SUBSTRATE PROCESSING APPARATUS AND ABNORMALITY DETECTION METHOD

Abstract

To provide a substrate processing apparatus and an abnormality detection method that monitors whether a processed substrate is being absorbed by the electrostatic chuck with sufficient suction force.SOLUTION: In a semiconductor manufacturing equipment, a substrate processing apparatus 5 comprises a mounting table 60 having an electrostatic chuck 65 that adsorbs substrates, a heating unit 63 that heats the mounting table, a heating drive unit 71 that supplies electric power to the heating unit to make the temperature of the mounting table a target value, and a detection unit that detects abnormalities in adsorption of the substrate by the electrostatic chuck. A control unit 4 as the detection unit detects the abnormality based on fluctuations in the electric power supplied to the heating unit caused by the adsorption of the substrate by the electrostatic chuck.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a substrate processing apparatus and an abnormality detection method. [Background technology]

[0002] 2. Description of the Related Art In a substrate processing apparatus used in a semiconductor manufacturing device, an electrostatic chuck is used to hold a substrate to be processed (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6611666 Summary of the Invention [Problem to be solved by the invention]

[0004] If the processing substrate is not attracted to the electrostatic chuck with sufficient attracting force, the temperature of the processing substrate may not be controlled normally.

[0005] The present disclosure provides a technique for monitoring whether a processing substrate is being attracted to an electrostatic chuck with sufficient attraction force. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, there is provided a substrate processing apparatus comprising: a mounting table having an electrostatic chuck for adsorbing a substrate; a heating unit for heating the mounting table; a heating drive unit for supplying power to the heating unit so as to bring the temperature of the mounting table to a target value; and a detection unit for detecting an abnormality in the adsorption of the substrate by the electrostatic chuck, wherein the detection unit detects the abnormality based on a fluctuation in the power supplied to the heating unit caused by the adsorption of the substrate by the electrostatic chuck. Effect of the Invention

[0007] According to the present disclosure, it is possible to monitor whether the processing substrate is attracted to the electrostatic chuck with sufficient attracting force. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic cross-sectional view of an example of a semiconductor manufacturing apparatus according to this embodiment. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing an example of a wafer transport path in the semiconductor manufacturing apparatus according to this embodiment. [Diagram 3] FIG. 3 is a schematic cross-sectional view of an example of a substrate processing apparatus of a semiconductor manufacturing apparatus according to the first embodiment. [Figure 4] FIG. 4 is a flowchart showing an example of an abnormality detection method for the substrate processing apparatus of the semiconductor manufacturing apparatus according to the first embodiment. [Diagram 5] FIG. 5 is a diagram illustrating an example of a method for detecting an abnormality in a substrate processing apparatus of a semiconductor manufacturing apparatus according to the first embodiment. [Figure 6] FIG. 6 is a diagram illustrating an example of a method for detecting an abnormality in a substrate processing apparatus of a semiconductor manufacturing apparatus according to the first embodiment. [Figure 7] FIG. 7 is a diagram illustrating an example of a method for detecting an abnormality in a substrate processing apparatus of a semiconductor manufacturing apparatus according to the first embodiment. [Figure 8] FIG. 8 is a diagram illustrating an example of a method for detecting an abnormality in a substrate processing apparatus of a semiconductor manufacturing apparatus according to the first embodiment. [Figure 9] FIG. 9 is a diagram illustrating an example of a method for detecting an abnormality in a substrate processing apparatus of a semiconductor manufacturing apparatus according to the first embodiment. [Figure 10] FIG. 10 is a diagram illustrating an example of a method for detecting an abnormality in a substrate processing apparatus of a semiconductor manufacturing apparatus according to the second embodiment. [Figure 11] FIG. 11 is a diagram illustrating an example of a method for evaluating the performance of the abnormality detection method for a substrate processing apparatus of a semiconductor manufacturing apparatus according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments of the present disclosure will be described with reference to the drawings. In this specification and the drawings, the same reference numerals are used to designate substantially the same components, and redundant description will be omitted. In order to facilitate understanding, the scale of each part in the drawings may differ from the actual scale.

