing machine having a polishing head, reference data for a load cup position to be used when the polishing head is positioned on the load cup and a reference data for a polishing table position to be used when the polishing head is positioned on the polishing table. A normal value storage means storing reference data is provided, and the abnormality determination means is provided with a reference data for a load cup position or a polishing table position from the normal value storage means in accordance with a determination result of the head position determination means. And a reference data selection function for selecting one of the reference data.

According to this configuration, in addition to the abnormal operation of the polishing head pressing mechanism which affects the polishing amount, the abnormal operation when the polishing head mounts the wafer to be polished at the predetermined position can be detected. Become.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing a main part of a CMP processing machine 1 according to one embodiment to which the present invention is applied.

A processing machine main body 2 constituting an actual working section of the CMP processing machine 1 includes a base 3, a polishing table 4 provided on the base 3, and a polishing pad 5 attached to the polishing table 4. And a polishing head 6 disposed on a polishing table 4 via a guide 10 mounted on a column (not shown) provided integrally with the base portion 3 and a wafer 9 to be polished. Road cup 7
Etc.

The polishing table 4 is driven to rotate in the direction of arrow α in FIG. 1 by a drive mechanism (not shown), and the polishing pad 5 mounted on the polishing table 4 also rotates integrally with the polishing table 4. ing. Then, the polishing pad 8 is filled with a polishing liquid 8 supplied through a nozzle (not shown) or the like, and the wafer 9 rotated and driven by the polishing head 6 is subjected to chemical mechanical polishing.

The polishing head 6 comprises a head main body 6a and a chuck section 6b. The chuck section 6b is driven by a rotation driving mechanism (not shown) provided in the head main body 6a.
Is rotationally driven in the direction of arrow β in FIG. Further, the chuck portion 6b has a suction function using vacuum evacuation or the like, and stably holds the wafer 9 to be polished.

The polishing head 6 can be fed in the Z-axis direction in FIG. 1 along a guide 10 by a head feed mechanism 11 composed of a cylinder. The guide 10, the head feed mechanism 11, and the polishing head 6 are integrated with each other by a horizontal feed mechanism (not shown) provided between the guide 10 and the guide 10, that is, the direction of the X axis in FIG. It is designed to be moved back and forth between the two.

The controller 12 controls the rotation of the polishing table 4 and the polishing head 6, the horizontal movement of the polishing head 6 by the above-described horizontal feed mechanism, and the vertical movement of the polishing head 6 by the head feed mechanism 11 as a whole. The vertical movement of the polishing head 6 is performed by controlling ON / OFF of a cylinder constituting the head feed mechanism 11 via the pressure control unit 13.

That is, by outputting an ON command from the control device 12 to the pressure control unit 13, air is supplied to the cylinder constituting the head feed mechanism 11 to lower the polishing head 6, and the control device 12 performs pressure control. When the command to the unit 13 is turned off, the supply of air to the above-described cylinder is stopped, and the cylinder constituting the head feed mechanism 11 operates in the reverse direction due to the force of the automatic return spring or switching of the port, etc. 6 rises.

The above configuration is the same as that of the conventional CMP machine. The basic one-cycle operation is performed by holding the polishing head 6 at the standby position at the upper end of the guide 10 and loading the polishing head 6 into the load cup. 7; a step of lowering the polishing head 6 to suck the unprocessed wafer 9 on the load cup 7 by the chuck portion 6b; and a step of returning the polishing head 6 to the standby position at the upper end to move the polishing head 6 back. FIG. 1 shows a step of positioning on the polishing table 4 and an actual polishing operation by starting the rotation of the chuck portion 6b to lower the polishing head 6 and pressing the unprocessed wafer 9 against the polishing pad 5 for a predetermined time. And the step of returning the polishing head 6 to the standby position at the upper end to stop the rotation of the chuck portion 6b. Thereafter, the polishing head 6 is separated if necessary. Or it is positioned on the polishing table performs the same polishing operations, or operations such as to release the suction of the chuck portion 6b back on the load cup 7 to recover the processed wafer 9 is carried out. In addition, in the step of the polishing operation shown in FIG. 1, in addition to the rotation of the chuck portion 6b and the rotation of the polishing table 4, the horizontal swinging operation of the polishing head 6 by the above-described horizontal feed mechanism is performed. Improvements in polishing efficiency and planarization of the polished surface have been achieved.

In this embodiment, in addition to the above-described structure of the prior art, the position detecting means 14 for detecting the vertical movement position of the polishing head 6 and whether the polishing head 6 is located on the load cup 7 side or not. A head position determination means 15 for determining whether the head is located on the polishing table 4 side is mounted on the processing machine main body 2.
Is provided with a control signal detection sensor 16 for detecting the ON / OFF state of a command from the CMP control device 12.

The signals from the position detecting means 14, the head position determining means 15, and the control signal detecting sensor 16 are AD signals.
An abnormality determination unit 1 which is digitally converted via the IO board 17 and includes a normal value storage unit and an abnormality determination unit
8 is input.

As shown in FIG. 2, the abnormality judging unit 18 includes a CPU 19 as arithmetic means, a ROM 20 storing an operation program thereof, a RAM 22 used for temporarily storing arithmetic data, an AD / IO board 17, and the like. Input / output circuit 23, AD /
It comprises a buffer 24 for temporarily storing data input via the IO board 17, a non-volatile memory 21 functioning as a normal value storage means, and the like.

The alarm unit 25 includes a warning light such as a patrol light and a warning sound generator such as a buzzer, and is controlled to be ON / OFF by the abnormality determination unit 18 via the AD / IO board 17. It has become.

