Calibration method and calibration system

Abstract

To provide reducing a difference in emission spectrochemical analysis between machines.SOLUTION: There is provided a calibration method including the steps of: arranging an LED light source having a given wavelength range in a reference device; changing the quantity of light output from the arranged LED light source to acquire first data that is a light emission intensity for every wavelength in the gradually adjusted light quantity; storing the first data in a memory; arranging the LED light source in a device to be calibrated; changing the quantity of light output from the arranged LED light source to acquire second data that is a light emission intensity for every wavelength in the gradually adjusted light quantity; and calculating a calibration formula based on the first data stored in the memory and the second data.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] Patent Document 1 discloses a plasma processing apparatus in which an optical emission spectrometer is connected to a plasma process chamber and the process is monitored and controlled by analyzing the spectral intensity of the plasma emission generated in the chamber. Patent Document 2 discloses a system in which an optical calibration device equipped with a light source having a continuous spectrum such as a xenon flash lamp is installed in the chamber to calibrate the optical emission spectrometer. [Prior art documents] [Patent documents]

[0002] [Patent Document 1] Special Publication No. 2011-517097 [Patent Document 2] JP 2018-91836 A Summary of the Invention [Problem to be solved by the invention]

[0003] The present disclosure provides a technique for reducing the instrumental error in optical emission spectroscopy. [Means for solving the problem]

[0004] According to one aspect of the present disclosure, there is provided a calibration method including the steps of: arranging an LED light source having a given wavelength band in a reference device; varying the amount of light output from the arranged LED light source to obtain first data which is the emission intensity for each wavelength at the gradually adjusted amount of light; storing the first data in a memory; arranging the LED light source in a device to be calibrated; varying the amount of light output from the arranged LED light source to obtain second data which is the emission intensity for each wavelength at the gradually adjusted amount of light; and calculating a calibration formula based on the first data and the second data stored in the memory. Effect of the Invention

[0005] According to one aspect, it is possible to reduce the instrumental error in optical emission spectrometry. [Brief description of the drawings]

[0006] [Figure 1] 1 is a schematic cross-sectional view showing a plasma processing apparatus according to an embodiment; [Diagram 2] FIG. 1 is a diagram showing an overview of calibration according to an embodiment. [Diagram 3] A diagram of the plasma processing device in Figure 1 with an LED jig attached. [Figure 4] 3 is a diagram for explaining the operation between the plasma processing apparatus and the optical emission spectrometer according to the embodiment; FIG. [Diagram 5] FIG. 4 is a diagram showing an example of reference calibration data according to the embodiment. [Figure 6] 4 is a flowchart showing a calibration method (acquisition of reference calibration data) according to the embodiment. [Figure 7] 4 is a flowchart showing a calibration method (calculation of a calibration equation) according to the embodiment. [Figure 8] 4 is a flowchart showing a calibration method (calibration of detection values) according to the embodiment. [Figure 9] FIG. 11 is a diagram showing an example of a calibration result according to the embodiment. [Figure 10] FIG. 13 is a diagram showing an example of an LED jig according to a modified example of the embodiment. [Figure 11] 10A to 10C are diagrams for explaining the operation of a semiconductor manufacturing apparatus according to a modified example of the embodiment. [Figure 12] 10A to 10C are diagrams for explaining an LED light source according to a modified example of the embodiment. [Figure 13] FIG. 13 is a perspective view showing an LED light source according to a modified example of the embodiment. [Figure 14] Cross section AA of Figure 13. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and duplicated descriptions may be omitted.

[0008] [Plasma processing equipment] A plasma processing apparatus 10 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic cross-sectional view showing an example of the plasma processing apparatus 10 according to an embodiment.

[0009] The plasma processing apparatus 10 performs substrate processing such as etching processing and film formation processing. The plasma processing apparatus 10 shown in FIG. 1 is a capacitively coupled plasma (CCP) processing apparatus, and plasma is generated between an upper electrode 3 and a mounting table ST in a chamber 2. The mounting table ST has a lower electrode 4 and an electrostatic chuck 5. During processing, a substrate W is held on the electrostatic chuck 5. A first high frequency power supply 6 is connected to the upper electrode 3, and a second high frequency power supply 7 is connected to the lower electrode 4. In another example, the first high frequency power supply 6 and the second high frequency power supply 7 may be connected to the lower electrode 4. The first high frequency power supply 6 outputs a first high frequency power, and the second high frequency power supply 7 outputs a second high frequency power. The frequency of the second high frequency power is lower than the frequency of the first high frequency power. For example, the frequency of the first high frequency power supply 6 may be 40 MHz to 100 MHz, and the frequency of the second high frequency power supply may be 200 kHz to 40 MHz. A gas supply unit 8 is connected to the chamber 2 to supply a processing gas. Further, an exhaust device 9 is connected to the chamber 2 to exhaust the inside of the chamber 2 .