[0010] In the directions of parallel, right angle, orthogonal, horizontal, vertical, up / down, left / right, etc., deviations are permitted to the extent that they do not impair the effects of the embodiment. The shape of the corners is not limited to right angles and may be rounded in an arch shape. Parallel, right angle, orthogonal, horizontal, and vertical may include approximately parallel, approximately right angle, approximately orthogonal, approximately horizontal, and approximately vertical.

[0011] <<First embodiment>> <Semiconductor manufacturing equipment 1> 1 is a schematic cross-sectional view of a semiconductor manufacturing apparatus 1, which is an example of a semiconductor manufacturing apparatus according to this embodiment. The semiconductor manufacturing apparatus 1 performs a plurality of processes (desired processes such as etching, film formation, ashing, etc.) on a substrate W. The semiconductor manufacturing apparatus 1 includes a processing section 2, a loading / unloading section 3, and a control section 4. The substrate W is not particularly limited, but is, for example, a semiconductor wafer (hereinafter simply referred to as a wafer).

[0012] The load / unload unit 3 loads and unloads substrates, such as wafers, into and out of the processing unit 2. The processing unit 2 includes a plurality of process modules PM1-PM10 (ten in this embodiment) that perform desired vacuum processing on the wafers. Wafers are serially transferred (sequentially transferred) to the plurality of process modules PM1-PM10 by a first transfer device 11.

[0013] The first transfer device 11 includes a plurality of transfer modules TM1 to TM5. The transfer modules TM1 to TM5 include containers 30a, 30b, 30c, 30d, and 30e, each of which has a hexagonal planar shape and is held in a vacuum. The transfer modules TM1 to TM5 also include transfer mechanisms 31a, 31b, 31c, 31d, and 31e, each of which has an articulated structure, provided in the containers 30a, 30b, 30c, 30d, and 30e, respectively.

[0014] Between the transfer mechanisms 31a, 31b, 31c, 31d, and 31e of the transfer modules TM1 to TM5, there are provided transfer units 41, 42, 43, and 44 as transfer buffers. The containers 30a, 30b, 30c, 30d, and 30e of the transfer modules TM1 to TM5 are connected to each other to form one transfer chamber 12.

[0015] The transfer chamber 12 extends in the Y direction in the figure. Five process modules PM1-PM10 are connected to each side of the transfer chamber 12 via openable and closable gate valves G. The gate valves G of the process modules PM1-PM10 are opened when the transfer modules TM1-TM5 access the process modules PM1-PM10, and are closed when the desired processing is being performed.

[0016] The loading / unloading section 3 is connected to one end side of the processing section 2. The loading / unloading section 3 has an atmospheric transfer chamber 21, three load ports 22, an aligner module 23, two load lock modules LLM1 and LLM2, and a second transfer device 24. The load port 22, the aligner module 23, and the load lock modules LLM1 and LLM2 are connected to the atmospheric transfer chamber 21. The second transfer device 24 is provided inside the atmospheric transfer chamber 21.

[0017] The atmospheric transfer chamber 21 has a rectangular parallelepiped shape with the X direction in the figure as the longitudinal direction. The three load ports 22 are provided on the long side wall of the atmospheric transfer chamber 21 opposite the processing section 2. The load port 22 has a mounting table 25 and a transfer port 26. A FOUP 20, which is a substrate storage container that stores a plurality of wafers, is placed on the mounting table 25. The FOUP 20 on the mounting table 25 is connected to the atmospheric transfer chamber 21 in a sealed state via the transfer port 26. The aligner module 23 is connected to one of the short side walls of the atmospheric transfer chamber 21. Wafer alignment is performed in the aligner module 23.

[0018] The two load lock modules LLM1 and LLM2 are intended to enable the transfer of wafers between the atmospheric transfer chamber 21, which is at atmospheric pressure, and the transfer chamber 12, which is at a vacuum atmosphere, and are capable of varying the pressure between atmospheric pressure and a vacuum equivalent to that of the transfer chamber 12. Each of the two load lock modules LLM1 and LLM2 has two transfer ports. One of the transfer ports is connected to the long side wall of the atmospheric transfer chamber 21 on the processing section 2 side via a gate valve G2. The other transfer port is connected to the transfer chamber 12 of the processing section 2 via a gate valve G1.

