JP2008124402A - Self-diagnosable method of semiconductor manufacturing equipment and semiconductor manufacturing equipment as well as self-diagnosable method of polishing apparatus and polishing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a self-diagnosable method of a semiconductor manufacturing equipment which can elevate the throughput of a wafer and its semiconductor manufacturing equipment as well as a self-diagnosable method of a polishing apparatus and its polishing apparatus. <P>SOLUTION: The self-diagnosable method of the polishing apparatus includes a step to judge whether the apparatus is in a wafer-wait-state waiting for a wafer to be polished to be supplied from outside (step S102), a step to judge whether the predetermined time passed after when the apparatus has been judged to be in the wafer-wait-state (step S103), and a step to do a self-diagnosable treatment to find out the abnormality of the apparatus when the predetermined time is judged to be over (step S106). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a self-diagnosis method for a semiconductor manufacturing apparatus represented by a polishing apparatus or the like.

As a semiconductor manufacturing apparatus that performs predetermined processing on a wafer, for example, a polishing apparatus (referred to as a CMP apparatus) that precisely polishes a metal film on an interlayer insulating film in a wafer by a chemical mechanical polishing method (CMP method). It is known (see, for example, Patent Document 1). In such a polishing apparatus, a self-diagnosis process is performed to detect an abnormality of the apparatus.
JP 2002-93759 A

  However, since the conventional self-diagnosis of the polishing apparatus is always performed immediately before the polishing process by the automatic operation every time the wafer arrives (actually, every few lots), it is a cause of lowering the wafer throughput. It was.

  The present invention has been made in view of such problems, and provides a self-diagnosis method and a semiconductor manufacturing apparatus for a semiconductor manufacturing apparatus, a self-diagnosis method for a polishing apparatus, and a polishing apparatus capable of improving wafer throughput. The purpose is to provide.

  In order to achieve such an object, a self-diagnosis method for a semiconductor manufacturing apparatus according to the present invention is a semiconductor manufacturing apparatus that performs predetermined processing on a wafer supplied from the outside. It is determined whether or not it is in a wafer waiting state waiting for supply from the wafer, and if it is determined that it is in a wafer waiting state, whether or not a predetermined time has elapsed since it was determined that it is in a wafer waiting state If it is determined that the wafer is in a waiting state and it is determined that a predetermined time has elapsed, a self-diagnosis process is performed to detect an abnormality in the apparatus.

  In the above-described invention, it is preferable that a flow rate check process for determining whether or not the flow rate of the fluid used in the semiconductor manufacturing apparatus is appropriate is performed in the self-diagnosis process.

  In the above-described invention, it is preferable that the drive system check process for determining whether or not the drive unit for driving the semiconductor manufacturing apparatus operates properly is performed in the self-diagnosis process.

  Furthermore, the semiconductor manufacturing apparatus according to the present invention is capable of performing self-diagnosis of a device using a semiconductor manufacturing apparatus self-diagnosis method according to the present invention. It is performed.

  In addition, a self-diagnosis method for a polishing apparatus according to the present invention includes a wafer holding device that detachably holds a wafer supplied from the outside and a polishing member that can polish the wafer, and the wafer held by the wafer holding device. In a polishing apparatus configured to polish a wafer by a relative movement while a polishing member is in contact with the wafer, it is determined whether or not a wafer waiting state is waited for a wafer to be polished to be supplied from the outside. When it is determined that the wafer is waiting, it is determined whether or not a predetermined time has elapsed since the determination that the wafer is waiting is determined. The wafer is determined to be waiting and the predetermined time is determined. When it is determined that the time has elapsed, a self-diagnosis process is performed to find an abnormality in the apparatus.

  In the above-described invention, it is preferable that a flow rate check process for determining whether or not the flow rate of the fluid used in the polishing apparatus is appropriate is performed in the self-diagnosis process.

  In the above-described invention, it is preferable that the drive system check process for determining whether or not the drive unit for driving the polishing apparatus operates properly is performed in the self-diagnosis process.

  The polishing apparatus according to the present invention further includes a wafer holding device that detachably holds a wafer supplied from the outside and a polishing member that can polish the wafer, and the polishing member is attached to the wafer held by the wafer holding device. In a polishing apparatus configured to polish a wafer by relatively moving while abutting, the apparatus is self-diagnosed using the self-diagnosis method for a polishing apparatus according to the present invention.