FIG. 3 is a conceptual diagram showing an example of the storage state of the reference data in the nonvolatile memory 21 as the normal value storage means. In the present embodiment, the reference data is used for judging an abnormality in the vertical movement of the polishing head 6. The following eight types of reference data are prepared in advance.

First, the moving stroke 21a is
This is the amount of movement of the polishing head 6 when the polishing head 6 that moves up and down along the line 0 actually starts descending from the upper end position and descends to the position where the pressing of the wafer 9 is started. As described above, the polishing head 6 moves up and down in two modes, that is, when the wafer 9 is polished on the polishing table 4 and when the unprocessed wafer 9 is sucked on the load cup 7. , Two types of reference data are prepared in advance, one for the polishing table position and the other for the load cup position, in accordance with each operation mode. The value of the movement stroke serving as the reference data may be set in accordance with design data, or may be set by actually operating the CMP machine and measuring the movement stroke during normal operation.

The required moving time 21b is the required moving time of the polishing head 6 when the above-described moving stroke is achieved. As described above, two types, one for the polishing table position and one for the load cup position, are prepared in advance, and the values may be in accordance with the design data, or the actual value of the CMP processing machine may be normal. The time required for movement when the operation is performed may be adopted.

The position change pattern 21c is a series of data indicating the relationship between the elapsed time after the start of the lowering of the polishing head 6 and the current position of the polishing head 6 at that time. As described above, two types, one for the polishing table position and one for the load cup position, are prepared in advance. The value may be in accordance with design data, or may be used by sampling position data when the CMP processing machine normally operates normally.

The average moving speed 21d is an average during the period when the polishing head 6 moving up and down along the guide 10 actually starts descending from the upper end position and then descends to the position where the pressing of the wafer 9 is started. The moving speed. As described above, two types, one for the polishing table position and one for the load cup position, are prepared in advance, and the values may be in accordance with the design data, or the actual value of the CMP processing machine may be normal. May be obtained from the relationship between the movement stroke and the required movement time when the operation is performed.

The speed change pattern 21e is a series of data indicating the relationship between the elapsed time after the start of the lowering of the polishing head 6 and the moving speed of the polishing head 6 at that time. As described above, two types, one for the polishing table position and one for the load cup position, are prepared in advance, and the values may be in accordance with the design data, or the actual value of the CMP processing machine may be normal. The position data at the time of operation may be sampled, the moving speed for one cycle may be obtained from the relationship between the sampling cycle and the position data, and the speed change pattern may be set in correspondence with the elapsed time at each sampling. .

The moving speed 21f is an intermediate moving speed in a range in which the descending speed of the polishing head 6 can be regarded as normal. As described above, two types, one for the polishing table position and one for the load cup position, are prepared in advance.

The required moving start time 21g is a value of a time lag required from when the application of air pressure to the cylinder constituting the head feed mechanism 11 is started to when the polishing head 6 actually starts descending. . This reference data is different from each of the above-described reference data, and is a value that only makes sense when the polishing head 6 starts descending.
Presses the wafer 9 for a polishing operation (in this case, a large reaction force is applied at the final stage of the descent), or approaches the wafer 9 to mount a new wafer 9 (in this case, the final descent of the descent). (There is no particular reaction force at each stage.) Since there is no influence of the difference in operation type, there is no problem even if the one for the polishing table position and the one for the load cup position are used in common.

The relationship 21h between the elapsed time after the start of the movement and the movement position is basically based on the position change pattern 21 described above.
Similar to c, a series of data indicating the relationship between the elapsed time after the start of lowering of the polishing head 6 and the current position of the polishing head 6 at that time. However, in the case of the position change pattern 21c described above, the relationship between the elapsed time after the start of the movement and the movement position is grasped as a continuous series of functions, and an abnormality is determined depending on whether the tendency of the actual measurement data as a whole is close to the pattern. While the presence or absence is determined, the relationship 21h between the elapsed time after the start of movement and the movement position referred to here is determined by comparing each of the movement positions at each elapsed time individually to determine whether there is an abnormality. And there is a difference in how data is handled. As described above, two types, one for the polishing table position and one for the load cup position, are prepared in advance. The value may be in accordance with design data, or may be used by sampling position data when the CMP processing machine normally operates normally.

FIG. 4 shows the CPU 1 of the abnormality determination unit 18.
Abnormality determination means 26 constituted by the ROM 9 and the ROM 20
It is a functional block diagram schematically showing an example of the processing of FIG. Here, as an example, the movement stroke 21 of the polishing head 6 is
The description will be made by taking an example of the abnormality determination unit 26a using the reference data a as the reference data.
Even when 1h is used, the overall processing flow is almost the same.

First, based on a signal from the head position detecting means 15, the reference data selecting section 30a in the abnormality determining means 26a determines whether the polishing head 6 is located on the polishing table 4 or the load cup 7. Is determined. When the polishing head 6 is located on the polishing table 4, the reference data for the polishing table position is read out of the reference data of the movement stroke 21a stored in the non-volatile memory 21 as the normal value storage means. This is set in the comparison unit 29a in the abnormality determination unit 26a. When the polishing head 6 is located on the load cup 7, the reference data for the load cup position among the reference data of the movement stroke 21a stored in the nonvolatile memory 21 is read and set in the comparison unit 29a. Will be.

On the other hand, the measured data generator 27a in the abnormality judging means 26a detects the rise of the control signal detection sensor 16 from OFF to ON, that is, the start of the descending operation of the polishing head 6, and starts the processing. The timer provided in the CPU 19 is started to start measuring the elapsed time after the start of the movement. At the same time, the position detecting means 14 starts to detect the current position of the polishing head 6 and starts a sampling process at predetermined intervals.

