JP7330905B2 - Self-diagnostic device for contact thickness gauge - Google Patents

Description

The present invention provides a contact thickness measuring instrument for measuring the thickness of a substrate to be measured (for example, a wafer) by bringing a contactor of the contact thickness measuring instrument into contact with one surface of a substrate to be measured (for example, a wafer). The present invention relates to a self-diagnostic device for a contact-type plate thickness gauge having a function of self-diagnosing whether or not the thickness gauge is operating normally without error.

2. Description of the Related Art Conventionally, in the field of semiconductor manufacturing, a wafer grinding apparatus for grinding the surface of a semiconductor wafer such as a silicon wafer (hereinafter simply referred to as "wafer") is known (see, for example, Patent Document 1).

The grinding device described in Patent Document 1 is a grinding device to which an in-field grinding device (BG, back grinder) technology is applied. In this grinding machine, for example, as a pre-work inspection before one lot starts, a method of measuring the thickness of the wafer before processing or the thickness of the wafer after processing is adopted. is brought into contact with, for example, the upper surface of a wafer placed on a substrate mounting table. In addition, the operator who operates the measuring device visually confirms whether or not the operation of the measuring device itself is functioning correctly.

Japanese Patent No. 3510177

In the method in which the operator visually confirms whether or not the operation of the measuring instrument itself is functioning correctly, the workability is poor, and the diagnostic criteria for acceptance or rejection differ slightly from operator to operator. There was a problem of lack of accuracy. Furthermore, there is a problem that the operator's skill is required for diagnosis. In addition, if sludge or the like adheres to the contactor, or if the oil inside the measuring instrument deteriorates and it does not operate normally, it is necessary to check whether the measuring instrument itself is functioning correctly was difficult to diagnose.

Therefore, we have improved the accuracy of measurement by a measuring instrument, and have made it possible to easily and accurately diagnose the measuring instrument without requiring skill in the diagnostic criteria of the measuring instrument itself. A technical problem to be solved arises in order to provide a self-diagnostic device in a thickness gauge, and the present invention aims to solve this problem.

SUMMARY OF THE INVENTION The present invention has been proposed to achieve the above objects. A self-diagnostic device in a contact-type plate thickness measuring instrument that detects the thickness of the substrate to be measured by bringing it into contact with one surface of the substrate, wherein the detecting arm member causes the contactor to contact the one surface of the substrate to be measured. and a second detection arm member for bringing the contact into contact with the mounting surface, wherein the first detection arm member is positioned between a reference position and the object. a first measuring means for measuring the movement time and height of the contactor of the first detection arm member when moving between one surface of the measurement substrate; and the contactor of the second detection arm member. second measuring means for measuring the movement time and height of the contactor of the second detecting arm member when the contactor moves between the reference position and the mounting surface; and measuring by the first measuring means It is calculated whether or not the drift amount, which is the difference between the height of the contactor measured by the second measuring means and the height of the contactor measured by the second measuring means, is within a predetermined range. and control means for diagnosing whether any one of the detection arm member and the second arm member is abnormal.

According to this configuration, the control means controls the height of the contact on the first detection arm member measured by the first measurement means and the height of the contact on the second detection arm member measured by the second measurement means. It is calculated whether or not the drift amount, which is the difference between the height of the sensor and the sensor, is within a predetermined range, and whether or not there is an abnormality in either the first detection arm member or the second detection arm member. can be automatically diagnosed. As a result, the determination of whether the operating state of the first detection arm member is possible and the determination of whether the operating state of the second detection arm member is possible can be made easily and accurately without troubling the operator. processing can be performed quickly. In addition, when the plate thickness is measured using a pair of detection arm members, ie, the first detection arm member and the second detection arm member, two detection arm members, the first detection arm member and the second detection arm member, are used. By monitoring one detection arm member, errors due to heat and the measurement environment are eliminated, and the plate thickness measurement accuracy and the accuracy of diagnosing the operating state of each detection arm member are further improved.

