JP2017168298A - Plasma treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure, with a simple configuration, a space distribution of light emission intensities of plasma.SOLUTION: A plasma treatment apparatus comprises: a detection system 2 which detects, with the use of a focus variable lens 2b, the intensities of light generated by plasma at a plurality of spots in a treatment vessel 1a; and an adjustment control device 4 which controls an adjustment device 6a for individually adjusting, for each of relative spots in the treatment vessel 1a corresponding to each of the plurality of spots in the treatment vessel 1a, a physical quantity that changes during a plasma treatment. The focus variable lens 2b is a lens which changes its focal position in accordance with a voltage applied thereto. The detection system 2 sends, to the adjustment control device 4, a detection result indicating the spots where the light intensities are detected in the treatment vessel 1a as well as values of light intensities detected at the spots. The adjustment control device 4 controls the adjustment device 6a such that it adjusts the physical quantity on the basis of the spots and the light intensity values indicated by the detection result.SELECTED DRAWING: Figure 1

Description

Embodiments described herein relate generally to a plasma processing apparatus.

In recent years, in a plasma processing apparatus, for example, precise process control at a nano level is required. Various techniques for realizing such process control have been developed (Patent Documents 1 and 2). For example, the plasma processing apparatus described in Patent Document 1 aims to enable more precise process control by improving the in-plane uniformity of the processed shape of a wafer and reducing charge damage. A processing chamber, a high-frequency power source for generating plasma, a means for supplying gas to the processing chamber, a shower plate, an exhaust means for depressurizing the processing chamber, and a stage for placing the object to be processed And a focus ring, the gas temperature distribution in the processing chamber can be measured, the temperature of the focus ring can be adjusted, and the gas temperature in the surface of the object to be processed can be made uniform based on the measurement result of the gas temperature distribution Control the temperature of the focus ring.

In addition, the plasma processing apparatus described in Patent Document 2 enables more precise process control by making it possible to move the focal point of an optical system that detects the emission intensity of plasma. Monitor means for monitoring light emitted from the processing region via an optical system, and a condenser lens of the optical system is mounted and fixed on a moving mechanism including an X table, a Y table, and a Z table. With the plasma processing apparatus of Patent Document 2 having such a configuration, even if three emission peak points in the processing region fluctuate, the focal point of the condenser lens can coincide with the emission peak point by driving the moving mechanism. Become.

JP 2008-251866 A JP-A-5-206076

In plasma processing, unevenness may occur in plasma heat input to the wafer. This can be an impediment to precise process control. The unevenness of plasma heat input to the wafer corresponds to the spatial distribution of the plasma emission intensity. In the technique described in Patent Document 1, a plurality of condensing heads are used to obtain a spatial distribution of light emission intensity. In the technique described in Patent Document 2, a device for moving the condenser lens is provided in order to obtain a spatial distribution of emission intensity. As described above, in Patent Documents 1 and 2, a complicated configuration is required to obtain a detailed spatial distribution of the emission intensity of plasma. For this reason, a technique that enables measurement with a simple configuration for the spatial distribution of plasma emission intensity is desired.

In one aspect, a plasma processing apparatus is provided. The plasma processing apparatus includes a processing container in which plasma processing is performed and a single variable focus lens, and detects the light intensity of light emitted from plasma at a plurality of locations in the processing container using the variable focus lens. System, adjustment device for adjusting first physical quantity or second physical quantity changing during plasma processing individually for each corresponding location in a processing container corresponding to each of a plurality of locations, and adjustment control for controlling the adjustment device An apparatus. The variable focus lens is a lens that changes a focal position according to an applied voltage. The first physical quantity increases or decreases according to the increase or decrease of the light intensity. The second physical quantity increases or decreases the light intensity according to the increase or decrease of the second physical quantity. The detection system sends a detection result indicating the position where the light intensity is detected in the processing container and the value of the light intensity detected at the position to the adjustment control device. The adjustment control device controls the adjustment device to adjust the first physical quantity or the second physical quantity based on the location indicated by the detection result and the value of the light intensity. Therefore, the light intensity of the plasma at a plurality of locations in the processing container is detected using a single simple variable focus lens, and based on the detection result, the first is increased or decreased according to the increase or decrease of the light intensity during the plasma processing. Or a second physical quantity that can increase or decrease the light intensity during the plasma treatment is suitably adjusted. In addition, since the detection of the light intensity of the plasma at a plurality of locations in the processing container is performed through a simple variable focus lens, the time required for the detection of the light intensity at the plurality of locations in the processing container is shortened. In addition, since the time required to detect the light intensity at a plurality of locations in the processing container is shortened, the adjustment to the first physical quantity or the second physical quantity performed based on the detection result is performed in a relatively short time. obtain.

In one embodiment, in the plasma processing apparatus, the adjustment control apparatus stores correspondence data indicating the correspondence between the light intensity and the first physical quantity or the second physical quantity in the memory of the adjustment control apparatus, and the detection result indicates The value of the first physical quantity or the second physical quantity corresponding to the light intensity value is calculated using the corresponding data, and the calculated first physical quantity value or second physical quantity value and the detection result indicate The adjusting device is controlled to adjust the first physical quantity or the second physical quantity related to the location based on the location. Therefore, since the value of the first physical quantity or the second physical quantity corresponding to the light intensity detected by the detection system can be immediately calculated using the corresponding data, the first physical quantity performed based on the detection result or Adjustment to the second physical quantity can also be performed in a shorter time.

In one embodiment, in the plasma processing apparatus, the detection system converts light output from the variable focus lens into electric charge, receives the electric charge output from the photoelectric conversion element that outputs the electric charge, and the electric charge. A detection control device that sends a signal indicating the amount of received charge to the adjustment control device and adjusts the focal position of the variable focus lens by applying a voltage to the variable focus lens. Therefore, the detection of the light intensity at a plurality of locations in the processing container can be reliably performed by the single focus variable lens by the photoelectric conversion element and the detection control device.

In one embodiment, the plasma processing apparatus further includes a mounting table that is disposed in the processing container and on which a wafer to be processed by the plasma processing is mounted. The mounting table includes a main surface on which the wafer is mounted, and an adjustment device that individually adjusts the temperature of each region of the main surface corresponding to each of a plurality of locations. The temperature adjusted by the adjusting device is a first physical quantity that increases or decreases according to the increase or decrease of the light intensity. The adjustment control device controls the adjustment device so as to individually adjust the temperature of each region of the main surface corresponding to each of the plurality of locations based on the detection result. Therefore, when the first physical quantity is the temperature of the main surface on which the wafer is mounted, the light intensity of the plasma detected through one variable focus lens is used to adjust the temperature at a plurality of locations on the main surface. This can be done easily. The light intensity of the plasma corresponds to the uneven heat input of the plasma, and the temperature at multiple locations on the main surface is adjusted using the light intensity of the plasma. The temperature can be suitably adjusted so as to be maintained regardless of unevenness.

In one embodiment, a plasma processing apparatus includes: a plurality of upper electrodes arranged facing a lower electrode provided on a mounting table above a mounting table on which a wafer to be processed in plasma processing is mounted; And a plurality of adjusting devices for individually adjusting the power for plasma excitation supplied to each of the upper electrodes. The plasma excitation power adjusted by the adjusting device is the second physical quantity, and increases or decreases the light intensity according to the increase or decrease of the power. The adjustment control device controls each of the plurality of adjustment devices so as to individually adjust the power for plasma excitation supplied to each of the plurality of upper electrodes corresponding to each of the plurality of locations based on the detection result. Therefore, when the second physical quantity is the power for plasma excitation, the adjustment of the power supplied to the upper electrode is performed by using the light intensity of the plasma detected through one variable focus lens, Easy to do. The light intensity of the plasma corresponds to uneven heat input of the plasma. For example, by adjusting the power for plasma excitation so as to maintain the light intensity of the plasma uniformly over a plurality of locations in the processing vessel, Thermal unevenness can be suitably reduced.