[0019] The load lock module LLM1 is used when transferring a wafer from the load / unload section 3 to the processing section 2. The load lock module LLM2 is used when transferring a wafer from the processing section 2 to the load / unload section 3. Note that the load lock modules LLM1 and LLM2 may be configured to perform processing such as degassing.

[0020] The second transfer device 24 in the atmospheric transfer chamber 21 has an articulated structure and transfers wafers to the FOUP 20 on the load port 22, the aligner module 23, and the load lock modules LLM1 and LLM2. Specifically, the second transfer device 24 takes out an unprocessed wafer from the FOUP 20 on the load port 22, transfers it to the aligner module 23, and transfers the wafer from the aligner module 23 to the load lock module LLM1. The second transfer device 24 also receives a processed wafer transferred from the processing unit 2 to the load lock module LLM2, and transfers it to the FOUP 20 on the load port 22. FIG. 1 shows an example in which the second transfer device 24 has one pick for receiving a wafer, but two picks may be used.

[0021] The first transfer device 11 and the second transfer device 24 constitute a transfer section of the semiconductor manufacturing equipment 1. In the processing section 2, process modules PM1, PM3, PM5, PM7, and PM9 are arranged in order from the load lock module LLM1 side on one side of the transfer chamber 12. In the processing section 2, process modules PM2, PM4, PM6, PM8, and PM10 are arranged in order from the load lock module LLM2 side on the other side of the transfer chamber 12. In the first transfer device 11, transfer modules TM1, TM2, TM3, TM4, and TM5 are arranged in order from the load lock modules LLM1 and LLM2 sides.

[0022] The transfer mechanism 31a of the transfer module TM1 is accessible to the load lock modules LLM1 and LLM2, the process modules PM1 and PM2, and the transfer unit 41. The transfer mechanism 31b of the transfer module TM2 is accessible to the process modules PM1, PM2, PM3, and PM4, and the transfer units 41 and .

[0023] The transfer mechanism 31c of the transfer module TM3 is accessible to the process modules PM3, PM4, PM5, and PM6, as well as the transfer sections 42 and 43. The transfer mechanism 31d of the transfer module TM4 is accessible to the process modules PM5, PM6, PM7, and PM8, as well as the transfer sections 43 and 44. The transfer mechanism 31e of the transfer module TM5 is accessible to the process modules PM7, PM8, PM9, and PM10, as well as the transfer section 44.

[0024] The second transfer device 24 and the transfer modules TM1 to TM5 of the first transfer device 11 are configured as shown in Fig. 1. For this reason, as shown in Fig. 2, wafers taken out from FOUP 20 are serially transferred in one direction along a substantially U-shaped path P in the processing section 2, processed in each of the process modules PM1 to PM10, and returned to FOUP 20. That is, the wafers are serially transferred in the order of the process modules PM1, PM3, PM5, PM7, PM9, PM10, PM8, PM6, PM4, and PM2, and subjected to the desired processing.

[0025] The semiconductor manufacturing apparatus 1 can be used, for example, to manufacture a stacked film (Magnetoresistive Tunnel Junction (MTJ) film) used in a Magnetoresistive Random Access Memory (MRAM). The manufacture of an MTJ film involves a number of desired processes, such as a pre-cleaning process, a film formation process, an oxidation process, a heating process, and a cooling process, and each of these desired processes is performed in the process modules PM1 to PM10. One or more of the process modules PM1 to PM10 may be a standby module for holding a wafer on standby.

[0026] The control unit 4 controls each component of the semiconductor manufacturing equipment 1. The control unit 4 controls, for example, the transfer modules TM1-TM5 (transfer mechanisms 31a-31e), the second transfer device 24, the process modules PM1-PM10, the load lock modules LLM1 and LLM2, the transfer chamber 12, and the gate valves G, G1, and G2. The control unit 4 is, for example, a computer.