According to a second aspect of the present invention, there is provided a contact thickness measuring instrument for detecting the thickness of a substrate to be measured by bringing a contact provided on a reciprocally movable detection arm member into contact with one surface of the substrate to be measured. A self-diagnostic device that measures the movement time and height of the contactor of the detection arm member when the contactor of the detection arm member moves between a reference position and one surface of the substrate to be measured. Diagnosing the operating state of the detection arm member by comparing the measuring means and the measured value of the measuring means with a pre-stored standard map showing the relationship between the movement time of the contactor and the height of the contactor. and a control means.

According to this configuration, the control means measures the movement time and the height of the contact measured by the measurement means when the contact on the detection arm member moves between the reference position and the surface of the substrate to be measured. and a pre-stored standard map showing the relationship between the moving time and the height of the contactor, thereby automatically diagnosing the operating state of the detection arm member. As a result, it is possible to easily and accurately diagnose the operating state of the detection arm member without troubling the operator, and to quickly perform necessary processing.

In the invention according to claim 3, a mounting surface for mounting a substrate to be measured and a contactor provided on a reciprocally movable detection arm member are provided on one surface of the substrate to be measured mounted on the mounting surface. A self-diagnostic device for a contact-type board thickness measuring instrument that detects the thickness of the substrate to be measured by bringing the substrates into contact with each other, wherein the contactor of the detection arm member moves between the reference position and the mounting surface. Measuring means for measuring the movement time and height of the contact of the detection arm member when moving, and the relation between the movement time and the height of the contact, in which the measurement values of the measuring means are stored in advance. and control means for diagnosing the operating condition of the sensing arm member by comparing with a standard map showing the .

According to this configuration, the control means controls the movement time and height of the contact measured by the measuring means when the contact on the detection arm member moves between the reference position and the mounting surface, and It is possible to automatically diagnose the operating state of the detection arm member by comparing it with a pre-stored standard map showing the relationship between the moving time and the height of the contactor. As a result, it is possible to easily and accurately diagnose the operating state of the detection arm member without troubling the operator, and to quickly perform necessary processing.

According to a fourth aspect of the present invention, in the configuration according to any one of the first to third aspects, when the control means diagnoses that the operating state of the detection arm member in the contact-type plate thickness measuring instrument is abnormal, , a self-diagnostic device for a contact-type plate thickness gauge having alarm means for announcing alarm information;

According to this configuration, when the control means diagnoses that the state of the contact-type plate thickness measuring instrument is abnormal, the alarm means can be activated and notified by the alarm information, so that the abnormality can be detected quickly.

According to the invention, the time and height required for the contactor of the detection arm member to move between the reference position and the surface of the substrate to be measured from the reference position to the surface of the substrate to be measured, or When the contactor of the detection arm member moves between the reference position and the mounting surface, the time and height required for the contactor to move from the reference position to the mounting surface are measured by the measuring means, and are measured by the measuring means. It is possible to automatically diagnose whether or not the plate thickness measurement movement by the detection arm member is normally performed from the time and height determined, so it is easy and accurate without bothering the operator. to quickly perform the required processing.

FIG. 4 is a diagram schematically showing an example of a self-diagnostic device in the contact-type plate thickness measuring instrument according to the embodiment of the present invention; FIG. 2 is a side view of the same contact-type plate thickness measuring instrument; It is a graph for demonstrating one operation example of a self-diagnosis apparatus same as the above.

The present invention improves the accuracy of measurement by a measuring instrument, and provides a diagnostic criteria for the measuring instrument itself, which does not require skill, and enables easy and accurate diagnosis of the measuring instrument. In order to achieve the purpose of providing a self-diagnostic device in a plate thickness measuring instrument, the contactor of the reciprocally movable detection arm member is brought into contact with one surface of the substrate to be measured placed on the placement surface. In the self-diagnostic device for a contact-type plate thickness measuring instrument for detecting the thickness of the substrate to be measured, the detecting arm member brings the contactor into contact with one surface of the substrate to be measured. a detection arm member; and a second detection arm member for bringing the contactor into contact with the mounting surface, wherein the first detection arm member is positioned between a reference position and one surface of the substrate to be measured. a first measuring means for measuring the movement time and height of the contactor of the first detection arm member when moving between the contactors, and the contactor of the second detection arm member being at a reference position; second measuring means for measuring the movement time and height of the contactor of the second detection arm member when moving between the placement surface and the contactor measured by the first measuring means; It is calculated whether or not the amount of drift, which is the difference between the height of the contactor measured by the second measuring means and the height of the contactor, is within a predetermined range. This is achieved by providing a control means for diagnosing whether any one of the second arm members is abnormal.