  According to the present invention, the throughput of a wafer can be improved.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to an example in which a semiconductor wafer is applied to a CMP apparatus (chemical mechanical polishing apparatus) that precisely polishes a semiconductor wafer in a three-stage polishing process. As shown in FIG. 1 as a plan view of the overall configuration of the polishing apparatus PM, roughly, a cassette index unit 1 for carrying in (supplying) and carrying out a semiconductor wafer (hereinafter referred to as a wafer W), A polishing unit 2 that performs polishing processing, a substrate cleaning unit 3 that cleans a wafer that has been polished, and a transfer device 4 (first transfer mechanism 41 and second transfer mechanism 42) that transfer the wafer W in the polishing apparatus. Each part is partitioned by an automatic opening / closing shutter to form a clean chamber. The operation of the polishing apparatus PM is controlled by a control device 400 (see FIG. 4).

The cassette index unit 1 is provided with a wafer mounting table 12 on which cassettes (also referred to as carriers) C _{1 to} C ₄ each holding a plurality of wafers W are mounted, and in front of the wafer mounting table 12. A first transport mechanism 41 is provided. The first transport mechanism 41 is a transport device having an articulated arm, and a swivel that can be swung horizontally and moved up and down is provided on an upper part of a base that is movable along a linear guide provided on the floor. The articulated arm attached to the base is extended and contracted, and the outer peripheral edge of the wafer W can be gripped by the wafer chuck at the tip of the arm. The unprocessed unprocessed wafer W taken out from the send cassettes C ₁ and C ₂ by the first transfer mechanism 41 is polished in a passage for transferring the unprocessed wafer W provided in the substrate cleaning unit 3. Passed to the second transport mechanism 42 of the section 2.

The polishing unit 2 is divided into four areas around a circular index table 20 that is rotated and fed every 90 degrees, and a transfer stage S ₀ that carries in unprocessed wafers and carries out processed wafers. The first polishing stage S ₁ for polishing the wafer surface, the second polishing stage S ₂ , and the third polishing stage S ₃ . The index table 20 is divided into four parts corresponding to these four stages. In each section of the four divided index table 20, a wafer chuck 200 for detachably sucking and holding the wafer W from the back side is provided as a table. Exposed on the top surface.

  Each chuck 200 is rotatably supported by the index table 20, and is configured to be freely rotated at high speed and stopped and held by a driving means (not shown) such as an electric motor or an air motor provided in the index table 20. ing. The diameter of each chuck 200 is slightly smaller than the diameter of the wafer W so that the outer peripheral end of the wafer W held by the wafer chuck 200 can be gripped.

The transport stage S ₀ is provided with a second transport mechanism 42. Wafer W carried into the polishing unit 2 by the second conveying mechanism 42 is conveyed by the second conveyance mechanism 42, it is carried placed on a wafer chuck 200 which is positioned in the conveying stage S ₀ adsorbent is held.

In the first polishing stage S ₁ , the second polishing stage S ₂ , and the third polishing stage S ₃ , a surface polishing mechanism 22 that polishes the surface of the wafer W attracted and held by the wafer chuck 200 and a polishing surface of the polishing pad, respectively. And a dressing mechanism 23 for dressing.

  As shown in FIG. 2, the surface polishing mechanism 22 has a polishing pad 220, a polishing head 222 that holds and rotates the polishing surface 220s of the polishing pad in a downward horizontal posture, and the polishing head 222 swings and lifts horizontally. The polishing arm 223 to be actuated and the wafer chuck 200 for rotating the wafer W in a horizontal posture upward on the surface, etc., and the wafer surface is polished under the processing conditions corresponding to the contents of the process performed at each stage. The diameter of the polishing pad 220 is set smaller than the diameter of the wafer W to be polished.

  The wafer surface is polished by the surface polishing mechanism 22 while the polishing arm 223 is horizontally swung and the polishing head 222 is positioned above the wafer chuck. The polishing surface 220s of the polishing pad 220 is pressed against the surface (surface to be polished Ws) of the wafer W that is sucked and held and rotated, and the polishing arm 223 is swung while supplying slurry from the center of the polishing head. Thus, the entire surface of the wafer W is polished flat.

  The polishing pad 220 used in each surface polishing mechanism 22 has a processing process such as interlayer insulating film CMP and metal CMP, circuit pattern fineness, primary polishing (rough polishing) to tertiary polishing (finish polishing). An appropriate pad is selected and mounted according to the processing stage. The polishing head 222 is provided with a slurry supply structure that passes through the center and supplies the slurry to the center of the annular polishing pad 220. During the polishing process, slurry corresponding to the processing purpose is supplied from the slurry supply device. To be supplied.

  Further, a cleaning water supply device 225 (see FIG. 1) having a predetermined water supply nozzle is provided in the vicinity of the wafer chuck 200 on the wall portion of each stage, and the wafer W held by the wafer chuck 200 is provided. Cleaning water is supplied from the cleaning water supply device 225 to the surface as needed. In addition, a head rotating mechanism 226 for rotating the polishing head 222 and a head up-and-down mechanism 227 for moving the polishing head 222 up and down are built in the distal end portion of the polishing arm 223. Includes an arm swinging mechanism 228 for swinging the polishing arm 223.