[0027] <Substrate processing device 5> Next, a description will be given of the substrate processing apparatus 5 used in any one of the process modules PM1 to PM10. Fig. 3 is a schematic cross-sectional view of the substrate processing apparatus 5, which is an example of the substrate processing apparatus of the semiconductor manufacturing apparatus according to this embodiment.

[0028] The substrate processing apparatus 5 includes a mounting table 60 for mounting a substrate W thereon, disposed inside a processing chamber 50. The mounting table 60 includes a base portion 62 and an electrostatic chuck 65.

[0029] The base portion 62 is made of, for example, aluminum and has a substantially disk shape.

[0030] The electrostatic chuck 65 is provided on the upper surface of the base portion 62. The electrostatic chuck 65 holds the substrate W by electrostatic adsorption force. The electrostatic chuck 65 has an electrode 66 formed of a conductive film. The electrode 66 is sandwiched between dielectric films 67. A DC power supply 72 is connected to the electrode 66 of the electrostatic chuck 65. The electrostatic chuck 65 adsorbs and holds the substrate W on the electrostatic chuck 65 by electrostatic force due to a voltage applied from the DC power supply 72.

[0031] The base portion 62 includes therein a heating portion 63, which is, for example, an electric heater. The base portion 62 also includes therein a temperature sensor 64 that detects the temperature of the base portion 62. The temperature sensor 64 is, for example, a thermocouple or a resistance temperature detector.

[0032] The heating unit 63 is connected to the heating drive unit 71. The heating drive unit 71 supplies power to the heating unit 63. The heating unit 63 supplied with power from the heating drive unit 71 heats the base unit 62. The base unit 62 is heated, thereby heating the electrostatic chuck 65. The electrostatic chuck 65 is heated, thereby heating the substrate W attracted to the electrostatic chuck 65.

[0033] The temperature sensor 64 is connected to a temperature converter 73. The temperature converter 73 converts a signal from the temperature sensor 64 into a temperature signal, and outputs the signal to the control unit 4.

[0034] The heating driver 71 supplies power to the heating unit 63 so as to bring the temperature of the mounting table 60 to a set target value. Specifically, the heating driver 71 adjusts the power supplied to the heating unit 63 based on a control signal from the control unit 4. The heating driver 71 adjusts the power supplied to the heating unit 63 so that the temperature of the mounting table 60 is constant at the target value.

[0035] The control unit 4 controls the heating drive unit 71 based on the temperature output from the temperature converter 73. Specifically, the control unit 4 controls the heating drive unit 71 so that the temperature of the mounting table 60 becomes a set temperature (set temperature, target value). That is, the control unit 4 controls the power supplied from the heating drive unit 71 to the heating unit 63 so that the temperature detected by the temperature sensor 64 becomes the set temperature (target value). For example, the control unit 4 controls the heating drive unit 71 by PID (Proportional-Integral-Differential) control.

[0036] <Method for detecting abnormality in substrate processing apparatus 5> A description will now be given of an abnormality detection method performed by the control unit 4. Fig. 4 is a flow chart showing an example of an abnormality detection method for the substrate processing apparatus 5, which is an example of the substrate processing apparatus of the semiconductor manufacturing apparatus according to this embodiment.

[0037] First, the substrate W is placed on the electrostatic chuck 65 of the mounting table 60 by any one of the transfer modules TM1, TM2, TM3, TM4, and TM5.

[0038] It is assumed that the substrate W is not electrostatically attracted by the electrostatic chuck 65 before the control unit 4 starts the abnormality detection method.

[0039] The control unit 4 measures the initial power supplied to the heating unit 63 (step S10) before the electrostatic chuck 65 attracts the substrate W. The initial power is the power supplied from the heating drive unit 71 to heat the mounting table 60 to a predetermined temperature.

[0040] The temperature of the mounting table 60 is controlled to be, for example, a set temperature (target value) of the substrate W in the substrate processing. For example, when the set temperature (target value) of the substrate W in the substrate processing is 350° C., the control unit 4 controls the heating drive unit 71 so that the temperature of the mounting table 60 becomes 350° C. before the electrostatic chuck 65 adsorbs the substrate W.