[0010] An observation window 101 is provided on the side wall of the chamber 2. The observation window 101 is made of, for example, quartz, and is configured to transmit light while maintaining a vacuum state in the chamber 2. An optical emission spectrometer 100 is connected to the observation window 101 via a focusing component 107 such as a mirror or lens and an optical fiber 102. The optical emission spectrometer 100 detects the emission spectrum of the plasma, determines the state of the plasma from the emission spectrum, and monitors and controls the process executed in the plasma processing apparatus 10. An example of the optical emission spectroscopy (OES) of the optical emission spectrometer 100 is EPD (End Point Detection). This allows the state of the plasma to be monitored, and the etching process and cleaning process to be monitored.

[0011] The plasma processing apparatus 10 has a control unit 180. The control unit 180 may be a computer including a processor, a storage unit such as a memory, an input device, a display device, a signal input / output interface, and the like. The control unit 180 controls each unit of the plasma processing apparatus 10. In the control unit 180, an operator can use the input device to input commands and the like to manage the plasma processing apparatus 10. In addition, the control unit 180 can visualize and display the operating status of the plasma processing apparatus 10 using the display device. Furthermore, the storage unit stores a control program and recipe data. The control program is executed by the processor to execute various processes in the plasma processing apparatus 10. The processor executes the control program and controls each unit of the plasma processing apparatus 10 according to the recipe data.

[0012] The optical emission spectrometer 100 is calibrated independently against an arbitrary standard before being shipped from a spectroscopic sensor manufacturer. However, the emission of plasma is monitored by the optical emission spectrometer 100 connected via attachment parts such as an observation window 101, a mirror or lens light collecting part 107, and an optical fiber 102. Therefore, even if the optical emission spectrometer 100 is calibrated independently against an arbitrary standard, when the optical emission spectrometer 100 is connected to the chamber 2, it may be affected by the attachment parts, etc., and an error may occur in the detection result of the optical emission spectrometer 100 for each chamber. This may cause errors to accumulate in the log data of the monitoring record of the optical emission spectroscopic analysis, affecting data analysis and reducing productivity.

[0013] Therefore, in the calibration method according to this embodiment, an LED jig 20 equipped with an LED (light emitting diode) light source 21 serving as a reference for calibration (described later) is installed in a reference device (see FIG. 3), and light is irradiated onto an optical emission spectrometer 100 connected to a chamber 2.

[0014] The irradiated reference light is broad light, and has a function capable of adjusting the output of the LED light by CPU 104 of optical emission spectrometer 100, which will be described later. The irradiated light is incident on optical emission spectrometer 100 via various attachment parts, such as the structure in chamber 2, observation window 101, light collecting part 107, optical fiber 102, etc. Since the irradiated reference light is calibrated and constant, any difference from the data that should have been obtained is due to the influence of the attachment parts in chamber 2. Therefore, by calibrating these differences for each chamber, it is possible to reduce the instrumental difference in optical emission spectroscopic analysis using optical emission spectrometer 100.

[0015] [Proofreading Overview] 2, a reference plasma processing apparatus 10c (hereinafter referred to as reference apparatus 10c) is installed in a factory C of a semiconductor manufacturing equipment manufacturer. An LED jig 20 is installed in a chamber of the reference apparatus 10c to which an optical emission spectrometer 100 calibrated in a factory D of a spectroscopic sensor manufacturer is attached, and reference calibration data is obtained.

[0016] In a semiconductor manufacturing equipment manufacturer's factory E (factories C and E may be the same factory), a plasma processing apparatus 10e to be calibrated (hereinafter referred to as calibration target apparatus 10e) to be shipped to a semiconductor manufacturer's factory F is disposed. An optical emission spectrometer 100 calibrated in a spectroscopic sensor manufacturer's factory D is attached to the calibration target apparatus 10e. After the calibration target apparatus 10e is shipped to the factory F, an LED jig 20 is installed in the chamber of the calibration target apparatus 10e, and calibration (initial calibration) is performed (FIG. 2(1)). When performing calibration (initial calibration), a calibration formula is calculated with reference to the reference calibration data. Calibration (initial calibration) may be performed on the calibration target apparatus 10e while it is in factory E before being shipped to factory F (FIG. 2(2)).

[0017] It is preferable that the calibration is performed periodically while the calibration target apparatus 10e is in operation. The periodic calibration performed in the factory F may be performed during maintenance of the calibration target apparatus 10e. During substrate processing, reaction products adhere to the observation window 101, causing the observation window 101 to gradually become cloudy. Therefore, it is preferable to perform calibration after removing the reaction products by cleaning during maintenance of the plasma processing apparatus 10.

[0018] FIG. 3 is an example of a schematic cross-sectional view of an LED jig 20 attached in a chamber of the plasma processing apparatus 10 of FIG. 1. The plasma processing apparatus 10 includes a reference apparatus 10c and a calibration target apparatus 10e. As shown in FIG. 3, the LED jig 20 has an LED light source 21 and a support portion 23 for supporting the LED light source 21, and the support portion 23 is bridged across the wall of the chamber 2 and installed in the chamber 2. As a result, the LED light source 21 is arranged facing the observation window 101 at a position approximately horizontal to the observation window 101. The LED jig 20 is arranged with the lid on the top of the chamber 2 open. The LED jig 20 may have a communication unit and a control unit. The LED jig 20 installed in the chamber of the reference apparatus 10c and the LED jig 20 installed in the chamber of the calibration target apparatus 10e are the same jig.