  The dressing mechanism 23 includes a dressing tool 230 and a dressing vertical mechanism 231 that moves the dressing tool 230 up and down in an upward horizontal posture. Then, in a state where the polishing head 222 rotating by swinging the polishing arm 223 is moved above the dressing tool 230, the dressing tool 230 is lifted by the dressing up-and-down mechanism 231 to relatively rotate the dressing surface 230s. The polishing surface 220s is brought into contact with the polishing surface 220s of the dressing 220, and the polishing surface 220s is dressed while supplying pure water from the nozzle of the dressing water supply device 232 to the dressing processing unit to wash away grinding debris and the like.

As shown in FIG. 1, the index table 20 is rotated 90 degrees when the polishing process in the _first to third polishing stages S ₁ , S ₂ , S ₃ is completed, and is held by the wafer chuck 200 by suction. Are sequentially transferred from the transfer stage S ₀ to the first polishing stage S ₁ → the second polishing stage S ₂ → the third polishing stage S ₃ and subjected to CMP processing at each polishing stage, and polishing processing at the third polishing stage S _3. but finished wafer W is fed to the transfer stage S _0. The processed wafer W that has been sent to the transfer stage S ₀ and released from the suction and holding is transferred from the polishing unit 2 to the substrate cleaning unit 3 by the second transfer mechanism 42.

  The substrate cleaning unit 3 is composed of four chambers, a first cleaning chamber 31, a second cleaning chamber 32, a third cleaning chamber 33, and a drying chamber 34. The polishing process on both the front and back surfaces is completed, and the substrate is transferred by the second transport mechanism 42. The processed wafer W is sequentially sent to the first cleaning chamber 31-> second cleaning chamber 32-> third cleaning chamber 33-> drying chamber 34 to remove and wash the slurry and abrasive wear powder adhering to the polishing processing section 2. Is done. There are various examples of cleaning methods in each cleaning chamber. For example, in the first cleaning chamber 31, double-sided cleaning with a rotating brush, in the second cleaning chamber 32, surface pencil cleaning under ultrasonic vibration, the third cleaning chamber In 33, spinner cleaning with pure water is performed, and in the drying chamber 34, a drying process is performed in a nitrogen atmosphere. A passage for transferring the unprocessed wafer W is provided below the first cleaning chamber 31.

The processed wafer W cleaned by the substrate cleaning unit 3 is taken out of the substrate cleaning unit by the first transport mechanism 41 and is placed in a predetermined slot of the receive cassettes C ₃ and C ₄ mounted on the wafer mounting table 12, or It is accommodated in the empty slots of the send cassettes C ₁ and C ₂ .

Next, a method for polishing the wafer W using the polishing apparatus PM configured as described above will be described with reference to FIG. Here, FIG. 3 shows that the unprocessed wafers W accommodated in the send cassette C ₁ of the cassette index unit 1 are sequentially polished by the polishing unit 2 and cleaned by the substrate cleaning unit 3. the flow of the wafer W to be housed in the receive cassette C ₄ illustrates denoted by the dotted arrow. The operation of the polishing apparatus PM is controlled by a control device 400 (see FIG. 4), and the control device controls the operation of each unit based on a preset control program.

When the polishing processing program is started by the polishing apparatus PM, the first transport mechanism 41 moves to the position of the send cassette C ₁ , horizontally swings and lifts the swivel, and expands the articulated arm to move the wafer chuck. The unprocessed wafer W in the slot is taken out, and the swivel base is turned 180 degrees to go to a passage installed below the first cleaning chamber 31, and the second transfer mechanism 42 on the polishing processing unit 2 side in this passage. The unprocessed wafer W is delivered to

The second transfer mechanism 42 that has received the unprocessed wafer W from the first transfer mechanism 41 carries the unprocessed wafer W into the polishing unit 2. The raw wafer W is transferred to the second transport mechanism 42 by surface polishing mechanism 22, is carried placed on the wafer chuck 200 of the conveying stage S ₀ positioned stopped index table 20. When the wafer W is placed, the wafer chuck 200 holds the back surface of the wafer W by vacuum suction, and the second transfer mechanism 42 retracts.

Polishing is started in the first polishing stage S ₁ to the third polishing stage S ₃ of the surface polishing mechanism 22. Since the wafer surface polishing performed in such a three-stage polishing stage is already known (for example, Japanese Patent Application Laid-Open No. 2002-93759 by the present applicant), detailed description thereof is omitted in this specification. The following is a brief description.