[0041] Note that when measuring the initial power, a moving average of the power before a set time before the electrostatic chuck 65 attracts the substrate W may be measured, or the average of the power during a predetermined period before the set time before the electrostatic chuck 65 attracts the substrate W. Note that the set time may be determined, for example, by evaluation using an actual device.

[0042] After the measurement of the initial power is completed, the control unit 4 controls the DC power supply 72 to start suction of the substrate W (step S20).

[0043] The control unit 4 starts measuring the time change of the power supplied from the heating drive unit 71 to the heating unit 63 at the same time as starting the suction of the substrate W (step S30).

[0044] Before the substrate processing, the temperature of the substrate W is approximately equal to the temperature of the transfer chamber 12. The temperature of the transfer chamber 12 is approximately room temperature (approximately 20° C.). Therefore, the temperature of the substrate W is lower than the temperature of the mounting table 60.

[0045] When the electrostatic chuck 65 attracts the substrate W, heat is transferred from the electrostatic chuck 65 to the substrate W. The transfer of heat from the electrostatic chuck 65 to the substrate W reduces the temperature of the electrostatic chuck 65. When the temperature of the electrostatic chuck 65 reduces, the temperature of the base portion 62 also reduces. Since the control unit 4 controls the temperature of the mounting table 60 to be constant, when the temperature of the base portion 62 reduces, the power supplied to the heating unit 63 by the heating drive unit 71 is increased in order to raise the temperature of the mounting table 60.

[0046] Next, an abnormality in the attraction in the electrostatic chuck 65 is determined based on the change over time of the power supplied to the heating unit 63 measured in step S30 (step S40).

[0047] Step S40 is an example of a process for detecting an abnormality in the adsorption of the substrate W by the electrostatic chuck 65.

[0048] The coefficient of heat transfer between the substrate W and the electrostatic chuck 65 differs depending on the force of attraction of the electrostatic chuck 65 to attract the substrate W. For example, when the force of attraction of the electrostatic chuck 65 to attract the substrate W is strong, the coefficient of heat transfer between the substrate W and the electrostatic chuck 65 is high. On the other hand, when the force of attraction of the electrostatic chuck 65 to attract the substrate W is weak, the coefficient of heat transfer between the substrate W and the electrostatic chuck 65 is low.

[0049] Therefore, when the electrostatic chuck 65 strongly attracts the substrate W, more heat is transferred from the electrostatic chuck 65 to the substrate W, causing a large change in temperature of the electrostatic chuck 65. In response to the change in temperature of the electrostatic chuck 65, the power supplied from the heating driver 71 to the heating unit 63 also changes greatly.

[0050] On the other hand, when the electrostatic chuck 65 weakly adsorbs the substrate W, the heat transferred from the electrostatic chuck 65 to the substrate W is less than when the electrostatic chuck 65 strongly adsorbs the substrate W. Therefore, the change in temperature of the electrostatic chuck 65 is smaller than when the electrostatic chuck 65 strongly adsorbs the substrate W. And, the change in power supplied from the heating driver 71 to the heating unit 63 in response to the change in temperature of the electrostatic chuck 65 is smaller than when the electrostatic chuck 65 strongly adsorbs the substrate W.

[0051] Therefore, an abnormality in the adsorption of the electrostatic chuck 65 can be detected based on the fluctuation in the power supplied by the heating driver 71 caused by the adsorption of the substrate W by the electrostatic chuck 65. For example, the control unit 4 determines that there is an abnormality when the fluctuation in the power supplied by the heating driver 71 when the electrostatic chuck 65 adsorbs the substrate W is small. Then, it is possible to monitor whether the substrate W is being adsorbed by the electrostatic chuck 65 with a sufficient adsorption force.

[0052] <Evaluation index for power fluctuation> A method for calculating an evaluation index for the fluctuation in power supplied by the heating driver 71 caused by the attraction of the substrate W by the electrostatic chuck 65 will be described.

[0053] [Differential integration method] In order to calculate the fluctuation in the power supplied by the heating driver 71, the control unit 4 integrates the fluctuation in the power with respect to a certain reference value (reference power value Wi) to calculate the evaluation index. Figures 5 and 6 are diagrams for explaining the differential integration method of the abnormality detection method for the substrate processing apparatus 5 of the semiconductor manufacturing apparatus according to this embodiment.