[0019] [Operation between the plasma processing device and the optical emission spectrometer] Next, a brief description will be given of the operation between the plasma processing apparatus 10 (reference apparatus 10c, calibration target apparatus 10e) and the optical emission spectrometer 100. Fig. 4 is a diagram for explaining the operation between the plasma processing apparatus 10 and the optical emission spectrometer 100 according to the embodiment.

[0020] The optical emission spectrometer 100 includes a detection unit 103, a CPU 104, and a memory 105. The memory 105 stores a given program for analyzing the emission intensity of the LED light and the emission intensity of the plasma detected by the optical emission spectrometer 100.

[0021] The CPU 104 switches the operation contents between a calibration mode and a detection mode. In the calibration mode, the CPU 104 executes a given calibration program stored in the memory 105 to instruct the LED light source 21 to turn on / off. The CPU 104 causes the detection unit 103 to detect the light output from the LED light source 21 in the plasma processing apparatus 10 as the reference apparatus 10c or the calibration target apparatus 10e. The detection unit 103 detects the emission intensity of the LED light, the amount of which is adjusted stepwise, output from the LED light source 21 mounted on the LED jig 20. The data detected by the reference apparatus 10c is called "first data", and the first data is stored in the memory 105 as reference calibration data. The reference calibration data is reference information for calibration. The data detected by the calibration target apparatus 10e is called "second data".

[0022] 5(a) shows the detection result of the optical emission spectrometer 100 detecting the light output from the LED light source 21 when the CPU 104 controls the current value supplied to the LED light source 21 from 50 mA to 350 mA in increments of 50 mA. The horizontal axis of FIG. 5(a) represents the wavelength of light, and the vertical axis represents the emission intensity of the LED light at each wavelength for each current value detected by the optical emission spectrometer 100. According to this, as the current value increases, the emission intensity of the LED light output from the LED light source 21 increases. In other words, the CPU 104 can output LED light with the light amount adjusted in stages from the LED light source 21 by controlling the current value supplied to the LED light source 21.

[0023] FIG. 5(b) shows an example of the emission intensity of the LED light detected by the optical emission spectrometer 100 when the LED light source 21 is controlled at current values ​​of 50 mA, 100 mA, 150 mA, 200 mA, 250 mA, 300 mA, and 350 mA at the wavelength of 449 nm in FIG. 5(a). The horizontal axis of FIG. 5(b) shows the first data, and the vertical axis shows the second data. That is, FIG. 5(b) is a graph showing the correlation between the first data and the second data. Note that the first data and the second data are not limited to the wavelengths mentioned above, and may be emission intensities for the stepwise adjusted light amounts for LED light of a specific wavelength in the wavelength band of 200 nm to 870 nm.

[0024] In Fig. 5(b), when the second data detected from the optical emission spectrometer 100 connected to the calibration target device 10e matches the first data, which is the reference calibration data, the correlation is represented by y = x. However, in reality, the second data differs from the first data due to the influence of attached parts and the like, and differences occur due to machine differences between chambers. Therefore, an approximation equation showing the correlation between the first data and the second data is represented by y = Ax + B.

[0025] [Calibration method (obtaining reference calibration data)] Next, an operation for acquiring reference calibration data in the calibration method according to the embodiment will be described with reference to Fig. 6. Fig. 6 is a flowchart showing the calibration method (acquisition of reference calibration data) according to the embodiment. Note that, before this process is started, as shown in the dotted line frame in Fig. 6, the chamber 2 of the reference device 10c is opened, the LED jig 20 is installed in the chamber 2, and the reference LED light source 21 is placed in the chamber 2 so that it can project light onto the observation window 101.

[0026] When this process is started, the CPU 104 of the optical emission spectrometer 100 attached to the reference device 10c switches from detection mode to calibration mode (step S21). Next, the CPU 104 transmits an instruction signal to turn on the LED, and transmits a control signal to indicate the current value (step S1). It is also possible to transmit only an instruction signal to turn on the LED, or only a control signal to indicate the current value.

[0027] In response to this, the communication unit of the LED jig 20 receives the instruction signal to turn on the LED and the control signal instructing the current value. The control unit of the LED jig 20 turns on the LED light source 21 in response to the received instruction signal (step S11).

[0028] Next, the control unit determines whether a control signal instructing a current value has been received (step S12). If the control unit determines that a control signal instructing a current value has been received, the result is Yes, and the control unit controls (changes) the value of the current supplied to the LED light source 21 based on the control signal instructing the current value (step S13). As a result, LED light of an amount of light corresponding to the current value supplied to the LED light source 21 is output. The detection unit 103 of the optical emission spectrometer 100 detects the emission intensity of the output amount of LED light, and the CPU 104 acquires the detected emission intensity, i.e., first data (reference calibration data) (step S2).