When the second transport mechanism 42 is retracted, the index table 20 is positioned suction-held wafer W is in a first polishing stage S ₁ the wafer chuck 200 is rotated 90 degrees clockwise, the polishing arm 223 simultaneously swing As a result, the polishing head 222 moves onto the wafer. Then, the polishing head 222 and the wafer chuck 200 start to rotate in opposite directions and the polishing head 222 descends to press the polishing pad 220 (polishing surface) against the wafer surface (surface to be polished) to perform the primary polishing process. . During the polishing process, the polishing arm 223 is swung so that the polishing pad 220 reciprocates between the rotation center and the outer peripheral end of the wafer while supplying slurry from the axis of the polishing head 222, and the wafer surface is moved. Uniform flat polishing.

When the first polishing process is completed, the control device further rotates the index table 20 by 90 degrees clockwise, and waits for the wafer after the first polishing process to the second polishing stage S ₂ at the transfer stage S ₀ . positioning the wafer formed in the first polishing stage S _1. Then, the polishing head 222 is lowered at the first and second polishing stages, respectively, and the first polishing process and the second polishing process are simultaneously performed in parallel.

When the second polishing process is finished, the control device checks whether or not the first polishing process is finished, and when the first polishing process is finished, the control unit further turns the index table 20 90 degrees clockwise. The wafers that have been rotated and turned to the third polishing stage S ₃ are finished with the second polishing process, the second polishing stage S ₂ is the wafer that has finished the first polishing process, and the wafers that are waiting on the transfer stage are turned to the second polishing stage S ₂ . 1 positioned in the polishing stage S _1, lowers the polishing head 222, respectively, first, second, to take such a third-order polished simultaneously.

When the third polishing process is completed, the control device checks whether or not the first polishing process and the second polishing process have been completed. further by 90 degrees rotation around the conveying stage S ₀ wafers tertiary polishing it is finished, even a wafer positioned at other stages positioning is moved by the first stage in the same manner as described above.

When the positioning of the index table 20 is stopped and the wafer whose surface polishing is finished through the first to third polishing stages is positioned on the transfer stage S ₀ , the second transfer mechanism 42 is released from the vacuum chucking on the wafer chuck 200. The outer peripheral edge of the processed wafer is gripped and lifted and swiveled, moved horizontally along the linear guide, and transferred to the substrate cleaning unit 3. In addition, after the processed wafer is transferred, an unprocessed wafer is received from the first transfer mechanism 41 and carried into the polishing processing unit 2.

In the substrate cleaning unit 3, double-sided cleaning with a rotating brush in the first cleaning chamber 31, surface pencil cleaning under ultrasonic vibration in the second cleaning chamber 32, spinner cleaning with pure water in the third cleaning chamber 33, and the drying chamber 34. The drying process is performed in a nitrogen atmosphere. The finished product wafer that has been cleaned in this way is removed from the substrate cleaning unit 3 by the first conveyance mechanism 41 of the cassette index portion 1 is accommodated in the specified slot from the receive cassette C _4.

The above operation is sequentially repeated, and after the polishing of the first wafer is completed, the wafer whose front and back surfaces are polished flat is stored in the cassette C ₄ at every rotation interval of the index table 20. . The rotation interval of the index table 20 is defined by the polishing time divided into three stages. For example, a completed wafer is continuously produced at each time interval of the first polishing process. In addition, dressing by the dressing mechanism 23 is performed each time before each polishing process is performed in each polishing stage, and the clogging of the polishing pad surface (polishing surface 220s) is corrected to ensure flatness.

  By the way, in the polishing apparatus PM, a self-diagnosis for finding an abnormality in the apparatus is performed before the polishing process as described above is started. Specifically, in the self-diagnosis process, the flow rate check process for determining whether or not the flow rate of the fluid used in the polishing apparatus PM is appropriate, and whether the drive unit for driving the polishing apparatus PM operates properly. A drive system check process for determining whether or not is performed is performed. In the present embodiment, the fluid to be subjected to the flow rate check process is pure water used in the cleaning water supply device 225 and the dressing water supply device 232 and nitrogen gas used in the drying chamber 34. The drive units that are the targets of the drive system check process are the head vertical mechanism 227, the arm swing mechanism 228, and the dressing vertical mechanism 231.

  FIG. 4 shows a part of a control system in the polishing apparatus PM. The control device 400 is configured to output control signals to the cassette index unit 1, the polishing processing unit 2, the substrate cleaning unit 3, the transfer device 4, and the like to control the operation of each device. Shows the components that are the targets of the flow rate check process and the drive system check process.