[0054] In the difference integral method, the integral value of the absolute value of the difference is calculated with respect to a certain reference value during the processing step.

[0055] 5 and 6, a step for placing the substrate W is performed before the time reaches 5 seconds. For example, the substrate W is placed on pins provided on the mounting table 60 by any one of the transfer modules TM1, TM2, TM3, TM4, and TM5. Then, the pins are stored inside the mounting table 60. By storing the pins inside the mounting table 60, the substrate W is placed on the mounting table 60.

[0056] During the step for placing the substrate W, the power (reference power) supplied to the heating unit 63 is measured. The reference power is, for example, the initial power in step S10. For example, the line Linit in Fig. 5 represents the reference power value Wi. Fig. 6 represents the absolute value (amplitude) of the difference between the measured power and the reference power value Wi.

[0057] Then, at time 5 seconds, the electrostatic chuck 65 starts to attract the substrate W. When the electrostatic chuck 65 attracts the substrate W, heat is transferred from the electrostatic chuck 65 to the substrate W, and the temperature of the mounting table 60 including the electrostatic chuck 65 decreases. Then, to compensate for the decrease in temperature of the mounting table 60, the power supplied from the heating driver 71 to the heating unit 63 increases.

[0058] Then, the substrate is processed for 30 seconds between 10 seconds and 40 seconds (the period of Step in FIG. 5). The substrate is processed, for example, by stacking a material on the substrate W.

[0059] The absolute value of the difference from the reference power in the process is integrated. The process start time is t1 (=10) seconds, the end time is t2 (=40) seconds, and the power value measured at time t is P(t). The difference integral value WS is calculated using Equation 1.

[0060]

number

[0061] Specifically, the sum of the areas A1, A2, A3, and A4 in FIG. 5 and FIG. 6 is calculated.

[0062] Then, the controller 4 compares the obtained difference integral value WS with the set threshold value Wth in the step. If the obtained difference integral value WS is smaller than the set threshold value Wth, it is determined that the electrostatic chuck 65 is not sufficiently attracted to the substrate W. In other words, the controller 4 determines that there is an abnormality in the attraction of the substrate W by the electrostatic chuck 65.

[0063] In addition, when calculating the difference integral value WS, in the case of a substrate process including a plurality of steps, the absolute value of the difference from the reference power from the first step may be accumulated for each step, and the difference integral value WS may be calculated from the difference from the previous step for the accumulated value.

[0064] 7 is a diagram showing the power supplied to the heating unit 63 and the temperature change of the substrate W when the voltage supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65 is changed. The line LpowerH represents the power supplied from the heating driver 71 to the heating unit 63 when a voltage of 350 volts is supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65.

[0065] A line LpowerL represents the power supplied from the heating drive unit 71 to the heating unit 63 when a voltage of 175 volts is supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65. A line LtempH represents the temperature of the substrate W when a voltage of 350 volts is supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65. A line LtempL represents the temperature of the substrate W when a voltage of 175 volts is supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65.

[0066] The temperature of the substrate W was measured by attaching a thermocouple to the surface of the substrate W.

[0067] 7, the fluctuation in the power supplied from the heating driver 71 was larger when a voltage of 350 volts was supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65 than when a voltage of 175 volts was supplied to the electrode 66 of the electrostatic chuck 65. In other words, the fluctuation in the power supplied from the heating driver 71 was larger when the adsorptive force of the electrostatic chuck 65 was strong than when the adsorptive force of the electrostatic chuck 65 was weak.

[0068] 7, the temperature of the substrate W changed more quickly when a voltage of 350 volts was supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65 than when a voltage of 175 volts was supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65. That is, the temperature of the substrate W changed more quickly when the adsorptive force of the electrostatic chuck 65 was strong than when the adsorptive force of the electrostatic chuck 65 was weak.