As described above, it is possible to measure the spatial distribution of the plasma emission intensity with a simple configuration.

FIG. 1 is a cross-sectional view showing a main configuration of a plasma processing apparatus according to an embodiment. FIG. 2 is a diagram schematically illustrating a main configuration of the plasma processing apparatus according to the first embodiment. FIG. 3 is an exploded view of the main configuration of the stage according to the first embodiment. 4 includes a part (a) and a part (b). The part (a) in FIG. 4 is a view of the appearance of the heat exchanger according to the first embodiment as viewed from one side. (B) part is the figure which looked at the external appearance of the heat exchanger which concerns on Example 1 from the reverse side of the said one side. 5 includes (a) part, (b) part, and (c) part, and (a) part of FIG. 5 is a plan view of the cell part according to Example 1, and (b) of FIG. The part is the figure which looked at the appearance of the cell part concerning Example 1 from one side, and the (c) part of Drawing 5 shows the appearance of the cell part concerning Example 1 from the opposite side of the above-mentioned one side. FIG. FIG. 6 is a diagram illustrating a main configuration of the flow path unit according to the first embodiment. FIG. 7 is a graph showing an example of an actual measurement result used to create correspondence data according to the first embodiment, and shows a correlation between the temperature of the wafer and the light intensity of light emitted from plasma. FIG. 8 is a cross-sectional view of the main configuration of the plasma processing apparatus according to the second embodiment. FIG. 9 is a diagram schematically illustrating main configurations of the microwave output unit according to the second embodiment and the antenna module according to the second embodiment. FIG. 10 is a plan view illustrating an appearance of the microwave supply unit according to the second embodiment. FIG. 11 is a graph showing an example of an actual measurement result used to create the correspondence data according to the second embodiment, and shows a correlation between the power applied to the microwave radiating unit and the light intensity of the light emitted from the plasma. .

With reference to FIGS. 1-11, the structure of the plasma processing apparatus which concerns on one Embodiment is demonstrated. The same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted.

FIG. 1 is a diagram schematically illustrating a main configuration of a plasma processing apparatus according to an embodiment. The plasma processing apparatus 100 includes a processing container 1a and a mounting table 1b, and further includes a detection system 2, an adjustment control device 4, an adjustment device 6a, and a measurement device 6b. The detection system 2 includes a window 2a, a single variable focus lens 2b, a spectroscope 2c, and a detection control device 2d.

The processing container 1a is subjected to plasma processing. The processing container 1a defines a processing space 1a1 in which plasma processing is performed. The mounting table 1b is disposed in the processing container 1a. The mounting table 1b includes a stage 1c and an electrostatic chuck 1d. The mounting table 1b includes a main surface 1b1. A wafer W is placed on the mounting table 1b. The mounting table 1b includes a main surface 1b1 on which the wafer W is mounted. The wafer W is a processing target of plasma processing.

The detection system 2 determines the light intensity (for example, the amount of light per unit time) emitted by plasma at a plurality of locations (for example, the detection location PN1, the detection location PN2, the detection location PN3, etc. shown in FIG. 1) in the processing container 1a. To detect. The detection system 2 includes a location (for example, the detection location PN1, the detection location PN2, the detection location PN3, etc. shown in FIG. 1) where the light intensity of the plasma is detected in the processing container 1a and the value of the light intensity detected at the location. Is sent to the adjustment control device 4. The detection system 2 may have a two-dimensional or three-dimensional spatial resolution for light intensity detection. The detection system 2 can have a three-dimensional spatial resolution for light of a plurality of wavelengths.

The window 2a is provided in an opening provided on the side wall of the processing container 1a. The processing space 1a1 communicates with the outside (the variable focus lens 2b) of the processing container 1a through the opening and the window 2a. For example, quartz may be used as the material of the window 2a.

The variable focus lens 2b is optically connected to the window 2a. The variable focus lens 2b receives light in the processing container 1a that enters through the window 2a. The variable focus lens 2b is connected to the spectroscope 2c through an optical fiber. The variable focus lens 2b is connected to the detection control device 2d via an electric signal line. The focus variable lens 2b changes the focus position according to the applied voltage. The variable focus lens 2b can be, for example, a liquid lens.

The spectroscope 2c is connected to the detection control device 2d via an electric signal line. The spectroscope 2c is connected to the variable focus lens 2b through an optical fiber. The spectroscope 2c includes not only a slit and a grating, but also a photoelectric conversion element 2c1. When the photoelectric conversion element 2c1 receives the light output from the variable focus lens 2b through the slit and grating sequentially, the photoelectric conversion element 2c1 converts the received light into an electric charge and outputs the electric charge to the detection control device 2d.

The detection control device 2d is connected to the adjustment control device 4 via an electric signal line. Although not shown, the detection control device 2d includes a CPU, a ROM, and a RAM. When the CPU executes a computer program stored in the ROM, the detection control device 2d applies a voltage to the variable focus lens 2b to adjust the focus position of the variable focus lens 2b, and outputs it from the photoelectric conversion element 2c1. A signal indicating the amount of the received charge (in one embodiment, the amount of charge corresponding to the light intensity described above) is sent to the adjustment control device 4.

In one embodiment, the place where the detection system 2 detects light is mainly the place on the wafer W and in the plasma PA1. The variable focus lens 2b can focus on an arbitrary point included in the reference plane PA2 in the processing container 1a under the control of the detection control device 2d. The reference surface PA2 extends parallel to the wafer W and intersects with the variable focus lens 2b. A location where light is detected by the detection system 2 is defined as a detection location PNi (i represents a natural number of 1 or more and is a symbol for identifying a location where light is detected by the detection system 2. The same applies hereinafter. ). The detection location PNi is in the processing space 1a1 and is included in the reference plane PA2. Each of the detection location PN1, the detection location PN2, and the detection location PN3 shown in FIG. 1 is an example of the detection location PNi, and is not limited to the three locations illustrated. Each of the detection point PN1, the detection point PN2, and the detection point PN3 passes through the reference line PA3, the reference line PA4, and the reference line PA5. The reference line PA3, the reference line PA4, and the reference line PA5 are parallel to each other and orthogonal to the reference plane PA2. The axial directions of the reference line PA3, the reference line PA4, and the reference line PA5 are all directions in which the wafer W is viewed from above the wafer W. Note that the number of reference lines such as the reference line PA3 is the same as the number of detection points PNi, and is not limited to the three illustrated.

The detection control device 2d detects the light intensity by controlling the focal position of the variable focus lens 2b for each detection point PNi at a preset time interval (for example, an interval of several nanoseconds), and detects the detected light intensity. Then, a detection result indicating the detected detection point PNi is sent to the adjustment control device 4.