An example according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In the examples, when referring to the number, numerical value, amount, range, etc. of constituent elements, unless otherwise specified or in principle clearly limited to a specific number, it is limited to the specific number. It does not matter if the number is greater than or less than a specific number.

In addition, when referring to the shape and positional relationship of components, etc., unless otherwise specified or in principle clearly considered otherwise, etc. include.

In addition, the drawings may exaggerate characteristic parts by enlarging them in order to make the characteristics easier to understand.

Also, in the following description, expressions indicating directions such as up, down, left and right are not absolute, and are appropriate when each part of the contact-type plate thickness measuring instrument of the present embodiment is depicted. However, if the posture changes, it should be interpreted according to the change in posture. Also, the same reference numerals are given to the same elements throughout the description of the embodiments.

1 and 2 schematically show a self-diagnostic device 11 in a contact-type plate thickness measuring instrument 10 according to the present invention. FIG. 1 is a plan view of the self-diagnostic device 11, and FIG. 2 is a side view of measuring device 10. FIG.

1 and 2, the self-diagnostic device 11 of the present embodiment performs chemical mechanical polishing (hereinafter referred to as "CMP") for flattening the surface of a wafer W, which is a substrate to be measured, for example, in a semiconductor manufacturing apparatus. ). The self-diagnostic device 11 detects the thickness of the wafer W, which is the substrate to be measured, placed on the chuck table 102 of the substrate placing table 101, and the measurement operation of the contact-type plate thickness measuring device 10 is normally maintained. An example is a case in which it is automatically determined whether or not it has been performed. However, the self-diagnostic device 11 of this embodiment can be applied not only to the wafer W but also to general substrates.

Further, the contact-type plate thickness measuring instrument 10 has a pair of contact-type plate thickness measuring instruments 10A and 10B, and the self-diagnostic device 11 diagnoses the operating states of the pair of contact-type plate thickness measuring instruments 10A and 10B. It has a configuration that allows

The contact-type plate thickness measuring instrument 10A and the contact-type plate thickness measuring instrument 10B are provided on the device base 12, and are provided on one end side of the measuring instrument main body 13 and the measuring instrument main body 13, which are fixed to each other in a plane. and a detection arm member 15 mounted so as to be reciprocally movable in the vertical direction with the link coupling portion 14 as a fulcrum.

The outer peripheral portion of the link coupling portion 14 that couples the detection arm member 15 and the measuring instrument main body portion 13 is covered with a boot 19 that serves as a bag-shaped cover made of rubber, soft plastic, or the like. .

Further, a contactor 16 is attached to the tip side of the detection arm member 15 so as to pass therethrough in the vertical direction.

Then, as shown in FIG. 1, the contact-type plate thickness measuring instrument 10A is positioned so that the contactor 16 of the detection arm member (second detection arm member) 15 can come into contact with the upper surface (base) of the chuck table 102. The contact-type plate thickness measuring instrument 10B is arranged such that the contactor 16 of the detection arm member 15 (first detection arm member) is placed on the mounting surface of the chuck table 102, and the upper surface (one surface) of the wafer W is placed. It is arranged at a contactable position.