  As shown in FIG. 4, the cleaning water supply device 225 is connected to a pure water supply unit 401 provided outside the polishing apparatus PM via a pipe, and pure water is supplied from the pure water supply unit 401 to the cleaning water supply device 225. Water is supplied. A first fluid control valve 410 and a first flow meter 411 are disposed in a pipe line connecting the cleaning water supply device 225 and the pure water supply unit 401. The first fluid control valve 410 is electrically connected to the control device 400, and performs opening / closing control of the valve in accordance with a control signal from the control device 400. The first flow meter 411 is electrically connected to the control device 400, and outputs the flow rate of pure water supplied from the pure water supply unit 401 to the cleaning water supply device 225 to the control device 400.

  The dressing water supply device 232 is connected to the pure water supply unit 401 in the same manner as the cleaning water supply device 225, and pure water is supplied from the pure water supply unit 401 to the dressing water supply device 232. A second fluid control valve 412 and a second flow meter 413 are disposed in a pipe line connecting the dressing water supply device 232 and the pure water supply unit 401. The second fluid control valve 412 is electrically connected to the control device 400 and performs opening / closing control of the valve in accordance with a control signal from the control device 400. The second flow meter 413 is electrically connected to the control device 400, and outputs the flow rate of pure water supplied from the pure water supply unit 401 to the dressing water supply device 232 to the control device 400.

  The drying chamber 34 is connected to a nitrogen supply unit 402 (such as a nitrogen gas cylinder) provided outside the polishing apparatus PM via a pipe so that nitrogen gas is supplied from the nitrogen supply unit 402 to the drying chamber 34. It has become. A third fluid control valve 414 and a third flow meter 415 are disposed in a pipe line connecting the drying chamber 34 and the nitrogen supply unit 402. The third fluid control valve 414 is electrically connected to the control device 400 and performs opening / closing control of the valve in accordance with a control signal from the control device 400. The third flow meter 415 is electrically connected to the control device 400 and outputs the flow rate of nitrogen gas supplied from the nitrogen supply unit 402 to the drying chamber 34 to the control device 400.

  Further, the head vertical mechanism 227, the arm swing mechanism 228, and the dressing vertical mechanism 231 are electrically connected to the control device 400. The head up-and-down mechanism 227 includes an air cylinder (not shown) for moving the polishing head 222 up and down, an electropneumatic regulator (not shown), and the like from the control device 400 (to the electropneumatic regulator etc.). The operation of the head up / down mechanism 227 is controlled in accordance with the output control signal. In the vicinity of the polishing head 222 in the polishing arm 223, a head lift sensor 420 that detects whether or not the polishing head 222 is positioned at a predetermined head lift position, and the polishing head 222 below the head lift position. A head lowering sensor 421 is provided for detecting whether or not the head lowering position is located at a predetermined head lowering position, and a detection signal of each sensor is output to the control device 400.

  The arm swing mechanism 228 includes an electric motor (not shown) for swinging the polishing arm 223 and the like, and the head according to a control signal output from the control device 400 (to the electric motor or the like). The operation of the vertical mechanism 227 is controlled. In the vicinity of the polishing arm 223, a first swing sensor 422 that detects whether the polishing arm 223 is located at a predetermined first swing position close to the wafer chuck 200 side, and the polishing arm 223 includes a dressing mechanism. A second swing sensor 423 is provided for detecting whether or not the second swing sensor 423 is positioned at a predetermined second swing position close to the 23 side, and a detection signal of each sensor is output to the control device 400. .

  The dressing up-and-down mechanism 231 includes an air cylinder (not shown) for moving the dressing tool 230 up and down, an electropneumatic regulator (not shown), and the like from the control device 400 (to the electropneumatic regulator etc.). The operation of the dressing up / down mechanism 231 is controlled in accordance with the output control signal. In the vicinity of the dressing tool 230, a dressing ascent sensor 424 for detecting whether or not the dressing tool 230 is located at a predetermined tool ascending position, and a predetermined position where the dressing tool 230 is located below the tool ascending position. A dressing lowering sensor 425 for detecting whether or not the tool is in the tool lowering position is provided, and a detection signal of each sensor is output to the control device 400.

  Now, such a self-diagnosis method of the polishing apparatus PM will be described below with reference to the flowchart shown in FIG. Each process described below is performed by the control device 400 unless otherwise described. First, in step S101, an environment holding start timer for performing an environment holding process to be described later is cleared (set to 0), and a self-diagnosis executed flag that is set when the self-diagnosis process is executed is cleared.

  Next, in step S102, whether or not the wafer W (cassette) for performing the polishing process has arrived at the wafer mounting table 12, that is, is the wafer waiting state waiting for the wafer W to be supplied from the outside? Determine whether or not. When the wafer W has arrived (in the case of Yes), it is determined that the wafer is not in a waiting state, and the processing is completed, and polishing of the wafer W by the polishing apparatus PM is started with a predetermined recipe. On the other hand, if the wafer W has not arrived (in the case of No), it is determined that the wafer is waiting and the process proceeds to step S103.