The adjustment control device 4 is connected to the adjustment device 6a and the measurement device 6b via an electric signal line. Although not shown, the adjustment control device 4 includes a CPU and a ROM. The adjustment control device 4 further includes a memory 4a, in which correspondence data 4a1 and target value data 4a2 created in advance are stored in a readable manner. The adjustment control device 4 transmits and receives signals among the detection control device 2d, the adjustment device 6a, and the measurement device 6b. The adjustment control device 4 uses the various data stored in the memory 4a and the measurement result sent from the measurement device 6b to execute control of the adjustment device 6a by the CPU executing a computer program stored in the ROM. Etc. The adjusting device 6a individually adjusts the first physical quantity or the second physical quantity that changes during the plasma processing for each corresponding location in the processing container 1a corresponding to each of the plurality of detection locations PNi. The first physical quantity is an amount that increases / decreases in accordance with the increase / decrease of the light intensity detected by the detection system 2, and may be, for example, the temperature of the wafer W or the like. When the adjusting device 6a adjusts the first physical quantity, the measuring device 6b measures the first physical quantity, transmits the measurement result to the adjustment control device 4, and the adjusting device 6a adjusts the second physical quantity. In this case, the second physical quantity is measured and the measurement result is transmitted to the adjustment control device 4. The adjustment control device 4 instructs the adjustment device 6a to adjust the first physical quantity or the second physical quantity by feedback control based on the measurement result (which may further include a set value) transmitted from the measurement device 6b. . The temperature of the wafer W is, for example, the same as the temperature of the main surface 1b1 of the electrostatic chuck 1d, the temperature of the interface between the stage 1c and the electrostatic chuck 1d, and the like. The second physical quantity is an amount by which the light intensity detected by the detection system 2 is increased or decreased according to the increase or decrease of the second physical quantity, and can be, for example, power for plasma excitation. The adjustment control device 4 uses the first physical quantity or the second physical value based on the location (the detection location PN1 or the like) indicated by the detection result output from the detection control device 2d and the value of the light intensity detected by the detection system 2. The adjusting device 6a is controlled so as to adjust the physical quantity.

More specifically, the adjustment control device 4 stores correspondence data 4a1 indicating correspondence between the light intensity detected by the detection system 2 and the first physical quantity or the second physical quantity in the memory 4a. Using data 4a1 (further, using target value data 4a2 stored in the memory 4a and indicating a target value for the light intensity, first physical quantity, or second physical quantity detected by the detection system 2 ), The first physical quantity value or the second physical quantity value corresponding to the light intensity value indicated by the detection result sent from the detection system 2 is calculated, and the calculated first physical quantity value or second physical quantity is calculated. The adjustment device 6a is controlled so as to adjust the first physical quantity or the second physical quantity related to the location based on the value of and the location indicated by the detection result (detected location PN1 or the like).

Although not shown in FIG. 1, the plasma processing apparatus 100 includes various apparatuses necessary for performing plasma processing, such as a gas supply system, a lower electrode, and an upper electrode. As the processing gas used for the plasma processing, a suitable gas such as an inert gas such as Ar can be used.

Next, a calculation method for calculating the set values of the first physical quantity and the second physical quantity using the correspondence data 4a1 and the target value data 4a2 will be described. The calculation method described below is continuously performed in a predetermined cycle (for example, a lot unit, a wafer unit, a recipe step unit, a unit of several seconds to several nsec, etc., and a suitable cycle can be used). This is performed by the adjustment control device 4. The adjustment control device 4 sets the first physical quantity or the second physical quantity to the set value calculated by the calculation process, thereby setting the first physical quantity or the second physical quantity to a predetermined target value (target value data). (Target value indicated by 4a2). The calculation by the calculation method is realized by the CPU of the adjustment control device 4 executing a computer program stored in the ROM of the adjustment control device 4.

First, when the correspondence data 4a1 is data indicating the correspondence between the light intensity detected by the detection system 2 (the light intensity of light emitted from the plasma in the processing container 1a during the plasma processing) and the first physical quantity. A calculation method will be described. The first physical quantity is an amount that increases or decreases according to the increase or decrease of the light intensity detected by the detection system 2, and may be the temperature of the wafer W, for example. The value of the light intensity detected by the detection system 2 at the detection location PNi is I (i) (the unit of I (i) is an arbitrary unit [au], and therefore will be omitted below. i) is an average value of a value for about 3 seconds, for example, by the detection system 2, and the same shall apply hereinafter.), and the first physical quantity corresponding to I (i) is T (i) And That is, the value of the first physical quantity that can be detected when the light intensity value I (i) is detected by the detection system 2 is T (i). The correspondence between I (i) and T (i) indicated by the correspondence data 4a1 is set for each detection location PNi based on actual measurement. For example, as a linear function, I (i) = α (i) × T (I) + β (i) (Formula 1). α (i) and β (i) are constants specified based on actual measurement. When control is performed to maintain the first physical quantity at the target value T0 (= T (i), i is arbitrary), assuming that the value of I (i) corresponding to T0 is I0 (i), I0 (i ) = Α (i) × T0 + β (i) (Formula 2). When the setting value of the first physical quantity that the adjustment control device 4 instructs the adjustment device 6a is T1 (i), T1 (i) is expressed as ΔT (i) = T0−T (i) (Equation 3) , T1 (i) = T0 + ΔT (i) (Expression 4). If Expression 1 to Expression 4 are used, T1 (i) = 2 × T0− (I (i) −β (i)) / α (i) (Expression 5) is obtained. Equation 3 represents the difference between the target value T0 of the first physical quantity and the value (T (i)) of the first physical quantity obtained based on the detection result by the detection system 2. Expression 4 represents that the set value T1 (i) of the first physical quantity is a value that is offset from the target value T0 of the first physical quantity by the difference (ΔT (i)). Equation 5 indicates that the first physical quantity setting value T1 (i) is obtained by the first physical quantity target value T0 and the light intensity value I (i) indicated by the detection result by the detection system 2. ing. The adjustment control device 4 instructs the adjustment device 6a to set the first physical quantity set value T1 (i), thereby passing through the first physical quantity value T (i) after an interval of, for example, several nanoseconds to several milliseconds. ) Can be adjusted to the target value T0 of the first physical quantity.

Next, when the correspondence data 4a1 is data indicating the correspondence between the light intensity detected by the detection system 2 (the light intensity of light emitted from the plasma in the processing container 1a during the plasma processing) and the second physical quantity. The calculation method will be described. The second physical quantity is an amount by which the light intensity detected by the detection system 2 is increased or decreased according to the increase or decrease of the second physical quantity, and can be, for example, power for plasma excitation. Let E (i) be a second physical quantity corresponding to the light intensity value I (i) detected by the detection system 2 at the detection location PNi. That is, the value of the second physical quantity that can be detected when the light intensity value I (i) is detected by the detection system 2 is E (i). The correspondence between I (i) and E (i) indicated by the correspondence data 4a1 is set for each detection location PNi based on actual measurement. For example, as a linear function, I (i) = η (i) × E (I) + θ (i) (Expression 6) η (i) and θ (i) are constants specified based on actual measurement. When control is performed to maintain the light intensity detected by the detection system 2 at the target value I0 (= I (i), i is arbitrary), the value of E (i) corresponding to I0 is set to E0 (i). Then, I0 = η (i) × E0 (i) + θ (i) (Expression 7) is established. Therefore, if the setting value of the second physical quantity instructed by the adjustment control device 4 to the adjustment device 6a is E1 (i), E1 (i) becomes ΔE (i) = E0 (i) −E (i). (Equation 8) is used to express E1 (i) = E0 (i) + ΔE (i) (Equation 9). If Expression 6 to Expression 9 are used, E1 (i) = (2 × I0−I (i) −θ (i)) / η (i) (Expression 10) is obtained. Formula 8 represents the difference between the target value E0 (i) of the second physical quantity and the value (E (i)) of the second physical quantity obtained based on the detection result by the detection system 2. Expression 9 represents that the setting value E1 (i) of the second physical quantity is a value that is offset from the target value E0 of the second physical quantity by the difference (ΔE (i)). Expression 10 indicates that the setting value E1 (i) of the second physical quantity is obtained by the target value I0 of the second physical quantity and the light intensity value I (i) indicated by the detection result by the detection system 2. ing. The adjustment control device 4 instructs the adjustment device 6a to set the second physical quantity set value E1 (i), and thereby, for example, passes the light intensity value I (i) through an interval of several nanoseconds to several milliseconds. The light intensity can be adjusted to the target value I0.