Further, as shown in FIG. 2, the initial position of the detection arm member 15 in the contact-type plate thickness measuring instrument 10A is a reference position U where the contactor 16 is separated from the upper surface of the chuck table 102. The initial position of the detection arm member 15 in 10B is set to the same reference position U as the reference position U of the detection arm member 15 in the contact-type plate thickness measuring device 10A, where the contactor 16 is separated from the upper surface of the wafer W. FIG. This reference position U can be changed. When the contact thickness measuring instrument 10A and the contact thickness measuring instrument 10B are operated as will be described later, the contact thickness measuring instrument 10A or the contact thickness measuring instrument 10A or the contact thickness measuring instrument 10A or the contact thickness measuring instrument 10B is detected through the link coupling portion 14, respectively. The contactors 16 of the detection arm member 15 connected to the device 10B are each rotated downward, and the upper surface (base) of the chuck table 102 or the upper surface (one surface) of the wafer W to which the respective contactors 16 correspond. is configured to abut on the

The measuring instrument body 13 of the contact-type plate thickness measuring instrument 10A and the measuring instrument body 13 of the contact-type plate thickness measuring instrument 10B are each driven by air control to rotate the detection arm member 15 in the vertical direction. It is designed to let you That is, the measuring instrument main body 13 of the contact-type plate thickness measuring instrument 10A and the measuring instrument main body 13 of the contact-type plate thickness measuring instrument 10B have an air cylinder (not shown) connected to an intake pipe 17 and an exhaust pipe 18 therein. are provided. Then, when air is blown into the air cylinder through the intake pipe 17, the detection arm member 15 waiting at the reference position U is rotated downward with the link coupling portion 14 as a fulcrum, and each contactor 16 is moved accordingly. It can be brought into contact with the upper surface of the chuck table 102 or the upper surface of the wafer W. Further, after that, when the air in the air cylinder is released through the exhaust pipe 18, the detection arm member 15 is rotated upward about the link coupling portion 14, and is returned to the reference position U to wait. It has become.

Further, measuring device body 13 of contact-type plate thickness measuring device 10A has measuring means (second measuring means) for measuring time t1 from reference position U until detection arm member 15 comes into contact with the upper surface of chuck table 102. Means) 20 is provided, and time t2 from the reference position U until the detection arm member 15 comes into contact with the upper surface of the wafer W and the contactor 16 A measuring means (first measuring means) 20 for measuring the height of the is provided. In the contact-type plate thickness measuring instrument 10A and the contact-type plate thickness measuring instrument 10B, each detection arm member 15 is simultaneously rotated downward from the reference position U to lower the contactor 16. The measuring means 20 measures the times t1 and t2 until contact with the corresponding surface, and sends the time information and position information measured by the measuring means 20 to the control means 21 in real time. Also, the control means 21 is configured to measure the thickness of the wafer W based on the time information and the position information from the measuring means 20 .

In addition to measuring the thickness of the wafer W, the control means 21 controls and executes the overall operation and diagnosis of the contact-type plate thickness measuring instrument 10 and the self-diagnostic device 11, and is composed of, for example, a microcomputer. It controls the contact-type plate thickness measuring instrument 10 and the self-diagnostic device 11 according to a predetermined procedure while performing necessary arithmetic processing according to a program incorporated in the microcomputer.

By the way, as in this embodiment, the contact-type plate thickness measuring instrument 10A is connected to the measuring instrument main body 13 by the link coupling portion 14, and the outer peripheral portion of the link coupling portion 14 is covered with the boot 19; Similarly, in the contact-type plate thickness measuring instrument 10B, which is connected to the measuring instrument main body 13 by the link coupling portion 14 and the outer peripheral portion of the link coupling portion 14 is covered with the boot 19, the link coupling portion 14 and If the boot 19 is mechanically fatigued due to wear and deterioration, the time from the reference position U to contact with the upper surface of the chuck table 102 or the time from the reference position U to the contact with the upper surface of the wafer W will be reduced. , an error occurs. Therefore, in this embodiment, from the time information and position information measured by the measuring means 20, the control means 21 diagnoses the operating states of the contact thickness measuring instruments 10A and 10B, respectively. It is possible to automatically determine whether the operating states of the contact-type plate thickness measuring device 10A and the contact-type plate thickness measuring device 10B are good or bad.

Next, based on the time information and position information measured by the measuring means 20, the control means 21 diagnoses the operating states of the contact thickness measuring instruments 10A and 10B, and determines whether the control means 21 is good or bad. An example of automatic determination will be described with reference to the graph shown in FIG.