[0029] In step S12, if the control unit of the LED jig 20 determines that it has not received a control signal instructing a current value, it determines whether a predetermined time has elapsed (step S14) and waits until the predetermined time has elapsed. If the control signal is received before the predetermined time has elapsed, the process proceeds to step S13, and the current value supplied to the LED light source 21 is changed based on the control signal. If the predetermined time has elapsed before receiving the control signal in step S14, the control unit turns off the LED light source 21 (step S15). As a result, the LED jig 20 is removed from the chamber 2 (step S16), and this process ends.

[0030] Meanwhile, in the optical emission spectrometer 100, in step S1, every time a control signal instructing a current value is sent from the CPU 104, LED light whose light amount is adjusted stepwise is output from the LED light source 21 in accordance with the current value changed by the processes of steps S11 to S13. The detector 103 detects the emission intensity of the LED light whose light amount is adjusted stepwise, obtains first data (reference calibration data) (step S2), and stores it in the memory 105 (step S3). Then, this process ends.

[0031] By executing this process for each wavelength, first data corresponding to each wavelength from 200 nm to 870 nm can be obtained.

[0032] [Calibration method (calculation of calibration formula)] Next, an operation for calculating a calibration equation in the calibration method according to the embodiment will be described with reference to Fig. 7. Fig. 7 is a flowchart showing the calibration method (calculation of the calibration equation) according to the embodiment.

[0033] Before this process is started, the chamber 2 of the calibration target device 10e is opened, the LED jig 20 is installed in the chamber 2, and the reference LED light source 21 is placed in the chamber 2, as shown in the dotted line frame in Fig. 7. In the following, the same step numbers are used for steps that perform the same processes as the steps in Fig. 6. Explanations of steps with the same step numbers are omitted as much as possible.

[0034] When this process is started, the CPU 104 of the optical emission spectrometer 100 attached to the calibration target device 10e switches from the detection mode to the calibration mode (step S21). The CPU 104 also reads the first data stored in the memory 105 of the optical emission spectrometer 100 connected to the reference device 10c (step S22).

[0035] Next, the CPU 104 transmits an instruction signal to turn on the LED, and transmits a control signal to instruct the current value (step S1). The LED fixture 20 executes the processes of steps S11 to S16. Meanwhile, the detection unit 103 of the optical emission spectrometer 100 detects the emission intensity of the LED light output from the LED light source 21, the amount of light of which has been adjusted in stages, and acquires second data (step S23). Next, the second data is compared with the first data (step S24), and an approximation equation y=Ax+B is calculated using the first data and the second data (step S25).

[0036] Next, the CPU 104 calculates the coefficient of determination R 2 (Step S4) The coefficient of determination R 2 is equal to or greater than a given threshold, it can be determined that the approximation formula (see FIG. 5(b)) showing the correlation between the first data and the second data has linearity.

[0037] Next, when CPU 104 determines in step S5 that the approximation formula showing the correlation between the first data and the second data has linearity, it calculates a calibration formula x=(1 / A)yB / A from the approximation formula y=Ax+B (step S26). CPU 104 stores the calibration formula x=(1 / A)yB / A in memory 105 (step S27) and ends this process.

[0038] If it is determined in step S5 that the approximation formula showing the correlation between the first data and the second data does not have linearity, then CPU 104 outputs an error (step S6) and ends this process.

[0039] [Calibration method (calibration of detection value)] Next, an operation of calibrating the detection value of the optical emission spectrometer 100 in the calibration method according to the embodiment will be described with reference to Fig. 8 and Fig. 9. Fig. 8 is a flowchart showing the calibration method (calibration of the detection value) according to the embodiment. Fig. 9 is a diagram showing an example of the calibration result according to the embodiment.

[0040] When this process is started, the CPU 104 of the optical emission spectrometer 100 attached to the calibration target device 10e switches from the calibration mode to the detection mode (step S31). Next, the CPU 104 reads the calibration equation x=(1 / A)yB / A stored in the memory 105 (step S32). Next, the detection unit 103 detects the optical emission intensity of a specific wavelength of the plasma generated in the chamber 2 of the calibration target device 10e, and the CPU 104 acquires the detected optical emission intensity (step S33). Next, the CPU 104 calibrates the acquired optical emission intensity based on the calibration equation x=(1 / A)yB / A of the specific wavelength that is the same as the wavelength of the detected optical emission intensity (step S34), acquires third data, and ends this process.

[0041] As a result, the emission intensity, which is the detection value of the emission spectrometer 100 on the approximation formula shown in Fig. 5(b), can be calibrated to the emission intensity on y = x shown in Fig. 5(b) using the calibration formula of x = (1 / A) yB / A. This makes it possible to eliminate deviations in the detection value of the emission spectrometer 100 caused by the influence of mounting parts for each chamber, etc.

[0042] In the above description, the CPU 104 controls each step of the calibration process for obtaining the reference calibration data, calculating the calibration equation, and calibrating the detection value. However, this is not limited to the above, and the control unit 180 of the plasma processing device 10 may control each step of the calibration.