The actual measurement data 28a required by the abnormality determining means 26a using the movement stroke 21a as reference data is the movement stroke of the polishing head 6.

Accordingly, when detecting the end of the lowering operation of the polishing head 6, the measured data generator 27a subtracts the value of the movement start position from the value of the movement end position of the polishing head 6, and determines the polishing head in this cycle. The measured data 28a of the movement stroke No. 6 is obtained, and this value is output to the comparison unit 29a.

The comparing section 29a compares the actual measurement data 28a of the movement stroke of the polishing head 6 with the movement stroke 21a which is the reference data, and determines whether or not the magnitude difference between the two is within a predetermined range. If the difference is within a predetermined range, it is determined that there is no abnormality. If the difference exceeds a predetermined range, it is determined that there is an abnormality, and an abnormality detection signal is output.

The abnormality detection signal is transmitted to the abnormality determination unit 1
8 is input to the alarm unit 25 via the input / output circuit 23 and the AD / IO board 17, and the alarm unit 25 performs processing such as blinking of a patrol light or activation of an alarm buzzer.

FIGS. 5 and 6 are flowcharts specifically showing an example of processing repeatedly executed by the CPU 19 for each sampling cycle in order to achieve the function of the abnormality determining means 26a.

The flag F shown in FIG. 5 and FIG.
Is a flag indicating the progress of the process by the abnormality determining means 26a, and its initial value is 0.

The CP that has started processing for each sampling period
U19 first determines the value of the flag F (step a)
1). At this stage, since the value of the flag F is 0, CP
Next, U19 determines whether or not the ON state of the control signal is detected by the control signal detection sensor 16, that is, whether or not the supply of air to the cylinder of the head feed mechanism 11 has been started (step a2). , The control signal is OF
If it is F, the processing of this cycle is ended as it is.

While such processing is repeatedly executed, the result of determination in step a2 becomes true and the control signal
N, when it is confirmed that the supply of air to the cylinder of the head feed mechanism 11 has been started, the CPU 19 reads a signal from the head position determination means 15 (step a).
3) It is determined whether the polishing head 6 is located on the polishing table 4 or the load cup 7 (step a4).

Then, the polishing head 6 is moved to the polishing table 4
In the upper position, that is, at the right position in FIG.
The CPU 19 reads the reference data for the polishing table position from the reference data of the movement stroke 21a stored in the non-volatile memory 21 and sets the value in the reference value storage register (step a5). The polishing head 6
Is located on the load cup 7, that is, at the left position in FIG. 1, the reference data for the load cup position is read out of the reference data of the movement stroke 21 a stored in the nonvolatile memory 21, and the value is read. Is set in the reference value storage register (step a6).

Next, the CPU 19 sets 1 to the flag F, stores that the supply of air to the cylinder of the head feed mechanism 11 has started (step a7), and controls the polishing head 6 via the position detecting means 14. currently reading position _{V n} (step a8), the position control start position S
_It is stored as ₀ , and the timer T is reset and restarted (step a9).

[0052] Then, CPU 19, the absolute value of the current difference by subtracting the value of the position _{V n} from the control start position _{S 0} of the polishing head 6 _| V n -S ₀ | look, this difference exceeds the set value α It is determined whether or not there is (step a10). The set value α is
This is a set value for determining whether or not the lowering operation of the polishing head 6 is actually started by the supply of air to the head feed mechanism 11.

If the result of the determination in step a10 is false, it means that the lowering operation of the polishing head 6 has not yet started at this stage, and the CPU 19 terminates the processing of this cycle as it is.

In the processing after the next cycle, the supply of air has already been started and the flag F has already been set to 1. Therefore, the determination result in step a1 is false.

Accordingly, the CPU 19 proceeds to the determination processing of step a14, and determines whether or not the current value of the flag F is 1.

In this case, the current value of the flag F is 1,
Since the determination result of step a14 is true, the CPU 19
Again reads the current position V _n of the polishing head 6 via the position detection unit 14 (step a15), and repeats the determination process in step a10 in the same manner as above.

If the result of the determination in step a10 is false, it means that the lowering operation of the polishing head 6 has not been started yet, and the CPU 19 terminates the processing of this cycle as it is, and In the processing of step a1, step a14, step a14
15, the processing of step a10 is repeatedly executed.

While such processing is repeatedly executed, the lowering operation of the polishing head 6 is actually started, and | V _n -S
_{0 |} When the value of reaches the set value α is detected by the judgment processing at Step a10, CPU 19 stores the current value of the timer T to move the start time required storage register T _s, resets the timer T again And restart (step a1
1) The flag F is set to 2 and the fact that the actual lowering operation of the polishing head 6 has been started is stored (step a1).
2), the current position V of the polishing head 6 read in this cycle
The value of _n is stored in the cycle delay current position storage register V _n-1 (step a13), and the processing of this cycle ends.

In the processing after the next cycle, the lowering operation of the polishing head 6 has already been started, and 2 has already been set in the flag F. Therefore, the determination results in step a1 and step a14 are false, and The determination result of a16 is true.

[0060] Therefore, CPU 19 is again reads the value of the current position _{V n} of the polishing head 6 (step a17),
The current-period delayed position V _n current position storage register V
the absolute value of the difference by subtracting the _n-1 value _| V _{n -V n-1 |} look, and determines whether the difference is below the set value beta (Step a18).

The set value β indicates that the polishing head 6 has reached the lower limit.
To determine whether or not the pressing of the wafer 9 has started
Set value. Since the sampling period τ is constant,
｜ V _n-V_n-1| Is the polishing head 6 per unit time τ
The amount of movement, that is, the elapsed time since the start of descent and the polishing head
In the relationship of FIG. 8 showing the corresponding relationship with the position of FIG.
The slope of the change curve, that is, the descending speed (V_n-V_n-1) /
It is a value proportional to τ.