Note that the correspondence relationship between the light intensity (I (i)) and the first physical quantity (T (i)) or the second physical quantity (E (i)) included in the correspondence data 4a1 is expressed by Equations 1, 2, and These are not limited to linear functions as shown in equations 6 and 7, but may be associated with other functions. The variable focus lens 2b is assumed to focus on a single point, but is not limited thereto, and can be focused on a line segment (a line segment included in the reference line PA3 or the like). is there.

According to the plasma processing apparatus 100 according to the embodiment described above, the light intensity of plasma is detected at a plurality of locations (detection locations PNi) in the processing container 1a using a simple single variable focus lens 2b. Based on the detection result, the first physical quantity that increases or decreases according to the increase or decrease of the light intensity during the plasma processing or the second physical quantity that can increase or decrease the light intensity during the plasma processing is suitably adjusted. Moreover, since the detection of the light intensity of the plasma at a plurality of locations (detection locations PNi) in the processing container 1a is performed via a single focus variable lens 2b, a plurality of locations (detection locations PNi) in the processing container 1a. The time required for detecting the light intensity at is reduced. In addition, since the time required to detect the light intensity at a plurality of locations (detection locations PNi) in the processing container 1a is shortened, the adjustment to the first physical quantity or the second physical quantity performed based on the detection result is relatively performed. Can be done in a short time.

Further, since the first physical quantity value or the second physical quantity value corresponding to the light intensity detected by the detection system 2 can be immediately calculated using the correspondence data 4a1, the first physical quantity performed based on the detection result is performed. Adjustment to the physical quantity or the second physical quantity can also be performed in a shorter time.

Furthermore, the detection of light intensity at a plurality of locations (detection locations PNi) in the processing container 1a can be reliably performed by the single variable focus lens 2b by the photoelectric conversion element 2c1 and the detection control device 2d.

(Embodiment 1) A plasma processing apparatus A50 according to Embodiment 1 will be described with reference to FIGS. In Example 1, the first physical quantity in the above-described embodiment is used, and the temperature (T [° C.]) of the wafer W is used as the first physical quantity. In Example 1, the plasma processing apparatus 100, the processing container 1a, the stage 1c, the electrostatic chuck 1d, the processing space 1a1, and the main surface 1b1 in the above-described embodiment are respectively the plasma processing apparatus A50, the processing container A52, and the stage A97. , Electrostatic chuck A54, processing space A93, and main surface A54a. The mounting table 1b according to the above-described embodiment corresponds to a configuration including the stage A97 and the electrostatic chuck A54 in Example 1. In Example 1, the detection system 2 and the adjustment control device 4 in the above-described embodiment are provided, and further, the temperature detector A43a, the temperature detector A43b, and the temperature detector A43c are provided. The adjusting device 6a in the above-described embodiment corresponds to the chiller unit A42 in Example 1, and the measuring device 6b corresponds to the temperature detector A43a, the temperature detector A43b, and the temperature detector A43c in Example 1. ing. The adjustment control device 4 is provided as a configuration different from the control unit A98, but may be included in the control unit A98.

FIG. 2 is a diagram schematically illustrating a main configuration of the plasma processing apparatus A50 according to the first embodiment. The plasma processing apparatus A50 is a capacitively coupled parallel plate plasma etching apparatus and includes a substantially cylindrical processing container A52. The processing container A52 is made of, for example, aluminum obtained by anodizing the surface of the processing container A52. The processing container A52 is grounded.

A stage A97 is disposed on the bottom of the processing container A52. As shown in FIG. 3, the stage A97 includes a plate A2, a case A4, a heat exchanger A6, and a flow path part A8.

The plate A2 is provided with a temperature detector A43a, a temperature detector A43b, and a temperature detector A43c. The temperature detector A43a, the temperature detector A43b, and the temperature detector A43c face the interface (surface A2a) between the electrostatic chuck A54 and the plate A2, and the temperature of the interface (the temperature is the same as that of the electrostatic chuck A54). The temperature of the main surface A 54 a and the temperature of the wafer W are detected), and the detection result is transmitted to the adjustment control device 4.

The stage A97 will be described in detail with reference to FIG. FIG. 3 is an exploded view of the main configuration of the stage A97 according to the first embodiment. The plate A2 has a disk shape and is made of a metal such as aluminum. The plate A2 includes a front surface A2a and a back surface A2b. An electrostatic chuck A54 is provided on the surface A2a of the plate A2, and the wafer W is placed on the main surface A54a of the electrostatic chuck A54.

Case A4 is comprised, for example with metals, such as stainless steel, and is provided with side wall A4a and bottom wall A4b. The side wall A4a has a cylindrical shape, and defines an accommodation space A94 inside the side wall A4a. The side wall A4a extends along the cylindrical axis direction, and supports the plate A2 from the back surface A2b side of the plate A2. The bottom wall A4b is connected to the lower end of the side wall A4a (the end opposite to the end of the side wall A4a where the plate A2 is disposed). An O-ring A10 that extends annularly along the upper end surface A4c can be provided on the upper end surface A4c of the side wall A4a (the surface of the end of the side wall A4a on which the plate A2 is disposed). The plate A2 is airtightly fixed to the upper end surface A4c through, for example, an O-ring A10 by screwing. Thus, the accommodation space A94 is defined from above (the side opposite to the bottom wall A4b in the accommodation space A94) by the plate A2. A supply pipe A12 and a recovery pipe A14 are provided on the side wall A4a. The supply pipe A12 extends along the radial direction of the side wall A4a, and communicates with the accommodation space A94 via the first opening A16. The collection pipe A14 extends along the radial direction of the side wall A4a, and communicates with the accommodation space A94 via the second opening A18. In the accommodation space A94, the flow path portion A8 and the heat exchanger A6 are accommodated. A flow path part A8 is provided in the bottom wall A4b, and a heat exchanger A6 is provided in the flow path part A8. A bottom wall A4b, a channel portion A8, and a heat exchanger A6 are sequentially arranged along the cylindrical axis direction of the side wall A4a. Both the channel portion A8 and the heat exchanger A6 have a cylindrical shape similar to the shape of the accommodation space A94. The cylindrical axis of the flow path part A8 and the heat exchanger A6 is common and coincides with the cylindrical axis of the side wall A4a.

With reference to FIG. 4 and FIG. 5, the heat exchanger A6 will be described in detail. FIG. 4 includes (a) part and (b) part, and (a) part of FIG. 4 is a view of the appearance of the heat exchanger A6 according to the first embodiment as viewed from one side (above). 4B is a view of the appearance of the heat exchanger A6 according to the first embodiment as viewed from the opposite side (downward) of the one side. As shown in FIG. 4, the heat exchanger A6 includes a partition wall A20, a plurality of first pipes A22, and a plurality of second pipes A24. The heat exchanger A6 supplies the heat exchange medium individually to the plurality of areas on the back surface A2b of the plate A2 that are two-dimensionally distributed and not included in each other, and the supplied heat exchange medium is It is configured so that it can be collected. The partition wall A20 has a disk shape or a cylindrical shape as a whole, and includes a plurality of substantially hexagonal columnar cell portions A95 extending in the central axis direction of the partition wall A20.