[0043] Also, although the CPU 104 has been described as transmitting an instruction signal to turn on the LED and a control signal to indicate a current value (step S1), this is not limiting, and the LED may be locally controlled to control the on / off and current value of the LED. For example, an instruction signal to turn on / off the LED and a control signal to control the current value to be passed through the LED may be transmitted from an electronic device (not shown) that is different from the CPU 104 and can communicate with the LED jig 20.

[0044] As described above, according to the calibration method of this embodiment, for example, the plasma processing apparatus 10 of a mass production device is treated as the calibration target device, and the deviation of the detection value of the optical emission spectrometer 100 attached to the plasma processing apparatus 10 is identified and calibrated. This makes it possible to output the same detection value regardless of which optical emission spectrometer 100 is used.

[0045] For example, as shown in Fig. 9, there is a discrepancy between the emission intensity (first data) of plasma detected in the chamber of the reference device 10c and the emission intensity (second data) of plasma detected in, for example, chambers A and B of the calibration target device 10e. This discrepancy in the detection value of the optical emission spectrometer 100 is calibrated by the calibration method according to the present embodiment. As a result, the detection values ​​detected by the optical emission spectrometers 100 attached to the multiple chambers A and B are made to match the first data as shown by the arrows in Fig. 9. This makes it possible to prevent discrepancies from occurring with the detection values ​​detected by the optical emission spectrometers 100 attached to the chambers of the reference device 10c.

[0046] This makes it possible to reduce errors in the log data of the monitoring records of the optical emission spectroscopic analysis occurring in a plurality of chambers, to increase the accuracy of the data analysis of the spectroscopic analysis, and to improve productivity.

[0047] [LED fixture] In the calibration method described above, the LED jig 20 is equipped with an LED light source 21, and the LED light source 21 is used as a standardized reference light source. LED light sources include OLEDs (organic light emitting diodes). While the amount of light emitted by a lamp light source decreases over time, the use of an LED or an OLED in the calibration method according to the embodiment can prevent the amount of light from decreasing over time. Furthermore, the LED light source 21 has smaller individual differences than a lamp light source, and is a stable light source over a long period of time. Therefore, by using an LED light source in the calibration method according to the embodiment, the instrumental difference in spectroscopic analysis by the optical emission spectrometer 100 can be further reduced.

[0048] Also, unlike a lamp light source, the light amount of the LED light source 21 can be freely adjusted by current control. Therefore, in the calibration method described above, if an LED light source that outputs continuous spectrum light in the wavelength range of 200 nm to 870 nm is used, calibration can be performed in the wavelength range of 200 nm to 870 nm.

[0049] FIG. 9 is a diagram showing an example of LED light output from an LED light source 21 according to an embodiment. The wavelength band of the LED light source 21 is preferably continuous spectrum light in the range of 200 nm to 870 nm. The LED light source may be configured by combining LED light sources having a plurality of different wavelength bands. The light output from the LED light source 21 is not limited to visible light, and may be ultraviolet light or infrared light. The LED light source 21 may be capable of outputting light of various wavelengths (colors) by combining with, for example, a white LED.

[0050] [Modification of LED fixture] As a modification of the LED jig, a wafer-type jig LW can be used instead of the LED jig 20. The wafer-type jig LW will be described with reference to Figs. 10 and 11. Fig. 10 is a diagram showing an example of a wafer-type jig LW according to the modification. Fig. 11 is a diagram for explaining the operation of a semiconductor manufacturing apparatus 30 according to the modification of the embodiment.

[0051] The fixture LW includes a base 11, a control board 12, a plurality of LED light sources 13a to 13d (collectively referred to as "LED light sources 13"), and a battery 19. The base 11 is a substrate, for example a disk-shaped wafer. A notch 22 is formed on the edge of the base 11. The shape of the base 11 is not limited to a polygonal or elliptical shape, as long as it can be transported by a transport device that transports a substrate. This allows the fixture LW to be transported by a transport device (transport arm, etc.) provided in the transport chamber in the calibration system according to the embodiment while maintaining the vacuum between the plasma processing device 10 and the transport chamber. The control board 12 is a circuit board provided on the base 11, and includes the LED light sources 13a to 13d, a connector 14, and a control circuit 200.

[0052] The LED light sources 13a to 13d are disposed on the control board 12 on the base 11. The LED light source 13a, the LED light source 13b, the LED light source 13c, and the LED light source 13d each emit light of a different wavelength (i.e., different color). The LED light sources 13a to 13d each have four LEDs that emit light of the same wavelength. By arranging four LEDs that emit light of the same wavelength side by side, the amount of light of each wavelength can be increased or decreased by changing the number of LEDs to be turned on. However, the number of LED light sources 13 for each wavelength is not limited to four, and may be any number greater than one. The control of turning on and off the LED light source 13 and the control of the current value are executed by the control circuit 200 upon receiving an instruction from the CPU 104. The control circuit 200 has a function of a control unit that controls each part of the jig LW. The control circuit 200 also has a function of a communication unit that communicates with the CPU 104.