Accordingly, it is determined whether or not the value of | V _n -V _n-1 | is smaller than the appropriate set value β, that is, the polishing head 6
Is determined by the reaction of the force from the wafer 9 to reduce its descending speed, and thereby the polishing head 6
It can be determined whether or not has reached the lower limit.

[0063] If the judgment result of Step a18 is No, since the polishing head 6 means that does not reach the downward limit, CPU 19 is a current position V _n of the polishing head 6 read in this period Is stored in the cycle delay current position storage register Vn _-1 (step a19), and the processing of this cycle ends.

In the processing after the next cycle, the processing of step a1, step a14, and step a16 to step a19 is repeatedly executed in the same manner as described above.

If the result of the determination in step a18 becomes true during the execution of such processing repeatedly, and it is confirmed that the polishing head 6 has reached the lowering limit, the CPU
19 stores the current value of the position V _n of the polishing head 6 to the movement end position storage register S _e stores the current value of the timer T to travel time storage register T _e (step a
20), determines the value of the movement stroke X of subtracting the value of the movement end position storage register _S control start position from the value of _{e S 0} becomes measured data 28a (step a21).

Next, the CPU 19 subtracts the value of the moving stroke 21a, which is the reference data, from the value of the moving stroke X as the actually measured data, and determines whether or not the difference exceeds a predetermined range γ. (Step a
22).

As described above, the polishing head 6 may be located on the polishing table 4 or may be located on the load cup 7, and the moving stroke of the polishing head 6 differs depending on these conditions. By the processing of steps a3 to a6, appropriate reference data corresponding to the location of the polishing head 6 is stored in the reference value storage register. Therefore, the consistency of the correspondence between the actually measured data and the reference data Is guaranteed.

If the result of the determination in step a22 is true, that is, if it is determined that there is a significant difference between the actually measured data and the reference data, the CPU 19
Determines that the lowering operation of the polishing head 6 has an abnormality, and determines whether the input / output circuit 23 and the AD
Output an alarm signal to the alarm unit 25 via the IO board 17 (step 23), and cause the alarm unit 25 to execute processing such as blinking of a patrol light or activation of an alarm buzzer.

If the determination result of step a22 is false, it means that there is no abnormality in the lowering operation of the polishing head 6, so that the process of step a23 is not executed. Therefore, in this case, the alarm unit 25 does not operate.

The release of the alarm can be performed by operating the reset switch of the alarm unit 25.

When the operation schedules of a large number of CMP machines are managed by a host computer, a cell controller, or the like, the host computer, the cell controller, or the like, sends an alarm together with the device number of the CMP machine. A signal may be output, and the occurrence of an abnormality may be displayed on a monitor such as a host computer or a cell controller. Of course, it is also possible to save the history of occurrence of abnormality as data.

Then, the CPU 19 that has completed the determination processing in step a22 or the alarm output processing in step a23.
Sets the flag F3 to 3 and stores that the determination process corresponding to one cycle of the machine operation is completed (step a).
24), the processing in this cycle ends.

Since the flag F has already been set to 3 in the processing after the next cycle, steps a1 and a1 are executed.
4, the determination result of step a16 is false, and the CPU 19
Determines whether the control signal ON state of the control signal is detected by the control signal detection sensor 16 (step a25).

As described above, at this stage, the polishing head 6 has already reached the lowering limit, and the determination as to whether there is any abnormality has been completed. However, in actuality, it is necessary to perform the polishing operation and the suction operation of the wafer 9. The supply of air to the cylinder of the head feed mechanism 11 is continued for a while, and during this time, the state of the control signal detected by the control signal detection sensor 16 is kept ON.

During this time, the result of the determination at step a25 is false, and the CPU 19 simply proceeds to step a1 and step a25.
Only the determination process of step 14, step a16, and step a25 is repeatedly executed, and the process is on standby. No substantial process is performed.

While such determination processing is repeatedly executed, the polishing operation and the suction operation in one cycle are completed, and the supply of air to the cylinder of the head feed mechanism 11 is stopped. Then, the state of the control signal detected by the control signal detection sensor 16 becomes OFF, and the CPU
19 detects this in the determination processing of step a19 and resets the flag F to the initial value 0 again (step a2).
6).

As a result, the processing of the CPU 19 completely returns to the initial state, and enters a standby state waiting for the control signal detection sensor 16 to detect the ON state of the control signal again.

Therefore, all the above-described processes are repeatedly executed each time the supply of air to the cylinder of the head feed mechanism 11 is started.

When an abnormality is detected in the movement stroke X of the polishing head 6 by the above processing, the cause may be that the polishing head 6 is not completely lowered to the lowest point or the polishing head 6 It is possible that the descent was started from a state where it did not return sufficiently.

[0080] Incidentally, it is also possible to determine the presence or absence of abnormality based on the value of the movement end position storage register S _e, when variation occurs in the value of the movement end position storage register S _e, the polishing head 6 It is considered that the cause of the abnormality is that the is not lowered to a position where it is normally lowered.

As described above, as an example, the abnormality determining means 26 using the movement stroke of the polishing head 6 as reference data.
Although the actual processing operation of the CPU 19 has been described taking the case of a as an example, even when the other reference data 21b to 21h are used, the overall processing flow is almost the same.

Hereinafter, a process for using other reference data 21b to 21h will be briefly described.

First, when the travel time 21b is used as reference data to generate actual measurement data of travel time and to compare the two, the process of steps a5 and a6 in the flowchart of FIG. Instead of the moving stroke 21a, the required moving time 21b according to the location of the polishing head 6 is set as reference data in the reference value storage register.