One cell portion A95 of the plurality of cell portions A95 is shown in FIG. 5 includes (a) part, (b) part, and (c) part, and (a) part of FIG. 5 is a plan view of cell part A95 according to Example 1, and (b) of FIG. ) Part is a view of the appearance of the cell part A95 according to Example 1 from one side, and part (c) of FIG. 5 shows the appearance of the cell part A95 according to Example 1 on the one side. It is the figure seen from the other side. The cell parts A95 are joined to each other so as to form a honeycomb structure in plan view from above the partition wall A20. The cell portion A95 defines a space A96 having a hexagonal cross section. That is, the partition wall A20 forms a plurality of spaces A96. The space A96 is two-dimensionally distributed below the plate A2 (on the back surface A2b of the plate A2 and facing the heat exchanger A6) and does not include each other.

Each of the first tubes A22 extends through a substantially central position of the corresponding space A96 in plan view. The first tube A22 extends toward the back surface A2b of the plate A2. Each of the first pipes A22 is surrounded by a partition wall A20 that defines a space around the first pipe A22. Each of the first pipes A22 includes a first opening end A22a and a second opening end A22b. The first opening end A22a is disposed so as to face the back surface A2b of the plate A2. The second opening end A22b is located on the opposite side of the first opening end A22a, and is located below the space A96 (on the opposite side to the back surface A2b side of the plate A2). The first pipe A22 functions as a pipe that receives the heat exchange medium from the chiller unit A42 and discharges the heat exchange medium from the first opening end A22a into the space A96.

The second pipe A24 is connected to the partition wall A20 so as to communicate with the space A96. An opening A24a is provided at the lower end of each second pipe A24 (the end of the second pipe A24 on the side opposite to the side connected to the space A96). The second pipe A24 functions as a pipe for discharging the heat exchange medium discharged from the first opening end A22a of the first pipe A22 into the space A96 to the outside. In the heat exchanger A6 having the above-described configuration, the first pipe A22, the partition wall A20 that defines the space A96 surrounding the first pipe A22, and the second pipe A24 that communicates with the space A96 are heat exchanged. Parts. Therefore, the heat exchanger A6 includes a plurality of heat exchange units arranged two-dimensionally so as not to be included in each other along the surface of the partition wall A20 of the heat exchanger A6 (along the back surface A2b of the plate A2).

In one embodiment, the heat exchanger A6 may be configured with a resin as a main component. In addition, in order to change intensity | strength and heat conductivity, the material which comprises heat exchanger A6 can be changed partially. For example, the first open ends A22a of the plurality of first pipes A22 can be made of a resin containing carbon. Thereby, the intensity | strength of 1st opening end A22a can be raised especially.

Next, the flow path part A8 will be described. FIG. 6 is a diagram illustrating a main configuration of the flow path portion A8 according to the first embodiment. The flow path part A8 is disposed below the heat exchanger A6 (on the side where the heat exchanger A6 is disposed), a flow path for supplying a heat exchange medium to the heat exchanger A6, and a heat exchanger And a flow path for recovering the heat exchange medium from A6.

As shown in FIG. 6, the channel portion A8 is a substantially cylindrical block body, and includes an upper surface A8a and a side surface A8b. The channel portion A8 includes a first aggregate portion A29 and a second aggregate portion A30 that protrude from the side surface A8b. The flow path part A8 includes a plurality of first flow paths A26 that penetrate the inside of the flow path part A8, and a plurality of second flow paths A28 that penetrate the inside of the flow path part A8. That is, the channel portion A8 includes a plurality of small-diameter cavities (a plurality of small diameters) penetrating the inside of the channel portion A8 from the upper surface A8a of the channel portion A8 toward the first aggregate portion A29 and the second aggregate portion A30. A first flow path A26 and a plurality of second flow paths A28) are formed.

The first flow path A26 includes one end A26a and the other end A26b. One end A26a of the first flow path A26 is provided at a position corresponding to the plurality of first pipes A22 of the heat exchanger A6 on the upper surface A8a of the flow path part A8, and the second end of the first pipe A22. Connected to the open end A22b. The other end A26b of the first flow path A26 is collected in the first aggregate A29. The first collecting portion A29 is provided at a position corresponding to the first opening A16 of the case A4, and faces the first opening A16 in a state of being accommodated in the case A4.

The second flow path A28 includes one end A28a and the other end A28b. One end A28a of the second flow path A28 is provided at a position corresponding to the opening A24a of the second pipe A24 of the heat exchanger A6 on the upper surface A8a of the flow path part A8, and the opening of the second pipe A24. Connected to A24a. The other end A28b of the second flow path A28 is collected in the second aggregate A30. The second aggregate portion A30 is provided at a position corresponding to the second opening A18 of the case A4, and faces the second opening A18 in a state of being accommodated in the case A4.

In the channel portion A8, the first channel A26 and the second channel A28 are provided as independent channels that do not communicate with each other. The first flow path A26 and the second flow path A28 can communicate with each other via the heat exchanger A6.

Returning to FIG. 2, the configuration of the plasma processing apparatus A50 will be described. An electrostatic chuck A54 is provided on the surface A2a of the plate A2 of the stage A97. The electrostatic chuck A54 has a structure in which an electrode A56, which is a conductive film, is disposed between a pair of insulating layers or insulating sheets. A direct current power source A58 is electrically connected to the electrode A56. The electrostatic chuck A54 can electrostatically hold the wafer W by electrostatic force generated by a DC voltage from the DC power supply 58. The electrostatic chuck A54 includes a main surface A54a. The wafer W is placed on the main surface A54a.

The plasma processing apparatus A50 includes a plurality of first pipes A40a and a plurality of second pipes A40b. Each of the plurality of first pipes A40a is connected to the other end A26b of each of the plurality of first flow paths A26 via the supply pipe A12 of the case A4. Each of the plurality of second pipes A40b is connected to the other end A28b of each of the plurality of second flow paths A28 via the recovery pipe A14 of the case A4. The other ends of the plurality of first pipes A40a and the plurality of second pipes A40b are connected to a chiller unit A42 provided outside the processing container A52. A heat exchange medium having a predetermined temperature is circulated and supplied from the chiller unit A42 to the stage A97 via the plurality of first pipes A40a and the plurality of second pipes A40b. The heat exchange medium is a fluid that circulates in the stage A97 for the purpose of exchanging heat with the plate A2, and includes a refrigerant that absorbs heat from the plate A2 and a heat medium that gives heat to the plate A2. is there. As the heat exchange medium, a liquid such as water or a fluorinated liquid, a gas, or the like can be used. The heat exchange medium supplied from the chiller unit A42 passes from one end of the one flow path to the other end (the first pipe A40a, the supply pipe A12, the plurality of first flow paths A26, and the plurality of first pipes A22. The plurality of second pipes A24, the plurality of second flow paths A28, the recovery pipes A14, and the second pipes A40b) are returned to the chiller unit A42. By controlling the temperature of the heat exchange medium circulated in this way, the temperature of the wafer W placed on the main surface A54a of the electrostatic chuck A54 can be locally adjusted. The chiller unit A42 is individually connected to the plurality of first flow paths A26 via a plurality of independent flow paths, and independently controls the temperature of the heat exchange medium supplied to the plurality of first flow paths A26. And control. Similarly, the chiller unit A42 is individually connected to a plurality of second flow paths A28 via a plurality of mutually independent flow paths. According to the configuration of the first embodiment, the temperature of the heat exchange medium discharged from the plurality of first pipes A40a is individually controlled.

An upper electrode A60 is provided in the processing container A52. The upper electrode A60 is disposed to face the plate A2 above the plate A2 functioning as the lower electrode, and the plate A2 and the upper electrode A60 are provided in parallel to each other. A processing space A93 in which plasma is generated is defined between the upper electrode A60 and the plate A2.