[0053] The connector 14 is a connector for connecting to an external power source and charging the battery. For example, four batteries 19 are arranged on the base 11. The batteries 19 supply power to the LED light sources 13a to 13d and the control circuit 200. The number of batteries is not limited to four, and any number can be selected.

[0054] As shown in Fig. 11, the jig LW is transferred to the chamber 2 using a transfer device VA provided in a vacuum transfer chamber adjacent to the chamber 2 and a transfer device LA provided in an atmospheric transfer chamber communicating with the vacuum transfer chamber via a load lock chamber. The alignment device ORT is adjacent to the atmospheric transfer chamber. The wafer-type jig LW can be transferred by the transfer devices VA and LA, so that the jig LW can be transferred without opening the chamber 2 to the atmosphere.

[0055] Moreover, the jig LW is transported to the alignment device ORT, and the jig LW is rotated to identify the position of the jig LW using the notch 22. When the jig LW is placed on the mounting table ST, the desired LED light source 13 is controlled to approach the observation window 101. The above-mentioned transport control is executed by the control unit 180 upon receiving an instruction from the CPU 104.

[0056] Even when a wafer-type jig LW is used, the CPU 104 may control each calibration process for obtaining the reference calibration data, calculating the calibration formula, and calibrating the detection value, or the control unit 180 of the plasma processing device 10 may control each calibration process.

[0057] For example, the control unit 180 of the reference device 10c may control a process of placing a wafer-type jig LW by transporting the jig LW into a chamber of the reference device 10c, a process of changing the amount of light output from the LED light source of the placed wafer-type jig LW, and acquiring first data which is the emission intensity for each wavelength of the LED light whose amount of light has been adjusted in stages, and a process of storing the first data in a memory.

[0058] The control unit 180 of the calibration target device 10e may control a process of placing a wafer-type jig LW by transporting the jig LW into a chamber of the calibration target device 10e, a process of changing the amount of light output from the LED light source of the placed wafer-type jig LW, and acquiring second data which is the emission intensity for each wavelength of the LED light whose light amount has been adjusted in stages, and a process of calculating a calibration formula based on the first data and the second data stored in the memory.

[0059] According to the calibration method using the wafer-type jig LW, deviations in the detection values ​​of the optical emission spectrometer 100 attached to a plasma processing device 10 such as a mass production device are calibrated. This makes it possible to output detection values ​​that are consistent with the standard optical emission spectrometer 100, regardless of which optical emission spectrometer 100 is used.

[0060] Furthermore, light can be received by the optical emission spectrometer 100 while the LED light source 13 is inside the chamber 2. Furthermore, the jig LW can be transported into the chamber 2 while the inside of the chamber 2 is kept at a vacuum, without opening the lid and opening the chamber 2 to the atmosphere. This can improve productivity.

[0061] [LED light source according to modified example] In the above calibration method, an LED light source 21 that irradiates light in a wide wavelength band of 200 nm to 870 nm (hereinafter also referred to as broad light) is used as the irradiated reference light. The LED light source 21 according to the modified example described below can simultaneously irradiate two types of light: broad light and light having a peak in an arbitrary wavelength band. By performing the calibration method of the present disclosure using this LED light source 21, it is possible to simultaneously perform "sensitivity calibration" for calibrating the light in the wide wavelength band of the broad light, and "peak position calibration" for calibrating the light peak so that it is in the correct wavelength band using light having a peak.

[0062] An LED light source 21 that emits two types of light, broad light and light with a peak, will be described with reference to FIG. 12. When four LEDs with light peaks U, V, S, and T at wavelengths of 365 nm, 446 nm, 502 nm, and 608 nm are used, a continuous spectrum of optical signal intensity with four peaks as shown in FIG. 12(a) is obtained. In this way, a continuous spectrum can be created using multiple types of LEDs with different peaks. However, depending on the multiple types of LEDs used, there may be some areas where the optical signal intensity is insufficient for use in the calibration method of the present disclosure, as shown in the wavelength band between 365 nm and 446 nm in FIG. 12(a), for example.

[0063] The light peaks differ depending on the type of LED. Therefore, the distance between the light peaks (wavelengths) is made as close as about 40 nm, and four LEDs having light peaks U, P, V, and Q at 365 nm, 405 nm, 446 nm, and 470 nm are selected. In this case, a continuous spectrum of optical signal intensity having four peaks as shown in FIG. 12(b) is obtained. When creating a continuous spectrum using multiple LEDs having different peaks in this way, multiple types of LEDs are selected taking into consideration the peak intervals. This makes it possible to create a broad continuous spectrum of light having multiple peaks at a specified wavelength and having optical signal intensity of a specified level or higher in the target wavelength band using the selected multiple types of LEDs. The target wavelength band is preferably light that spreads over a wide band, for example, 200 nm to 870 nm.