[0069] 8 is a diagram showing the temperature changes of the mounting table 60 and the substrate W when the voltage supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65 is changed. The line LtempSH represents the temperature of the mounting table 60 when a voltage of 350 volts is supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65. The line LtempSL represents the temperature of the mounting table 60 when a voltage of 175 volts is supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65. The temperature of the substrate W is the same as that in FIG.

[0070] 8, the temperature change of the mounting table 60 was larger when a voltage of 350 volts was supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65 than when a voltage of 175 volts was supplied from the DC power supply 72 to the electrode 66 of the electrostatic chuck 65. That is, the temperature change of the mounting table 60 was larger when the attracting force of the electrostatic chuck 65 was strong than when the attracting force of the electrostatic chuck 65 was weak.

[0071] From the above results, it is possible to detect an abnormality in the adsorptive force of the electrostatic chuck 65 by measuring the power supplied to the heating unit 63. It is also possible to monitor whether the substrate W is being adsorptively attracted by the electrostatic chuck 65 with a sufficient adsorptive force.

[0072] The control unit 4 is an example of a detection unit.

[0073] Next, a result of performing the substrate processing several times with the suction force reduced will be described. Fig. 9 is a diagram for explaining the result of performing the abnormality detection method for the substrate processing apparatus 5 which is the substrate processing apparatus of the semiconductor manufacturing apparatus according to this embodiment.

[0074] Here, the voltage supplied to the electrostatic chuck 65 in a normal processing cycle is set to 350 volts. Then, in the 5th, 13th, 21st, and 29th processing cycles, the voltage supplied to the electrostatic chuck 65 is set to 175 volts, and anomaly determination is performed.

[0075] As a result, as shown in Fig. 9, the difference integral value became small in the 5th, 13th, 21st, and 29th processing cycles. Then, for example, by setting the set threshold value Wth to 67%, it is possible to correctly detect an abnormality. In addition, it is possible to monitor whether the substrate W is attracted by the electrostatic chuck 65 with a sufficient attracting force.

[0076] <<Second embodiment>> <Evaluation index for power fluctuation (part 2)> A second embodiment having a different evaluation index for the power fluctuation from that of the first embodiment will be described. A second method for calculating an evaluation index for the power fluctuation supplied by the heating driver 71 caused by the electrostatic chuck 65 attracting the substrate W will be described.

[0077] [Simple integration method] 10, the fluctuation is evaluated using a simple integral value WD obtained by integrating the power supplied to the heating unit 63 in a processing step Step. The simple integral value WD is calculated based on Equation 2, where the processing start time is t1 (=10) seconds, the end time is t2 (=40) seconds, and the power value measured at time t is P(t).

[0078]

number

[0079] Specifically, the area A10 in FIG. 10 is calculated.

[0080] Even if the simple integral value WD obtained by the simple integration method is used as an evaluation index, it is possible to monitor whether the substrate W is attracted by the electrostatic chuck 65 with a sufficient attracting force.

[0081] The evaluation index of the power fluctuation is not limited to the above-mentioned differential integral value WS or simple integral value WD. For example, the peak value, maximum value, or maximal value of the power fluctuation may be used.

[0082] <<Third embodiment>> A method for evaluating the performance of an evaluation index for the fluctuation in power supplied by the heating driver 71 caused by the attraction of the substrate W by the electrostatic chuck 65 will be described.

[0083] FIG. 11 shows the distribution of the evaluation indexes when a plurality of processing cycles including the case where the adsorption force is small in the electrostatic chuck 65 as shown in FIG.

[0084] The distribution Dist1 is a distribution of evaluation indexes calculated multiple times when a voltage is supplied to the electrode 66 of the electrostatic chuck 65 so that a sufficient adsorption force is generated in the electrostatic chuck 65 (for example, when a voltage of 350 volts is supplied to the electrode 66 of the electrostatic chuck 65).

[0085] The distribution Dist2 is a distribution of evaluation indexes calculated multiple times when half the voltage at which a sufficient adsorption force is generated in the electrostatic chuck 65 is supplied (for example, when a voltage of 175 volts is supplied to the electrode 66 of the electrostatic chuck 65).