The upper electrode A60 is supported on the upper part of the processing container A52 via an insulating shielding member A62. The upper electrode A60 can include an electrode plate A64 and an electrode support A66. The electrode plate A64 faces the processing space A93, and defines a plurality of gas discharge holes A64a. The electrode plate A64 can be made of a low-resistance conductor or semiconductor with little Joule heat. The electrode plate A64 is grounded.

The electrode support A66 detachably supports the electrode plate A64, and can be made of a conductive material such as aluminum. The electrode support A66 may have a water cooling structure. A gas diffusion chamber A66a is provided in the electrode support A66. A plurality of gas flow holes A66b communicating with the gas discharge holes A64a extend downward from the gas diffusion chamber A66a. The electrode support A66 is formed with a gas introduction port A66c that guides the processing gas to the gas diffusion chamber A66a, and a gas supply pipe A68 is connected to the gas introduction port A66c.

A gas source A70 is connected to the gas supply pipe A68 via a valve A72 and a mass flow controller A74 (MFC). Note that an FCS may be provided instead of the MFC. The gas source A70 is a gas source of the processing gas. The processing gas from the gas source A70 reaches the gas diffusion chamber A66a from the gas supply pipe A68, and is discharged into the processing space A93 through the gas flow hole A66b and the gas discharge hole A64a.

The plasma processing apparatus A50 includes a ground conductor A52a. The ground conductor A52a is a substantially cylindrical ground conductor, and is provided so as to extend above the height position of the upper electrode A60 from the side wall of the processing vessel A52.

In the plasma processing apparatus A50, a deposition shield A76 is detachably provided along the inner wall of the processing container A52. The deposition shield A76 is also provided on the outer periphery of the stage A97. The deposition shield A76 prevents the etching byproduct (depot) from adhering to the processing container A52, and can be constituted by coating an aluminum material with ceramics such as Y ₂ O ₃ .

On the bottom side of the processing container A52, an exhaust plate A78 is provided between the stage A97 and the inner wall of the processing container A52. The exhaust plate A78 can be configured by, for example, coating an aluminum material with ceramics such as Y ₂ O ₃ . An exhaust port A52e is provided in the processing container A52 below the exhaust plate A78. An exhaust device A80 is connected to the exhaust port A52e via an exhaust pipe A53. The exhaust device A80 includes a vacuum pump such as a turbo molecular pump, and can reduce the pressure inside the processing vessel A52 to a desired degree of vacuum. The loading / unloading port A52g for the wafer W is provided on the side wall of the processing container A52. The loading / unloading port A52g can be opened and closed by a gate valve A81.

In one embodiment, the plasma processing apparatus A50 further includes a high frequency power source A92a, a high frequency power source A92b, a matching unit A91a, and a matching unit A91b. The high frequency power source A92a generates high frequency power for plasma generation, and supplies a frequency of 27 [MHz] or higher, for example, 40 [MHz], to the plate A2 via the matching unit A91a. The matching unit A91a includes a circuit that matches the internal (or output) impedance of the high-frequency power source A92a with the load impedance. The high frequency power source A92b generates a high frequency bias power for ion attraction, and a high frequency bias power of 13.56 [MHz] or less, for example, 3 [MHz] is applied to the plate A2 through the matching unit A91b. Supply. The matching unit A91b includes a circuit that matches the internal (or output) impedance of the high-frequency power source A92b with the load impedance. The lower electrode may be provided separately from the plate A2.

In the configuration of the first embodiment, the plasma processing apparatus A50 may further include a control unit A98. The control unit A98 is a computer including a processor, a storage unit, an input device, a display device, and the like, and controls each unit of the plasma processing apparatus A50, such as a power supply system, a gas supply system, and a drive system. In the control unit A98, an operator can perform a command input operation or the like to manage the plasma processing apparatus A50 by using an input device, and the operating state of the plasma processing apparatus A50 can be visualized by a display device. Can be displayed. Further, the storage unit of the control unit A98 causes the respective components of the plasma processing apparatus A50 to execute processes according to a control program for controlling various processes executed by the plasma processing apparatus A50 by the processor and processing conditions. A program for processing, that is, a processing recipe is stored.

The mounting table according to the first embodiment having the above-described configuration includes a main surface A54a on which the wafer W is mounted, and a plurality of locations (in the first embodiment, the light intensity of light emitted by plasma in the processing container A52 is detected. The temperature of each region of the main surface A54a corresponding to each of the detection locations PNi detected by the system 2 (in the first embodiment, a reference line PA3 extending in the direction of viewing the wafer W from above the wafer W through the detection location PNi). And an adjusting device (chiller unit A42) for individually adjusting the temperature of the region where the crossing and the like intersect the main surface A54a. Based on the detection result of the detection system 2, the adjustment control device 4 has a main surface corresponding to each of a plurality of locations (detection locations PNi in which the light intensity of the light emitted by the plasma in the processing container A52 is detected by the detection system 2). The chiller unit A42 is controlled so as to individually adjust the temperature of each area of A54a (the temperature of the area where the reference line PA3 etc. extending in the direction of viewing the wafer W from above the wafer W through the detection point PNi intersects the main surface A54a). To do. The temperature adjusted by the chiller unit A42 is the temperature of the main surface A54a, and is a first physical quantity (T [T] that increases or decreases according to the increase or decrease of the light intensity of the light emitted from the plasma generated in the processing container A52 during the plasma processing. ° C]). The temperature of the main surface A54a is the same as the temperature of the wafer W, and is the same as the temperature at the interface between the electrostatic chuck A54 and the plate A2 (which is a mutual contact surface, the surface A2a). The detected temperature is detected by the provided temperature detector A43a or the like, and the detection result is sent from the temperature detector A43a or the like to the adjustment control device 4.

Next, a specific example of the setting value (T (i) [° C.]) of the first physical quantity calculated by the adjustment control device 4 according to the first embodiment will be described. FIG. 7 is a graph showing an example of an actual measurement result used to create the correspondence data 4a1 according to the first embodiment. The temperature of the wafer W (T (i = 1) [° C.]) and the light emitted by the plasma are shown. The correlation with light intensity (I (i = 1)) is shown. The actual measurement result shown in FIG. 7 shows the light intensity of the detection location PN1 detected by the detection system 2 according to the first embodiment and the temperature detected by the temperature detector A43a corresponding to the detection location PN1 (the temperature is the main surface). And the temperature of the interface between the electrostatic chuck A54 and the detection system 2 and the temperature of the wafer W). The horizontal axis in FIG. 7 represents T (1) [° C.], and the vertical axis in FIG. 7 represents I (1). An example of the target value data 4a2 is assumed to be T0 = 80 [° C.]. Corresponding data 4a1 obtained based on the actual measurement result shown in FIG. 7 is the above-described formula 1 (α (1) = 10, β (1) = 0), and is represented by the line segment SL1 shown in FIG. When α (1) = 10, β (1) = 0, and T0 = 80 [° C.], Equation 5 for determining the set value T1 (1) [° C.] is T1 (1) = 2 × T0− (I (1) −β (1)) / α (1) = 160−I (1) / 10 [° C.].

For example, when the light intensity value I (1) = 1235 at the detection location PN1, the temperature of the region corresponding to the detection location PN1 (the reference line PA3 extending in the direction of passing through the detection location PN1 and viewing the wafer W from above the wafer W) The set value T1 (1) [° C.] for the temperature of the region intersecting the main surface A54a and the temperature detected by the temperature detector A43a (measuring device 6b) is T1 (1) = 160−1235 / 10 = 36.5 [° C.]. As another example, when the value I (1) = 1192 of the light intensity at the detection location PN1, the temperature of the region corresponding to the detection location PN1 (the direction in which the wafer W is viewed from above the wafer W through the detection location PN1). The set value T1 (1) [° C.] with respect to the temperature detector A43a (temperature detected by the measuring device 6b) is T1 (1) = 160. −1192 / 10 = 40.8 [° C.].