[0064] From the above, by combining multiple types of LEDs with different peaks, a reference light in which light with clear multiple peaks and light spreading over the target wavelength band are mixed can be irradiated from one LED light source 21. The calibration method of the present disclosure is executed using this LED light source 21. This allows simultaneous "sensitivity calibration over the entire target wavelength band" for calibrating the light over the entire target wavelength band that the broad light has, and "calibration of the peak position" for calibrating the light peak so that it comes to the correct wavelength band using light with a peak. In other words, according to the calibration method of the present disclosure, the light detected by the optical emission spectroscopic analyzer 100 attached to the calibration target device can be calibrated to simultaneously perform "sensitivity calibration over the entire target wavelength band" and "calibration of the peak position".

[0065] In the above description, the LED light source 21 is described as constituting a continuous spectrum by combining multiple types of LEDs having peaks at different wavelengths. Note that multiple types of LEDs may be combined with a phosphor that is excited and emits light by the LED light, and the optical signal intensity of the continuous spectrum may be supplemented by the phosphor. For example, an LED light source 21 may be created that has broad light in a desired target wavelength band and constitutes a continuous spectrum with a peak in light by supplementing the optical signal intensity by combining multiple types of LEDs and phosphors.

[0066] [LED light source configuration] Next, the configuration of an LED light source 21 according to a modified example that irradiates reference light in which a plurality of clear peaks and light that spreads over a wide band in the target wavelength band are mixed will be described with reference to Fig. 13. Fig. 13 is a schematic exploded view of the LED light source 21.

[0067] The LED light source 21 includes a light collecting mechanism 201, a circuit board 202, and a cooling mechanism 203. On the circuit board 202, a plurality of types of LEDs 205a to 205f, a DC power supply 207, and a controller 208 are mounted. The LEDs 205a to 205f are also collectively referred to as LEDs 205. In FIG. 13, six types of LEDs 205a to 205f are mounted, but the number of LEDs 205 is not limited to this, and the number and types of LEDs 205 are determined so as to irradiate reference light in which a plurality of clear peaks and light that spreads over a wide band in the target wavelength band are mixed.

[0068] The LEDs 205a to 205f output light having different wavelength peaks. The DC power supply 207 supplies a DC current to each component provided on the circuit board 202. The controller 208 controls the turning on / off of the LEDs 205a to 205f mounted on the circuit board 202.

[0069] The constant current circuits 206a to 206f are provided for the LEDs 205a to 205f, respectively. The constant current circuits 206a to 206f are provided for the LEDs 205a to 205f, respectively. The constant current circuits 206a to 206f are circuits that control the output current to the LEDs 205a to 205f to be constant. The brightness of the LEDs 205 is determined by the current value. Therefore, if the current value supplied to the LEDs 205a to 205f fluctuates, the brightness of the LEDs 205 changes accordingly. Therefore, the constant current circuits 206a to 206f control the LEDs 205a to 205f to supply a constant current to each of them. This makes it possible to stabilize the intensity of the optical signals irradiated from the LEDs 205a to 205f. Furthermore, the peak positions of the light emitted by the LEDs 205a to 205f can be changed by adjusting the current values ​​of the constant current circuits 206a to 206f, thereby making it possible to adjust the color tone of the light emitted by the multiple LEDs.

[0070] The circuit board 202 on which the LEDs 205a to 205f are mounted has a multi-layer structure. FIG. 14 is a cross-sectional view of the circuit board 202 cut along the AA plane. The circuit board 202 has six ground layers L1 to L6 stacked from the top surface 202a on which the LEDs 205c are mounted downward. The cathode or anode electrode of the LEDs 205c is connected to the ground layers L1 to L6 via a metal wiring layer 220 that penetrates the circuit board 202 in the vertical direction directly below the LEDs 205c. This allows the heat generated by the LEDs 205c to be efficiently transferred to the ground layers L1 to L6. The ground layers L1 to L6 are made of metal, and transfer the heat generated by the LEDs 205c to the cooling mechanism 203 side, where it is efficiently dissipated.

[0071] When heat accumulates in the LED 205c, the light quantity of the LED 205c decreases. Therefore, the ground layers L1 to L6 function as a heat sink to dissipate the heat generated from the LED 205c. The ground layers L1 to L6 are made of metal and therefore dissipate heat easily. This allows the heat of the LED 205 to be efficiently dissipated from the ground layers L1 to L6 to the cooling mechanism 203. As a result, the LED light source 21 is configured not to change the characteristics of the LED 205c, such as the light quantity.

[0072] 14 shows only the lower structure of the LED 205c, the lower structures of the other LEDs 205 have the same configuration, and have a heat dissipation function due to the multi-layer structure of the ground layers L1 to L6 under each LED 205. The cooling mechanism 203 can use a heat sink, multiple Peltier elements, etc.

[0073] 13, the light collecting mechanism 201 collects the light emitted from each of the LEDs 205a to 205f using a mirror and a lens 212, etc. As a result, a mixture of light that spreads over a desired target wavelength band and light that has optical peaks at a plurality of different wavelengths is irradiated from the plurality of types of LEDs 205 mounted on the LED light source 21 toward the optical emission spectrometer 100 via the light collecting mechanism 201. As a result, the CPU 104 of the optical emission spectrometer 100 can calibrate the wavelength position of the light using the peak position of the light, and can calibrate the optical sensitivity using broad light in the target wavelength band.