FIG. 3 shows measured values indicating the distance that the vertical axis moves between the reference position U and the upper surface (mounting surface) of the chuck table 102 or the distance that moves between the reference position U and the upper surface of the wafer W. (μm), and the horizontal axis indicates the measurement time (sec) required for the contactor 16 to come into contact with the upper surface (base) of the chuck table 102 or the upper surface (one surface) of the wafer W from the reference position U. . In the figure, curve (a) is an example of value data for each measurement time that is considered to be drawn when the contact-type plate thickness measuring device 10 is in a normal state again, and curve (b) is an example of contact-type plate thickness It is an example of value data for each measurement time drawn when the measuring device 10 is in an abnormal state. The curve (a) may be stored in advance as a measurement value of the measuring means 20 and used as a standard map standard time map showing the relationship between the movement time of the contactor 16 and the height of the contactor 16. .

When the measurement operations of the contact thickness gauge 10A and the contact thickness gauge 10B are normal, the measured value of the contact thickness gauge 10A or the measured value of the contact thickness gauge 10B is the curve (a ) shows a change that roughly follows. That is, when measurement is started, the contactor 16 on the detection arm member 15 of the contact-type plate thickness measuring instrument 10A or the contact-type plate thickness measuring instrument 10B moves between the reference position U and the mounting surface of the chuck table 102. or the movement time between the reference position U and the surface of the wafer W is about 2 to 3 seconds. However, when the movement of the detection arm member 15 is abnormal, the contactor 16 of the detection arm member 15 in the contact-type plate thickness measuring instrument 10A moves from the reference position U to the upper surface (mounting surface) of the chuck table 102. The time and height, or the time and height for the contactor 16 of the detection arm member 15 in the contact-type plate thickness measuring instrument 10B to move from the reference position U to the upper surface of the wafer W, may be other than the curve (a), such as the curve ( It reaches by drawing a curve like b).

Here, when drawing a curve other than curve (a), such as curve (b), and reaching the upper surface of chuck table 102 or the upper surface of wafer W from reference position U, contact-type plate thickness measuring instrument 10A Alternatively, the moving operation of the detection arm member 15 of the contact-type plate thickness measuring instrument 10B takes too much time as compared with the standard measurement time depicted by the curve (a). Therefore, the control means 21 determines that it is abnormal because it takes too much time for the standard time measurement. The cause of this abnormality is deterioration of the link coupling portion 14, the boot 19, or the like, sludge or the like adhering to the contactor 16, or deterioration of the oil inside the main body 13 of the measuring instrument. In addition, the cause may be that it is not operating normally. Also, at this time, the control means 21 issues an alarm from the notification means 22 connected to the control means 21 . As a result, it is notified to the outside that the operating state of the detection arm member in the contact-type plate thickness measuring device 10A or the contact-type plate thickness measuring device 10B has been diagnosed as abnormal. As a result, the operator or the like can be promptly urged to perform necessary maintenance.

Therefore, in the self-diagnostic device 11 of this embodiment, when the contactor 16 of the detection arm member 15 moves together with the detection arm member 15 between the reference position U and one surface of the wafer W, or when the contactor 16 moves from the reference position U to the chuck. When moving between the mounting surface of the table 102, the movement time and height of the contact 16 of the detection arm member 15 are measured by the measuring means 20, and the measured value measured by the measuring means 20 and the previously measured The control means 21 calculates and compares the measured values, for example, the curve (a) in FIG. The operating state of the detection arm member 15 in the plate thickness measuring instrument 10 can be automatically diagnosed. As a result, it is possible to easily and accurately diagnose the operating state of the detection arm member without troubling the operator, and to quickly perform necessary processing.

The present invention is not limited to the configuration for diagnosing the operating states of the contact-type plate thickness measuring instrument 10A and the contact-type plate thickness measuring instrument 10B as in the above embodiment, but the time information and the Based on the position information, the control means 21 determines whether the contact thickness measuring device 10A or the contact thickness measuring device 10B is operated based on the relative operating states of the contact thickness measuring device 10A or the contact thickness measuring device 10B. It may be configured to determine whether the operating state is good or bad.