[0084] Since the measured data of the required moving time is automatically set to the required moving time storage register T _e by the processing in step a11 and step a20 of FIG. 5, the value and travel time of T _e in the processing of step a22 2
1b may be compared, and the presence or absence of an abnormality may be determined based on whether or not the difference exceeds a predetermined value range.

When it is determined that the required moving time _Te is abnormal, it is considered that the cause is that the vertical movement of the polishing head 6 is not smooth.

When the position change pattern 21c is used as reference data to generate measured data of the position change pattern and compare the two, the process of steps a5 and a6 in the flowchart of FIG. Instead of the movement stroke 21a, a position change pattern 21c corresponding to the location of the polishing head 6 is selected as reference data.

[0087] measured data of the position change pattern is now out reading the values of the position V _n of the polishing head 6 in the processing of step a17 in FIG. 6, the current position V _n and the timer T
, Ie, the two-dimensional array data of (T, V _n ), which is the correspondence between the elapsed time after the start of movement and the movement position, can be obtained one after another. Therefore, the magnitude of the difference between the actually measured data and the above-described reference data is determined by the processing in step a21.

The magnitude of the difference is determined, for example, by subtracting the value of the position data of the reference data corresponding to the same elapsed time from the value of the position data of the actually measured data corresponding to the same elapsed time based on the elapsed time after the start of movement. By squaring each of them and adding those values over all combinations of data.

Finally, in the determination processing of step a22,
The presence or absence of an abnormality may be determined based on whether or not this added value exceeds a predetermined value range.

When it is determined that there is an abnormality in the position change pattern, it is considered that the moving speed of the polishing head 6 fluctuates because the vertical movement of the polishing head 6 is not smooth, and a trapping occurs.

When the average moving speed 21d is used as reference data to generate measured data of the average moving speed and to compare the two, the processing of steps a5 and a6 in the flowchart of FIG. Instead of the moving stroke 21a, the average moving speed 21d corresponding to the position of the polishing head 6 is set in the reference value storage register as the reference data.

[0092] Measurement of the average moving speed data, since the measured value T _e measured value X and the travel time storage register of the moving stroke 21a has already been obtained, the arithmetic expression of X / T _e in the process of step a21 It can be obtained by executing. Therefore, X / T _{e in} the process of step a22
Is compared with the value of the average moving speed 21d, and the presence or absence of an abnormality may be determined based on whether or not the difference exceeds a predetermined value range.

If it is determined that there is an abnormality in the average moving speed, the polishing head 6 is caught during operation,
It is considered that the cause is that the polishing head 6 does not continuously move smoothly.

When the speed change pattern 21e is used as reference data to generate measured data of the speed change pattern and to compare the two, the process of steps a5 and a6 in the flowchart of FIG. Instead of the moving stroke 21a, a speed change pattern 21e corresponding to the position of the polishing head 6 is selected as reference data.

[0095] measured data of the velocity change pattern is 1 just before running V _n -V _n-1 of the arithmetic expression when reading the current position values V _n of the polishing head 6 in the processing of step a17 of FIG. 6 The moving distance of the polishing head 6 during the sampling period is obtained, and the moving distance is divided by the sampling period τ to calculate the moving speed ΔV of the polishing head 6 during the immediately preceding sampling period.
The relationship between V and the time measured by the timer T, that is, the relationship between the elapsed time after the start of the movement and the movement speed (T, ΔV).
Can be obtained by successively storing two-dimensional array data. Therefore, the magnitude of the difference between the actually measured data and the above-described reference data is determined by the processing in step a21.

The processing for determining the magnitude of the difference is performed, for example, by calculating the speed of the reference data corresponding to the same elapsed time from the value of the speed data of the actually measured data corresponding to the same elapsed time based on the elapsed time after the start of the movement. It can be determined by subtracting the data values and squaring them, and adding those values over all data combinations.

Finally, in the process of step a22, the presence or absence of an abnormality may be determined based on whether or not the added value exceeds a predetermined value range. Since the sampling period τ is constant, it is not always necessary to divide the moving distance during one sampling period by the sampling period τ to obtain the moving speed during one sampling period. The movement distance between cycles itself may be used as a value that substitutes for the movement speed during one sampling cycle. However, it is premised that the moving amount corresponding to one sampling period is stored on the side of the speed change pattern 21e instead of the substantial speed.

When it is determined that there is an abnormality in the speed change pattern, it is considered that the cause is that the vertical movement of the polishing head 6 is not smooth, and that the polishing head 6 is caught.

Also, when using the moving speed 21f as reference data to generate actual measured data of the moving speed and to compare them, step a in the flowchart of FIG.
5, instead of the moving stroke 21a as the reference data in the process of step a6, a moving speed 21f corresponding to the location of the polishing head 6 is selected as the reference data.

[0100] measured data of the moving speed, the processing of step a17 in FIG. 6, 1 just before running the current position V _n arithmetic expression of V _n -V _n-1 when reading the value of the polishing head 6 The moving distance of the polishing head 6 during the sampling period is obtained, and the moving distance is divided by the sampling period τ to calculate the moving speed ΔV of the polishing head 6 during the immediately preceding sampling period. The relationship between T and the measurement time, that is, the two-dimensional array data of (T, ΔV), which is the relationship between the elapsed time after the start of movement and the movement speed, can be obtained one after another.

In the processing for obtaining the magnitude of the difference, for example, the moving speed 21f as the reference data is subtracted from each value of the speed data of the actually measured data to obtain the absolute value of the deviation for each speed data at each time point. The largest value of
This is performed by determining the value of the deviation of the moving speed data that deviates most from the reference moving speed as the final difference amount.