  In step S103, it is determined whether or not the environment maintenance activation timer has passed a specified time. Note that the specified time is a time that is set as appropriate in order to perform the environment maintenance process periodically. If the specified time has not elapsed (No), the process returns to Step S102, and if the specified time has elapsed (Yes), the process proceeds to Step S104.

In step S104, an environment holding process for keeping the environment in the apparatus constant is executed. In the environment maintaining process, for example, a moisture retaining process for the polishing pad 220 is performed. Note that the moisturizing process of the polishing pad 220 is performed by filling a pad exchange table (not shown) disposed in each of the polishing stages S _{1 to} S ₃ with pure water and using the polishing arm 223 to polish the polishing pad 220 (polishing head 222. ) Is moved to the pad exchange table, and a part of the polishing pad 220 is brought into contact with a portion filled with pure water in the pad exchange table. When the environment maintenance process is completed, the environment maintenance activation timer is cleared and the process proceeds to step S105.

  In step S105, it is determined whether or not the self-diagnosis process has been executed, that is, whether or not the self-diagnosis executed flag has been set. If the self-diagnosis process has been executed (in the case of Yes), the process returns to step S102. If the self-diagnosis process has not been executed (in the case of No), the process proceeds to step S106.

  In step S106, a self-diagnosis process for detecting an abnormality in the apparatus is executed, and the process returns to step S102. At this time, when the self-diagnosis process is completed, the self-diagnosis executed flag is set. As can be seen from the above, the self-diagnosis process is executed after the environment maintenance start timer has passed the specified time and the environment maintenance process is executed. In step S101, the environment maintenance start timer and the self-diagnosis executed flag are cleared. Therefore, the self-diagnosis is performed after a predetermined time (approximately equal to the time obtained by adding the processing time of the environmental holding process to the specified time of the environmental holding start timer) has elapsed since it was actually determined that the wafer is waiting. Processing will be executed.

  As described above, in the self-diagnosis process, the flow rate check process and the drive system check process are performed. First, the flow rate check process will be described below with reference to the flowchart shown in FIG. In the flow rate check process, first, in step S201, the valve of the fluid to be investigated is opened. In this embodiment, when the investigation target is pure water used in the cleaning water supply device 225, the first fluid control valve 410 is opened. Similarly, when the investigation target is pure water used in the dressing water supply device 232, the second fluid control valve 412 is opened. Similarly, when the investigation target is nitrogen gas used in the drying chamber 34, the third fluid control valve 414 is opened.

  Next, in step S202, the flow rate of the fluid to be investigated is monitored at regular intervals (for example, 10 seconds) and at regular intervals (for example, every 0.2 seconds). At this time, when the investigation target is pure water used in the cleaning water supply device 225, the flow rate of pure water is measured by the first flow meter 411. Similarly, when the investigation target is pure water used in the dressing water supply device 232, the flow rate of pure water is measured by the second flow meter 413. Similarly, when the investigation object is nitrogen gas used in the drying chamber 34, the flow rate of nitrogen gas is measured by the third flow meter 415.

  Next, in step S203, the valve of the fluid to be investigated is closed. At this time, when the investigation target is pure water used in the cleaning water supply device 225, the first fluid control valve 410 is closed. Similarly, when the investigation target is pure water used in the dressing water supply device 232, the second fluid control valve 412 is closed. Similarly, when the investigation object is nitrogen gas used in the drying chamber 34, the third fluid control valve 414 is closed.

  Next, in step S204, it is determined whether the time-series flow rate of the fluid acquired in step S202 is an appropriate value. Specifically, the following three items are determined. First, it is determined whether or not the fluid flow rate is within a specified flow rate range. Second, it is determined whether the time from opening the valve to reaching the specified flow rate is appropriate. Third, it is determined whether or not the flow rate fluctuation after reaching the specified flow rate is appropriate.

  Next, in step S205, it is determined whether the flow rate is normal or abnormal. Specifically, when it is determined that the flow rate is appropriate for all items in step S204, it is determined that the flow rate of the fluid to be investigated is normal. On the other hand, if it is determined that the flow rate is not appropriate for all items in step S204, the flow rate of the fluid to be investigated is determined to be abnormal, and an alarm operation such as an alarm is performed.

  In step S206, it is determined whether or not the flow rates of all the fluids to be investigated (that is, the flow rates of each pure water and nitrogen gas) have been checked. If the determination result is No, the process returns to step S201, and if the determination result is Yes, the flow rate check process ends.