That is, in the case of the detection arm members 15 operating normally, the pair of detection arm members 15 rises and lowers uniformly, so the amount of drift, which is the difference in height of each contactor 16 at the same time, remains almost zero. do. Therefore, whether the drift amount of each contactor 16 measured by the pair of measuring means 20 respectively connected to the pair of detection arm members 15 is within a predetermined range (for example, about 3 μm). It is also possible to calculate whether or not there is an abnormality by the control means 21, and to automatically diagnose whether any one of the pair of detection arm members 15 is abnormal based on the result.

In addition, instead of the structure using a pair of detection arm members 15, a plate thickness measurement configuration using one detection arm member 15 may be used. By monitoring two detection arm members, errors due to heat and measurement environment are eliminated, and more accurate diagnosis can be performed.

Also, the present invention can be modified in various ways without departing from the spirit of the present invention, and the present invention naturally extends to such modifications.

Reference numerals 10, 10A, 10B: contact-type plate thickness measuring device 11: self-diagnostic device 12: device base 13: measuring device main body 14: link connecting portion 15: detection arm member 16: contactor 17: intake pipe 18: exhaust pipe 19 : Boot 20 : Measuring means 21 : Control means 22 : Notification means 101 : Substrate mounting table 102 : Chuck table U : Reference position W : Wafer (substrate to be measured)

Claims (4)

A self contact type plate thickness measuring instrument that detects the thickness of a substrate to be measured placed on a mounting surface by bringing a contactor of a detection arm member that can reciprocate into contact with one surface of the substrate to be measured. A diagnostic device,
The detection arm member includes a first detection arm member that brings the contactor into contact with one surface of the substrate to be measured, and a second detection arm member that brings the contactor into contact with the mounting surface. , and
a first measurement for measuring the movement time and height of the contactor of the first detection arm member when the first detection arm member moves between a reference position and one surface of the substrate to be measured; means and
a second measurement for measuring the movement time and height of the contactor of the second detection arm member when the contactor of the second detection arm member moves between a reference position and the mounting surface; means and
Whether the amount of drift, which is the difference between the height of the contactor measured by the first measuring means and the height of the contactor measured by the second measuring means, is within a preset range. and a control means for diagnosing whether any one of the first detection arm member and the second arm member has an abnormality;
A self-diagnostic device in a contact-type plate thickness measuring instrument, comprising: A self-diagnostic device for a contact-type plate thickness measuring instrument that detects the thickness of a substrate to be measured by bringing a contact provided on a reciprocally movable detection arm member into contact with one surface of the substrate to be measured,
measuring means for measuring the movement time and height of the contactor of the detection arm member when the contactor of the detection arm member moves between a reference position and one surface of the substrate to be measured;
control means for diagnosing the operating state of the detection arm member by comparing the measured value of the measuring means with a pre-stored standard map showing the relationship between the moving time of the contactor and the height of the contactor;
A self-diagnostic device in a contact-type plate thickness measuring instrument, comprising: A mounting surface on which the substrate to be measured is mounted and one surface of the substrate to be measured mounted on the mounting surface are brought into contact with contactors provided on a detection arm member capable of reciprocating motion, respectively. A self-diagnostic device in a contact-type board thickness measuring instrument that detects the thickness of a board,
measuring means for measuring the movement time and height of the contactor of the detection arm member when the contactor of the detection arm member moves between a reference position and the mounting surface;
control means for diagnosing the operating state of the detection arm member by comparing the measured value of the measuring means with a pre-stored standard map showing the relationship between the moving time of the contactor and the height of the contactor;
A self-diagnostic device in a contact-type plate thickness measuring instrument, comprising: 4. The apparatus according to any one of claims 1 to 3, further comprising alarm means for notifying alarm information when said control means diagnoses that the operating state of said detecting arm member in said contact-type plate thickness measuring instrument is abnormal. A self-diagnostic device for the contact-type plate thickness measuring instrument according to the above item.

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