[0086] The standard deviation σ is the standard deviation of the distribution Dist1, and the mean difference D is the difference between the mean of the distribution Dist1 and the mean of the distribution Dist2.

[0087] The value obtained by dividing the average difference D by the standard deviation σ is called the performance evaluation value R. The performance of the evaluation index is evaluated based on this performance evaluation value.

[0088] <Comparison of evaluation indicators> When the differential integral value WS was used, the performance evaluation value R1 was 8.2. On the other hand, when the simple integral value WD was used, the performance evaluation value R2 was 7.1. Therefore, the performance evaluation value is larger when the differential integral value WS is used. Therefore, it is more preferable to use the differential integral value WS as the evaluation index.

[0089] The performance evaluation value may be used to determine the performance evaluation value in a plurality of processes, and an abnormality in the electrostatic chuck may be detected using an evaluation index with a high performance evaluation value in each process.

[0090] Note that 350 volts is an example of a first voltage value, and 175 volts is an example of a second voltage value. The distribution Dist1 is an example of a first distribution, and the distribution Dist2 is an example of a second distribution.

[0091] The present embodiment disclosed herein should be considered as illustrative and not restrictive in all respects. The above-described embodiment can be modified and improved in various forms without departing from the scope and spirit of the appended claims. The matters described in the above-described embodiments can be configured in other ways without contradiction, and can be combined without contradiction. [Explanation of symbols]

[0092] 1. Semiconductor manufacturing equipment 5. Substrate Processing Equipment 50 Processing vessel 60 Placement table 62 Base 63 Heating section 64 Temperature Sensor 65 Electrostatic Chuck 66 electrodes 67 Dielectric Film 71 Heating drive unit 72 DC power supply 73 Temperature Converter

Claims

1. a mounting table including an electrostatic chuck for attracting a substrate; A heating unit that heats the mounting table; a heating driving unit that supplies power to the heating unit so as to set the temperature of the mounting table to a target value; a detection unit that detects an abnormality in the attraction of the substrate by the electrostatic chuck; Equipped with the detection unit detects the abnormality based on a fluctuation in the power supplied to the heating unit caused by attraction of the substrate by the electrostatic chuck; The detection unit calculates an evaluation index for evaluating the variation, the detection unit applies a voltage of a first voltage value to the electrostatic chuck, the electrostatic chuck attracts the substrate, and calculates the evaluation index a plurality of times to calculate a first distribution; applies a voltage of a second voltage value smaller than the first voltage value to the electrostatic chuck, the electrostatic chuck attracts the substrate, and calculates the evaluation index a plurality of times to calculate a second distribution; and calculates a performance evaluation value based on the first distribution and the second distribution. Substrate processing equipment.

2. The performance evaluation value is a value obtained by dividing the difference between the mean of the first distribution and the mean of the second distribution by the standard deviation of the first distribution. The substrate processing apparatus according to claim 1 .

3. 1. A method for detecting an abnormality in a substrate processing apparatus, the method comprising: a mounting table having an electrostatic chuck for attracting a substrate; a heating unit for heating the mounting table; and a heating driver for supplying power to the heating unit so as to adjust a temperature of the mounting table to a target value, the method comprising: detecting an abnormality in the electrostatic chuck attracting the substrate based on a fluctuation in the power supplied to the heating unit, the fluctuation being caused by the electrostatic chuck attracting the substrate; In the step of detecting an abnormality, Calculating an evaluation index for evaluating the variation; applying a voltage having a first voltage value to the electrostatic chuck to attract the substrate to the electrostatic chuck, and calculating the evaluation index a plurality of times to calculate a first distribution; applying a voltage of a second voltage value smaller than the first voltage value to the electrostatic chuck to attract the substrate to the electrostatic chuck, and calculating the evaluation index a plurality of times to calculate a second distribution; calculating a performance evaluation value based on the first distribution and the second distribution; A method for detecting an abnormality in a substrate processing apparatus.

4. the performance evaluation value is a value obtained by dividing a difference between an average of the first distribution and an average of the second distribution by a standard deviation of the first distribution. The method for detecting an abnormality in a substrate processing apparatus according to claim 3 .

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