According to the first embodiment described above, when the first physical quantity is the temperature of the main surface A54a on which the wafer W is mounted, the temperature at a plurality of locations on the main surface A54a (through the detection locations PNi and above the wafer W). The temperature of the region where the reference line PA3 etc. extending in the direction of viewing the wafer W from the main surface A54a is adjusted easily by using the light intensity of the plasma detected through the single variable focus lens 2b. Yes. The light intensity of the plasma corresponds to the heat input unevenness of the plasma, and the temperature at the plurality of locations on the main surface A54a is adjusted using the light intensity of the plasma. The temperature can be suitably adjusted so as to be maintained regardless of unevenness.

(Embodiment 2) A plasma processing apparatus B100 according to Embodiment 2 will be described with reference to FIGS. In Example 2, the second physical quantity in the above-described embodiment is used, and the plasma excitation power [watt] supplied to the microwave radiation unit B43 is used as the second physical quantity. In Example 2, each of the plasma processing apparatus 100, the processing container 1a, the stage 1c, the electrostatic chuck 1d, and the processing space 1a1 in the above-described embodiment includes the plasma processing apparatus B100, the chamber B1, the support member B12, the susceptor B11, This corresponds to each of the processing spaces B5. The mounting table 1b according to the above-described embodiment corresponds to a configuration including the susceptor B11 and the support member B12 in the second embodiment. In Example 2, the detection system 2 and the adjustment control device 4 in the above-described embodiment are provided. The adjusting device 6a in the above-described embodiment corresponds to the amplifier unit B42 in the second example, and the measuring device 6b corresponds to the detection system 2 in the second example. In addition, although the adjustment control apparatus 4 is provided as a structure different from the control part B140, it can also be included in the control part B140.

FIG. 8 is a cross-sectional view of the main configuration of the plasma processing apparatus B100 according to the second embodiment. FIG. 9 is a diagram schematically illustrating main configurations of the microwave output unit B30 according to the second embodiment and the antenna module B41 according to the second embodiment. FIG. 10 is a plan view illustrating an appearance of the microwave supply unit B40 according to the second embodiment.

The plasma processing apparatus B100 is configured as a plasma etching apparatus that performs, for example, an etching process as a plasma process on the wafer W. The plasma processing apparatus B100 includes a chamber B1 and a microwave plasma source B2. The chamber B1 has a substantially cylindrical shape made of a metal material such as aluminum or stainless steel that is airtight, is grounded, and includes an opening B1a. The opening B1a is provided in the upper part of the chamber B1. The chamber B1 defines a processing space B5 in which plasma is generated. The microwave plasma source B2 forms a microwave plasma in the chamber B1. The microwave plasma source B2 is provided so as to face the inside of the chamber B1 from the opening B1a.

The plasma processing apparatus B100 further includes a susceptor B11, a support member B12, an insulating member B12a, a matching unit B13, a high-frequency bias power supply B14, an exhaust pipe B15, an exhaust apparatus B16, an inlet / outlet B17, a gate valve B18, a support ring B29, and a gas supply. A source B110, a gas pipe B111, a slot B122, an annular dielectric member B126, and a controller B140 are provided.

A susceptor B11 for horizontally supporting a semiconductor wafer W, which is an object to be processed, is supported in the chamber B1 by a cylindrical support member B12 provided upright via an insulating member B12a at the center of the bottom of the chamber B1. It is provided in the state. Examples of the material constituting the susceptor B11 and the support member B12 include aluminum whose surface is anodized (anodized), ceramics such as AlN, and the like.

The susceptor B11 has a function of an electrostatic chuck for electrostatically attracting the wafer W. The susceptor B <b> 11 is also provided with a temperature control mechanism, a gas flow path for supplying heat transfer gas to the back surface of the wafer W, lifting pins that move up and down to transport the wafer W, and the like. A high frequency bias power source B14 is electrically connected to the susceptor B11 via a matching unit B13. By supplying high frequency power from the high frequency bias power source B14 to the susceptor B11, ions in the plasma are attracted to the wafer W side. As described above, the susceptor B11 constitutes a lower electrode disposed to face the upper electrode of the microwave radiation unit B43.

An exhaust pipe B15 is connected to the bottom of the chamber B1, and an exhaust apparatus B16 including a vacuum pump is connected to the exhaust pipe B15. By operating the exhaust device B16, the inside of the chamber B1 is exhausted, and the inside of the chamber B1 can be decompressed at a high speed to a predetermined degree of vacuum. On the side wall of the chamber B1, a loading / unloading port B17 for loading / unloading the wafer W and a gate valve B18 for opening / closing the loading / unloading port B17 are provided.

The microwave plasma source B2 includes a microwave output unit B30 and a microwave supply unit B40. The microwave output unit B30 distributes the microwaves to a plurality of paths and outputs them. The microwave supply unit B40 transmits the microwave output from the microwave output unit B30 and radiates it into the chamber B1.

As shown in FIG. 9, the microwave output unit B30 includes a microwave power source B31, a microwave oscillator B32, an amplifier B33 that amplifies the oscillated microwave, and a distributor that distributes the amplified microwave to a plurality of parts. B34. The microwave oscillator B32 causes, for example, PLL oscillation of a microwave having a predetermined frequency (for example, 915 [MHz]). The distributor B34 distributes the microwave amplified by the amplifier B33 while matching the impedance between the input side and the output side in order to suppress the loss of the microwave. As the microwave frequency, in addition to 915 [MHz], 700 [MHz] to 3 [GHz] can be used.

The microwave supply unit B40 includes a plurality of antenna modules B41 and a microwave radiation antenna B45. The antenna module B41 includes an amplifier unit B42 and a microwave radiation unit B43. The antenna module B41 guides the microwave distributed by the distributor B34 into the chamber B1. The microwave supply unit B40 includes seven antenna modules B41. On the surface of the microwave radiation antenna B45 that is circular in plan view, six microwave radiation portions B43 are arranged at equal intervals along the circumference of the circle, and at the center of the circle. One microwave radiating part B43 is arranged. (FIG. 10).

The amplifier unit B42 mainly amplifies the distributed microwaves and supplies power for plasma excitation to each of the plurality of microwave radiation units B43. Microwave radiation part B43 comprises an upper electrode. The amplifier unit B42 includes a phase shifter B46, a variable gain amplifier B47, a main amplifier B48 constituting a solid state amplifier, and an isolator B49. The phase shifter B46 is configured to change the phase of the microwave, and the radiation characteristic can be modulated by adjusting the phase of the microwave. For example, the plasma distribution can be changed by controlling the directivity by adjusting the phase for each antenna module. Further, circularly polarized waves can be obtained by shifting the phase by 90 ° between adjacent antenna modules. The phase shifter B46 can be used for the purpose of spatial synthesis in the tuner by adjusting delay characteristics between components in the amplifier. Note that the phase shifter 46 does not need to be provided when such modulation of the radiation characteristics or adjustment of the delay characteristics between the components in the amplifier is unnecessary.

The variable gain amplifier B47 is an amplifier for adjusting the power level of the microwave input to the main amplifier B48 and adjusting the plasma intensity. By changing the variable gain amplifier B47 for each antenna module, the generated plasma can be distributed.