[0074] The LED light source 21 may further include a phosphor 204 between the light collecting mechanism 201 and the circuit board 202. In this way, the optical signal intensity of the continuous spectrum of the light irradiated from the LED light source 21 may be supplemented by using the phosphor 204 that is excited and emits light by the light of the LED 205.

[0075] According to the calibration method and calibration system of the embodiment, it is possible to avoid errors in the detection results of the optical emission spectrometer 100 for each chamber due to the influence of mounting parts when the optical emission spectrometer 100 is connected to the chamber 2, and to reduce instrumental differences in spectroscopic analysis.

[0076] The calibration method and the calibration system according to the disclosed embodiments should be considered as illustrative and not restrictive in all respects. The above-described embodiments 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.

[0077] Although the plasma processing apparatus of the present disclosure has been described as a capacitively coupled plasma (CCP) processing apparatus, the present disclosure is not limited to this, and can be applied to any type of apparatus, including an atomic layer deposition (ALD) apparatus, an inductively coupled plasma (ICP), a radial line slot antenna (RLSA), an electron cyclotron resonance plasma (ECR), and a helicon wave plasma (HWP). [Explanation of symbols]

[0078] 2. Chamber 3…Top electrode 4…Lower electrode 5...Electrostatic chuck 10...Plasma processing device 20…LED fixture 13, 21...LED light source 30...Semiconductor manufacturing equipment 100...Emission spectroscopic analyzer 101...observation window 180...Control unit ST: Placement stand W…Substrate LW…Wafer-type LED fixture

Claims

1. Placing an LED light source having a given wavelength band within a reference device; A step of changing the amount of light output from the LED light source and acquiring first data which is the emission intensity for each wavelength at the light amount adjusted in a stepwise manner; storing the first data in a memory; placing the LED light source on a calibration target device; A step of changing the amount of light output from the LED light source and acquiring second data which is the emission intensity for each wavelength at the light amount adjusted in a stepwise manner; calculating a calibration equation based on the first data and the second data stored in the memory; A calibration method, including:

2. a step of calibrating an emission intensity detected by an emission spectrometer attached to the calibration target device based on the calibration formula to obtain third data; 2. The method of claim 1, comprising:

3. The emission intensity is the emission intensity of plasma in the calibration target device. The calibration method according to claim 2 .

4. The given wavelength band is set in the region of 200 nm to 870 nm; The calibration method according to any one of claims 1 to 3.

5. The LED light source is composed of a combination of LEDs having a plurality of different wavelength bands. The calibration method according to any one of claims 1 to 4.

6. The stepwise adjusted light amount output from the LED light source is determined by a current value for controlling the LED light source or the number of LEDs to be turned on in the LED light source. The calibration method according to any one of claims 1 to 5.

7. The LED light source combines a plurality of types of LEDs having different light peak wavelengths to emit light having a mixture of light having light peaks at a plurality of different wavelengths and light that spreads over a desired target wavelength band. The calibration method according to any one of claims 1 to 6.

8. using the LED light source to calibrate the light intensity detected by an optical emission spectrometer attached to the calibration target device, thereby simultaneously calibrating the position of the wavelength peak and the sensitivity of light spreading over a target wavelength band; The calibration method according to claim 7.

9. A calibration system having a reference device, a calibration target device, a control unit of the reference device, and a control unit of the calibration target device, The control unit of the master device Placing an LED light source having a given wavelength band within a reference device; A step of changing the amount of light output from the LED light source and acquiring first data which is the emission intensity for each wavelength at the light amount adjusted in a stepwise manner; storing the first data in a memory; configured to control The control unit of the calibration target device placing the LED light source on the calibration target device; A step of changing the amount of light output from the LED light source and acquiring second data which is the emission intensity for each wavelength at the light amount adjusted in a stepwise manner; calculating a calibration equation based on the first data and the second data stored in the memory; A calibration system configured to control the

10. The control unit of the calibration target device a step of calibrating an emission intensity detected by an emission spectrometer attached to the calibration target device based on the calibration formula to obtain third data; configured to control The calibration system of claim 9.

11. The control unit of the reference device and the control unit of the calibration target device are the same control unit. A calibration system according to claim 9 or 10.

12. The control unit of the reference device and the control unit of the calibration target device are different control units. A calibration system according to claim 9 or 10.

13. The LED light source includes a plurality of types of LEDs having different light peak wavelengths, and a plurality of constant current circuits provided for each of the plurality of types of LEDs. A calibration system according to any one of claims 9 to 12.

14. The peak positions of the light of the plurality of types of LEDs are individually adjusted by adjusting the current by the constant current circuit. The calibration system of claim 13.

15. A circuit board is provided with the LED light source mounted thereon, the circuit board has a multi-layer structure, the multi-layer structure including a ground layer; The plurality of types of LEDs are configured to dissipate heat through the ground layer. A calibration system according to claim 13 or 14.

16. The cathode electrodes or the anode electrodes of the plurality of types of LEDs are connected to the ground layer.

16. The calibration system of claim 15.

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