  Next, the drive system check process will be described below with reference to the flowchart shown in FIG. In the drive system check process, first, in step S301, the drive unit to be investigated is driven to obtain the drive time. Specifically, when the investigation target is the head up / down mechanism 227, the head up / down mechanism 227 is driven to lower the polishing head 222 from the head raised position to the head lowered position, and the polishing head 222 moves from the head raised position. Get the time to reach the head down position. At this time, the position of the polishing head 222 (head raised position and head lowered position) is detected by the head rising sensor 420 and the head lowering sensor 421.

  Similarly, when the investigation target is the arm swing mechanism 228, the arm swing mechanism 228 is driven to swing the polishing arm 223 from the first swing position to the second swing position, and the polishing arm 223 is driven. Is acquired from the first swing position to the second swing position. At this time, the position (first swing position and second swing position) of the polishing arm 223 is detected by the first swing sensor 422 and the second swing sensor 423.

  Similarly, when the object to be investigated is the dressing up-and-down mechanism 231, the dressing up-and-down mechanism 231 is driven to raise the dressing tool 230 from the tool lowered position to the tool raised position, and the polishing head 222 moves from the tool lowered position to the tool. Get the time to reach the ascending position. At this time, the position of the polishing head 222 (tool rising position and tool lowering position) is detected by the dressing ascending sensor 424 and the dressing descending sensor 425.

  Next, in step S302, the drive unit is driven in the direction opposite to that in step S301, and the drive time is acquired. Specifically, when the investigation target is the head up-and-down mechanism 227, the polishing head 222 is raised from the head lowered position to the head raised position, and the time for the polishing head 222 to reach from the head lowered position to the head raised position is acquired. Similarly, when the object to be investigated is the arm swing mechanism 228, the polishing arm 223 is swung from the second swing position to the first swing position, and the polishing arm 223 is moved from the second swing position to the first swing position. Get the time to reach. Similarly, when the investigation target is the dressing up / down mechanism 231, the dressing tool 230 is lowered from the tool raised position to the tool lowered position, and the time for the polishing head 222 to reach from the tool raised position to the tool lowered position is acquired.

  Next, in step S303, the operations in steps S301 and S302 are repeated a plurality of times (for example, 10 times).

  Next, in step S304, it is determined whether or not the driving time of the driving unit acquired in each step is an appropriate value. Specifically, the following three items are determined. First, it is determined whether or not the minimum value of the driving time is within a specified range. Secondly, it is determined whether or not the maximum value of the driving time is within a specified range. Third, it is determined whether or not the average value of the driving time is within a specified range.

  Next, in step S305, normality / abnormality of the drive unit to be investigated is determined. Specifically, when it is determined that the drive time is appropriate for all items in step S304, it is determined that the drive unit to be investigated is normal. On the other hand, if it is determined that even one of the items in step S304 is not suitable for the driving time, the driving unit to be investigated is determined to be abnormal, and an alarm operation such as an alarm is performed.

  In step S306, it is determined whether or not all the drive units to be investigated (that is, the head vertical mechanism 227, arm swing mechanism 228, and dressing vertical mechanism 231) have been checked. If the determination result is No, the process returns to step S301. If the determination result is Yes, the process ends.

  If it is determined that the wafer W (cassette) for performing the polishing process has arrived and is not in a wafer waiting state, the self-diagnosis process described above is performed immediately before the polishing process is started, and a polishing apparatus is used with a predetermined recipe. The polishing process of the wafer W by PM is started. At this time, if the self-diagnosis process has been executed in the wafer waiting state, the self-diagnosis process performed immediately before the polishing process is started is omitted.

  As a result, according to the self-diagnosis method and the polishing apparatus of the polishing apparatus according to the present embodiment, the self-diagnosis process immediately after the wafer W (cassette) arrives can be performed by executing the self-diagnosis process while waiting for the wafer. Since this can be omitted, the throughput of the wafer W can be improved. In addition, since the self-diagnosis process is executed when the wafer is waiting, an abnormality in the apparatus can be detected early. Furthermore, since the device performs self-diagnosis, the operator's trouble can be saved.

  Further, by performing the flow rate check process in the self-diagnosis process, it is possible to quickly find an abnormality in the flow rate of the fluid (each pure water and nitrogen gas) used in the polishing apparatus PM.

  Further, by performing the drive system check process in the self-diagnosis process, it is possible to quickly find an abnormality in the drive units (the head vertical mechanism 227, the arm swinging mechanism 228, and the dressing vertical mechanism 231) constituting the polishing apparatus PM. .

  In the above-described embodiment, the polishing apparatus PM that polishes the wafer W is described as an example. However, the present invention is not limited to this. For example, an exposure apparatus (stepper) that transfers a predetermined mask pattern to the wafer. The present invention can also be applied to a semiconductor manufacturing apparatus that performs a predetermined process on a wafer supplied from the outside.