Finally, in the process of step a22, the presence or absence of an abnormality may be determined based on whether or not the difference exceeds a predetermined value range.

When it is determined that the moving speed of the polishing head 6 is abnormal, whether instantaneous or not, it indicates that the continuous movement of the polishing head 6 is hindered in some way.

Also, when using the required moving start time 21g as the reference data and generating the actual measurement data of the required moving start time and comparing the two, the processing at steps a5 and a6 in the flowchart of FIG. Instead of the movement stroke 21a as data, the required movement start time 21g is set in the reference value storage register as reference data.

[0105] Since the measured data of the movement start time required is automatically set to the movement start required time storage register T _s through the process of step a9 and step a11 in FIG. 5, the measured movement start time required in the process of step a22 the comparator compares the value of the movement start time required 21g is a value with the reference data of the data T _s, if to determine the presence or absence of abnormality depending on whether the difference exceeds the range of a preset predetermined value Good.

If it is determined that there is an abnormality in the required movement start time, it is considered that the catch has occurred at the operation start position of the polishing head 6 and the start of the descending operation is delayed.

Further, when the relationship 21h between the elapsed time after the start of the movement and the movement position is used as reference data, actual measurement data of the relationship between the elapsed time after the start of the movement and the movement position is generated, and the two are compared. In the processing of steps a5 and a6 in the flowchart of FIG. 5, instead of the movement stroke 21a as reference data, a relationship 21h between the elapsed time after the start of movement and the movement position is selected as reference data.

Measurement data of the relationship between the elapsed time after the start of movement and the movement position, that is, (T,
V _n ) can be obtained in the same manner as in the case of the measured data of the position change pattern described above.

Then, the difference is obtained by subtracting the value of the position data of the reference data corresponding to the same elapsed time from the value of the position data of the actually measured data corresponding to the same elapsed time based on the elapsed time after the start of the movement. Is performed for all combinations of data having the same elapsed time. Finally, if there is at least one combination of the reference data and the actually measured data whose difference exceeds a predetermined value range, it is determined that there is an abnormality.

The difference from the above-described process of determining an abnormality using the position change pattern as reference data is that instead of evaluating the overall shift of the entire position change pattern, each of the movement positions at each elapsed time is individually determined. The point is that the presence or absence of an abnormality is determined by comparison.

If it is determined that there is an abnormality in the relationship between the elapsed time after the start of the movement and the movement position, it means that the polishing head 6 is operating within the normal operation allowable range within the specified time. It is considered that there is a possibility that some abnormality has occurred in the vertical movement mechanism of the polishing head 6.

In the above embodiment, the movement of the polishing head 6 is abnormal, the movement required time is abnormal, the position change pattern is abnormal, the average movement speed is abnormal, the speed change pattern is abnormal, the movement speed is abnormal, and the movement start is required. Either time abnormality or abnormality in the relationship between the elapsed time after the start of movement and the movement position
The case where the presence or absence of an abnormality in the descending operation of the polishing head 6 is determined by selectively using one of the two as a criterion has been described. It is also possible to configure. An example is shown in FIG.

In FIG. 7, reference numerals 26a to 26h denote abnormality determination means for each item described above, each of which is constituted by processing on software executed by the CPU 19 and the ROM 20 of the abnormality determination unit 18. . However, in the embodiment of FIG. 7, the alarm unit 25 is not actuated immediately even when an abnormality detection signal is output from the abnormality judging means 26 a to 26 h. This is finally determined by the operation abnormality comprehensive determination determining means 31.

Similarly to the above, reference numeral 14 denotes a position detecting means for detecting the vertical movement position of the polishing head 6;
Is head position determining means for determining whether the polishing head 6 is located on the polishing table 4 or the load cup 7, and these elements are abnormality determining means 26a
~ 26h can be used in common.

The timer T is set to the above-described abnormality determination means 2
6a is intended processing similar to the use by timer in the are used to determine the travel time T _e and the movement start duration T _s.

Reference numeral 26a denotes an abnormality determining means for detecting an abnormality in the movement stroke of the polishing head 6, as described above with reference to the flowcharts of FIGS.

Reference numerals 26b to 26h denote abnormality determining means for detecting an abnormality in the required moving time, abnormality determining means for detecting an abnormality in the position change pattern, and detecting an abnormality in the average moving speed, respectively. Abnormality determining means for detecting an abnormality in the speed change pattern, abnormality determining means for detecting an abnormality in the moving speed,
Abnormality determination means for detecting an abnormality in the time required to start the movement, and abnormality determination means for detecting an abnormality in the relationship between the elapsed time after the start of the movement and the movement position. The principle has already been described to the extent practicable.

The operation abnormality comprehensive judgment judging means 31 is for counting the number of judgment results indicating that there is an abnormality among the judgment results by the abnormality judging means 26a to 26h. It is constituted by a predetermined register (counter).

Then, the CPU 19 as the operation abnormality comprehensive judgment judging means 31 counts the number of judgment results of abnormality among the judgment results of the abnormality judging means 26a to 26h, and sums the number of judgment results of abnormality to a predetermined value. Only when the value exceeds N, a final abnormality detection signal is output and the alarm unit 25 is output.
Is activated to warn the operator or administrator of the occurrence or possibility of the lowering abnormality of the polishing head 6.

That is, the value of the predetermined value used as a criterion in the abnormality determining means 26a to 26h, for example, the value of the predetermined value γ shown in the flowcharts of FIGS. 5 and 6, can be set arbitrarily. If the criteria for determining the presence or absence of abnormalities are set strictly, it is also possible to detect slight abnormalities that do not hinder the actual polishing process. The nature can be indicated by an alarm to an operator or a manager.

It is also possible to arbitrarily set the value of the predetermined value N used for the final judgment by the operation abnormality comprehensive judgment judging means 31, and to determine the final abnormality judgment based on the value of N. Severity can be adjusted. Naturally, assuming that the output of the abnormality determination means 26a to 26h when the abnormality is abnormal is 1 and the output when there is no abnormality is 0, the logical AND or the logical sum thereof is obtained to make the final abnormality determination. It is also possible to

Further, a software switch or the like for selectively executing the processing constituting the abnormality determination means 26a to 26h is provided so that the type and number of abnormality determination means used for actual determination can be arbitrarily combined. It is also possible.

When the operation schedule of a large number of CMP machines is managed by a host computer, a cell controller, or the like, or when the abnormality determination unit 18
If a monitor or the like is mounted on itself, it may be configured to display a statement suggesting the cause of the abnormality in accordance with the determination result by each of the abnormality determining means 26a to 26h. For example, when an abnormality is detected by the abnormality determination unit 26a, "stroke end abnormality" is detected. When an abnormality is detected by the abnormality determination unit 26g, "the operation start point is caught". Determination means 26b, 26c, 26d, 26e, 26f, 26
If an abnormality is detected in h, a statement such as "There is an obstacle in the middle of the stroke" would be appropriate.

In the above embodiment, when the polishing head 6 is lowered, it is determined whether or not the feed operation is abnormal.
If the configuration is such that the change to the FF is detected and the processing substantially equivalent to the above is performed, in addition to the abnormality detection during the descending operation, it is also possible to detect an abnormality during the raising operation of the polishing head 6. .

In the case of a CMP processing machine provided with a plurality of polishing tables and performing polishing by moving the polishing head 6 between the plurality of polishing tables by the cooperative operation of the horizontal feed mechanism and the head feed mechanism 11, The first description is made by providing a load cup 7 and normal value storage means for storing reference data for each polishing table and selecting the reference data corresponding to the polishing table where the polishing head 6 is located. As in the case of the polishing table 4 and the load cup 7 in the embodiment, the abnormality of the vertical movement of the polishing head 6 is always determined based on the optimal reference data regardless of which polishing table the polishing head 6 is located on. Will be able to

As the head feed mechanism 11, a linear feed mechanism including a ball screw & socket, a servomotor, and the like can be used in addition to the cylinder.

When a servomotor or the like is used, the drive torque acting on the head feed mechanism 11, that is, the reaction force of the resistance acting on the polishing head 6 can be obtained by detecting the drive current. In addition to the above-described reference data and actual measurement data based on the time, position, and speed, it is also possible to use the determination of abnormality, such as the occurrence of a snag between the polishing head 6 and the guide 10 and a change in frictional resistance.

[0128]

According to the CMP machine of the present invention, since the vertical movement of the polishing head of the CMP machine is constantly monitored by the position detecting means, various actually measured data which can be specified from the relationship between the position and the time. For example, various data such as a movement stroke of the polishing head, a required movement time, a position change pattern, an average movement speed, a speed change pattern, a movement speed, a required movement start time, and a relationship between an elapsed time after the start of movement and a movement position. Based on the above, it is possible to reliably detect the occurrence of the abnormality of the vertical movement of the polishing head and its precursor without the need for the operator to directly confirm the operation. For this reason, the response from the occurrence of the abnormality is quickened, and the stop time of the apparatus can be shortened.

In addition, since a state in which an abnormality starts to appear a little can be detected, the problem of continuously producing defective products can be solved, and wasteful work such as product sorting can be eliminated.

Further, since it is possible to predict the failure of the apparatus, the time required for repair and replacement of the apparatus can be reduced if measures such as purchasing necessary materials in advance are taken.

Further, it is possible to perform a part replacement and a repair work by intentionally stopping the apparatus, and to perform a part replacement and a repair work at a time when the apparatus is not used. In such a case, the number of parts replacement and repair work that is stopped halfway can be reduced, and the running cost of the apparatus can be improved.

Further, since a failure can be predicted in advance, it is not necessary to stop the apparatus during processing of a product wafer, and it is possible to reduce the number of steps of measuring the thickness of a product again and polishing again during processing. Efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a main part of a CMP processing machine according to an embodiment of the present invention.

FIG. 2 is a functional block diagram illustrating a main part of an abnormality determination unit provided in the CMP processing machine of the embodiment.

FIG. 3 is a conceptual diagram illustrating an example of a storage state of reference data in a nonvolatile memory.

FIG. 4 is a functional block diagram schematically illustrating an example of a process performed by an abnormality determination unit of the abnormality determination unit.

FIG. 5 is a flowchart more specifically illustrating an example of processing of a CPU functioning as an abnormality determination unit.

FIG. 6 is a continuation of the flowchart more specifically illustrating an example of processing of the CPU functioning as an abnormality determination unit;

FIG. 7 is a functional block diagram illustrating an outline of a process when performing an abnormality determination using a plurality of determination criteria.