  In the above-described embodiment, the self-diagnosis process is executed after the environment holding process is executed. However, the present invention is not limited to this, and the self-diagnosis is performed during the environment holding process (or simultaneously with the environment holding process). Processing may be executed.

  Furthermore, in the above-described embodiment, the fluids to be subjected to the flow rate check process are pure water used in the cleaning water supply device 225 and the dressing water supply device 232 and nitrogen gas used in the drying chamber 34. For example, such a process can be performed on a fluid used in the polishing apparatus PM, such as air or slurry used in an air cylinder (not shown) of the head vertical mechanism 227.

  In the above-described embodiment, the drive units that are the targets of the drive system check process are the head vertical mechanism 227, the arm swinging mechanism 228, and the dressing vertical mechanism 231, but are not limited thereto. Such processing can be performed on a driving unit for driving the polishing apparatus PM, such as a head rotating mechanism 226 for rotating the polishing head 222.

It is a top view which shows the example of whole structure of a grinding | polishing apparatus. It is a schematic block diagram which shows a surface polishing mechanism and a dressing mechanism typically. It is explanatory drawing which shows the flow of the wafer in a grinding | polishing apparatus. It is a block diagram which shows a part of control system in a grinding | polishing apparatus. It is a flowchart which shows the self-diagnosis method of a grinding | polishing apparatus. It is a flowchart which shows a flow volume check process. It is a flowchart which shows a drive system check process.

Explanation of symbols

PM polishing equipment (semiconductor manufacturing equipment)
W Wafer Ws Surface to be polished 22 Surface polishing mechanism 34 Drying chamber 200 Wafer chuck (wafer holding device)
220 polishing pad (polishing member) 222 polishing head 223 polishing arm 225 cleaning water supply device 227 head vertical mechanism 228 arm swing mechanism 230 dressing tool 231 dressing vertical mechanism 232 dressing water supply device 400 controller 401 pure water supply unit 402 nitrogen supply Part

Claims (8)

In a semiconductor manufacturing apparatus that performs predetermined processing on a wafer supplied from the outside,
Determining whether or not a wafer waiting state for waiting for a wafer for performing the predetermined processing to be supplied from the outside;
When it is determined that the wafer is in a waiting state, it is determined whether a predetermined time has elapsed since it was determined that the wafer is in a waiting state;
A self-diagnosis method for a semiconductor manufacturing apparatus, comprising: performing a self-diagnosis process for finding an abnormality in an apparatus when it is determined that the wafer is in a waiting state and the predetermined time has elapsed.   2. The self-diagnosis method for a semiconductor manufacturing apparatus according to claim 1, wherein in the self-diagnosis process, a flow rate check process for determining whether or not a flow rate of a fluid used in the semiconductor manufacturing apparatus is appropriate is performed. .   3. The drive system check process for determining whether or not a drive unit for driving the semiconductor manufacturing apparatus operates properly in the self-diagnosis process is performed according to claim 1. Self-diagnosis method for semiconductor manufacturing equipment. In a semiconductor manufacturing apparatus that performs predetermined processing on a wafer supplied from the outside,
4. A semiconductor manufacturing apparatus, wherein the self-diagnosis of the apparatus is performed using the self-diagnosis method of the semiconductor manufacturing apparatus according to any one of claims 1 to 3. A wafer holding device that detachably holds a wafer supplied from the outside and a polishing member that can polish the wafer, and relatively moves the polishing member in contact with the wafer held by the wafer holding device. In a polishing apparatus configured to polish the wafer,
Determining whether or not a wafer waiting state for waiting for a wafer to be polished to be supplied from outside;
When it is determined that the wafer is in a waiting state, it is determined whether a predetermined time has elapsed since it was determined that the wafer is in a waiting state;
A self-diagnosis method for a polishing apparatus, comprising: performing a self-diagnosis process for finding an abnormality of the apparatus when it is determined that the wafer is in a waiting state and the predetermined time has elapsed.   6. The self-diagnosis method for a polishing apparatus according to claim 5, wherein in the self-diagnosis process, a flow rate check process for determining whether or not a flow rate of a fluid used in the polishing apparatus is appropriate is performed.   The polishing according to claim 5 or 6, wherein in the self-diagnosis process, a drive system check process for determining whether or not a drive unit for driving the polishing apparatus operates properly is performed. Device self-diagnosis method. A wafer holding device that detachably holds a wafer supplied from the outside and a polishing member that can polish the wafer, and relatively moves the polishing member in contact with the wafer held by the wafer holding device. In a polishing apparatus configured to polish the wafer,
A polishing apparatus, wherein the apparatus is self-diagnosed using the polishing apparatus self-diagnosis method according to any one of claims 5 to 7.

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