FIG. 8 is an operation principle diagram showing an example of the relationship between the elapsed time after the start of lowering of the polishing head and the lowering position of the polishing head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CMP processing machine 2 Processing machine main body 3 Base part 4 Polishing table 5 Polishing pad 6 Polishing head 6a Head main body 6b Chuck part 7 Load cup 8 Polishing liquid 9 Wafer 10 Guide 11 Head feed mechanism 12 CMP control device 13 Pressure control unit 14 Position Detecting means 15 Head position determining means 16 Control signal detecting sensor 17 AD / IO board 18 Abnormality determining unit 19 CPU 20 ROM 21 Nonvolatile memory 21a to 21h Reference data 22 RAM 23 Input / output circuit 24 Buffer 25 Alarm unit 26 Abnormality determining means 26a 26h Abnormality determination means for each item 27a Actual measurement data generation section 28a Actual measurement data 29a Comparison section 30a Reference data selection section 31 Operation abnormality comprehensive determination determination means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shigeo Yoshida 5-7-1 Shiba, Minato-ku, Tokyo Within NEC Corporation (72) Inventor Kazuichi Kazu 5-7-1 Shiba, Minato-ku, Tokyo Japan F-term in the Electric Company (reference) 3C034 AA13 AA17 CA11 CA15 CA27 CB13 DD18 3C058 AA07 BA04 BA07 BA09 BB02 BB08 BC03 CB03 DA12 DA17

Claims (11)

[Claims] A polishing table equipped with a polishing pad;
A polishing head that holds and rotates a wafer, and a head that moves the polishing head toward and away from the polishing table in a direction normal to the polishing table while a rotating surface of the polishing head is perpendicular to the direction normal to the polishing table. CMP with feed mechanism
A processing machine, a position detecting means for detecting a moving position of the polishing head,
Normal value storage means for storing reference data corresponding to normal operation of the head feed mechanism, which can be specified from the relationship between the position of the polishing head and the elapsed time after the start of movement, and detecting the position when the head feed mechanism operates. Means for obtaining actual measurement data of the same type as the reference data based on the position data detected in chronological order; comparing the actual measurement data with the reference data stored in the normal value storage means; A CMP processing machine comprising: abnormality determination means for outputting an abnormality detection signal when the value exceeds the threshold. 2. The normal value storage means stores a movement stroke of the polishing head corresponding to a normal operation of the head feed mechanism as reference data, and the abnormality determination means calculates the movement stroke of the polishing head by actual measurement data. 2. The CMP processing machine according to claim 1, which is determined as: 3. The normal value storage means stores a time required for moving the polishing head corresponding to a normal operation of the head feed mechanism as reference data, and the abnormality determination means includes:
2. The CMP machine according to claim 1, wherein a required time for moving the polishing head is obtained as measured data. 4. A polishing head position change pattern corresponding to a normal operation of the head feed mechanism is stored as reference data in the normal value storage means, and the abnormality determining means stores the polishing head position change pattern in the polishing head. 2. The CMP machine according to claim 1, wherein the CMP machine is obtained as measured data. 5. The normal value storage means stores an average moving speed of the polishing head corresponding to a normal operation of the head feed mechanism as reference data, and the abnormality determination means includes:
2. The CMP machine according to claim 1, wherein the average moving speed of the polishing head is obtained as measured data. 6. The normal value storage means stores a speed change pattern of the polishing head corresponding to a normal operation of the head feed mechanism as reference data, and the abnormality determining means stores the speed change pattern of the polishing head. 2. The CMP machine according to claim 1, wherein the CMP machine is obtained as measured data. 7. The normal value storage means stores a moving speed of the polishing head corresponding to a normal operation of the head feed mechanism as reference data, and the abnormality judging means stores a moving speed of the polishing head at each position. 2. The CMP processing machine according to claim 1, wherein is obtained as actual measurement data. 8. The normal value storage means stores, as reference data, a time required to start movement of the polishing head corresponding to a normal operation of the head feed mechanism, and the abnormality determination means stores a time required to start movement of the polishing head. The CMP machine according to claim 1, wherein the time is obtained as measured data. 9. The normal value storage unit stores, as reference data, a relationship between an elapsed time after the start of movement of the polishing head and a movement position corresponding to a normal operation of the head feed mechanism, and the abnormality determination unit includes: 2. The CMP machine according to claim 1, wherein a relationship between an elapsed time after the start of movement of the polishing head and a movement position is obtained as measured data. 10. A polishing table on which a polishing pad is mounted, a polishing head for holding and rotating a wafer, and a polishing head with a rotating surface of the polishing head orthogonal to a normal direction of the polishing table. A head feed mechanism for moving the polishing table toward and away from the polishing table in a normal direction.
MP processing machine, a position detecting means for detecting the moving position of the polishing head,
The moving stroke, the required moving time, the position change pattern, the average moving speed, the speed changing pattern, the moving speed, the required moving start time, and the elapsed time after starting the moving of the polishing head corresponding to the normal operation of the head feed mechanism. Normal value storage means for storing reference data relating to the movement position,
The moving stroke, required moving time, position change pattern, average moving speed, speed changing pattern, moving speed, moving speed of the polishing head based on the position data detected in time series by the position detecting means when the head feed mechanism operates. The required start time, and the measured data of the relationship between the elapsed time after the start of the movement and the movement position, determine the measured data of each item and the corresponding reference data stored in the normal value storage means, An abnormality determination unit for each item that outputs an abnormality detection signal when the difference exceeds a predetermined value; and a final abnormality detection signal when the number of abnormal detection signals output from each abnormality determination unit exceeds a set value. A CMP processing machine comprising: an operation abnormality total determination unit that outputs a signal. 11. A polishing machine for disposing a load cup for mounting a wafer to be polished in parallel with the polishing table, and reciprocating the polishing head between the load cup and the polishing table. A horizontal feed mechanism, and a head position determining unit for determining whether the polishing head is located on the load cup side or the polishing table side, and the normal value storage unit includes the polishing head. Reference data for a load cup position to be used when located on the load cup and reference data for a polishing table position to be used when the polishing head is located on the polishing table are stored.
A reference data selection unit that selects one of the reference data for the load cup position and the reference data for the polishing table position from the normal value storage unit in accordance with the determination result of the head position determination unit; Any one of claim 1, claim 2, claim 3, claim 4, claim 5, claim 6, claim 7, claim 8, claim 9, or claim 10 having a function. CM described in item 1
P processing machine.