The main amplifier B48 constituting the solid state amplifier may be configured to include, for example, an input matching circuit, a semiconductor amplifying element, an output matching circuit, and a high Q resonance circuit.

The isolator B49 separates reflected microwaves reflected by the microwave radiation antenna B45 and directed to the main amplifier B48, and includes a circulator and a dummy load (coaxial terminator). The circulator guides the microwave reflected by the microwave radiation antenna B45 to the dummy load, and the dummy load converts the reflected microwave guided by the circulator into heat.

The microwave radiating antenna B45 is provided in a state of being hermetically sealed to a support ring B29 provided at the upper portion of the chamber B1, and can radiate microwaves and introduce gas. The microwave radiation antenna B45 is configured as a ceiling wall of the chamber B1. The microwave radiating antenna B45 is connected to the above-described plurality of microwave radiating portions B43, has a shower structure for discharging a plasma generation gas and a processing gas, and a gas pipe B111 extending from the gas supply source B110 is a microwave. It is connected to the radiation antenna B45. The plasma generation gas introduced from the microwave radiation antenna B45 into the chamber B1 is turned into plasma by the microwave radiated from the microwave radiation antenna B45, and is introduced into the chamber B1 from the microwave radiation antenna B45 by this plasma. The processing gas is excited and plasma of the processing gas is generated. The microwave plasma source B2 includes a gas supply source B110 that supplies a plasma generation gas for generating plasma, a processing gas for performing a film forming process and an etching process, and the like.

As the plasma generation gas, a rare gas such as Ar gas can be suitably used. Various processing gases such as a film forming process and an etching process can be adopted depending on the processing contents.

As described above, the plasma processing apparatus B100 according to the second embodiment includes the susceptor B11 above the mounting table (including the susceptor B11 and the support member B12) on which the wafer W to be processed is mounted. A plurality of upper electrodes arranged to face the lower electrode provided are provided. The plasma processing apparatus B100 according to the second embodiment includes a plurality of adjustment devices (amplifier units B42) that individually adjust the power for plasma excitation supplied to each of the plurality of upper electrodes (microwave radiation units B43). Prepare. The plasma excitation power adjusted by the amplifier unit B42 is the second physical quantity, and the light intensity of the light emitted by the plasma is increased or decreased according to the increase or decrease of the power. Based on the detection result, the adjustment control device 4 corresponds to each of a plurality of locations (in the second embodiment, detection locations PNi in which the light intensity of the light emitted by the plasma in the chamber B1 is detected by the detection system 2). The plasma excitation power supplied to each of the upper electrodes (microwave radiation part B43) (in Example 2, crosses the reference line PA3 etc. extending in the direction of viewing the wafer W from above the wafer W through the detection point PNi. A plurality of adjusting devices (amplifier units) for individually adjusting the power supplied to the microwave radiating unit B43, in other words, the power supplied to the microwave radiating unit B43 closest to the detection point PNi. B42) is controlled.

Next, a specific example of the setting value (E (i) [watt]) of the second physical quantity calculated by the adjustment control device 4 according to the second embodiment will be described. FIG. 11 is a graph illustrating an example of an actual measurement result used to create the correspondence data 4a1 according to the second embodiment. The power applied to the microwave radiation unit B43 (E (i = 1) [Watt]). And the light intensity (I (i = 1)) of the light emitted by the plasma. The actual measurement result shown in FIG. 11 shows the light intensity of the detection location PN1 detected by the detection system 2 according to the second embodiment and the application of the microwave radiation unit B43 corresponding to the detection location PN1 and obtaining the light intensity. Correlation with power. The horizontal axis of FIG. 11 represents E (1) [watt], and the vertical axis of FIG. 11 represents I (1). An example of the target value data 4a2 is assumed to be I0 = 1200. Corresponding data 4a1 obtained based on the actual measurement result shown in FIG. 11 is the above-described equation 6 (η (1) = 0.47, θ (1) = 24.72), and is represented by the line segment SL2 shown in FIG. expressed. Using η (1) = 0.47, θ (1) = 24.72, and I0 = 1200, Equation 10 for determining the set value E1 (1) [watts] is E1 (1) = (2 × I0− I (1) −θ (1)) / η (1) = (2400−I (1) −24.72) /0.47 [watts].

For example, when the light intensity value I (1) = 1235 at the detection location PN1, the power applied to the microwave radiation unit B43 corresponding to the detection location PN1 (the wafer W is viewed from above the wafer W through the detection location PN1). The electric power supplied to the microwave radiating part B43 intersecting the reference line PA3 extending in the direction, in other words, the electric power supplied to the microwave radiating part B43 closest to the detection point PN1, and the electric power is regulated and controlled. The setting value E1 (1) [Watt] is adjusted by the amplifier unit B42 according to the control of the apparatus 4. E1 (1) = (2400-1235-24.72) /0.47=2426 [Watt] ]. As another example, when the value I (1) = 1192 of the light intensity at the detection location PN1, the power applied to the microwave radiation unit B43 corresponding to the detection location PN1 (through the detection location PN1 and the wafer W It is the power supplied to the microwave radiation part B43 intersecting with the reference line PA3 extending in the direction of viewing the wafer W from above, in other words, the power supplied to the microwave radiation part B43 closest to the detection point PN1. The electric power is adjusted by the amplifier unit B42 according to the control of the adjustment control device 4. The setting value E1 (1) [watt] for E1 (1) = (2400-1192-24.72) / 0 47 = 2518 [Watts].

According to the second embodiment described above, when the second physical quantity is the power for plasma excitation, the adjustment of the power supplied to the microwave radiating unit B43 is performed via one focus variable lens 2b. This can be done easily by using the detected light intensity of the plasma. The light intensity of the plasma corresponds to the uneven heat input of the plasma. For example, the power for plasma excitation is adjusted so as to maintain the light intensity of the plasma uniformly over a plurality of locations (detection locations PNi) in the chamber B1. Thus, the heat input unevenness of plasma can be suitably reduced.

While the principles of the invention have been illustrated and described in the preferred embodiments, it will be appreciated by those skilled in the art that the invention can be modified in arrangement and detail without departing from such principles. The present invention is not limited to the specific configuration disclosed in the present embodiment. We therefore claim all modifications and changes that come within the scope and spirit of the following claims.

DESCRIPTION OF SYMBOLS 100 ... Plasma processing apparatus, 1a ... Processing container, 1a1 ... Processing space, 1b ... Mounting stand, 1b1 ... Main surface, 1c ... Stage, 1d ... Electrostatic chuck, 2 ... Detection system, 2a ... Window, 2b ... Variable focus lens 2c ... Spectroscope, 2c1 ... Photoelectric conversion element, 2d ... Detection control device, 4 ... Adjustment control device, 4a ... Memory, 4a1 ... Corresponding data, 4a2 ... Target value data, 6a ... Adjustment device, 6b ... Measurement device, A10 ... O-ring, A12 ... supply pipe, A14 ... collection pipe, A16 ... first opening, A18 ... second opening, A2 ... plate, A20 ... partition wall, A22 ... first pipe, A22a ... first opening end A22b ... second open end, A24 ... second tube, A24a ... opening, A26 ... first flow path, A26a ... one end, A26b ... other end, A28 ... second flow path, A28a ... one end Part, A28b ... the other end A29 ... first collecting portion, A2a ... front surface, A2b ... back surface, A30 ... second collecting portion, A4 ... case, A40a ... first piping, A40b ... second piping, A42 ... chiller unit, A43a ... temperature Detector, A43b ... Temperature detector, A43c ... Temperature detector, A4a ... Side wall, A4b ... Bottom wall, A4c ... Upper end surface, A50 ... Plasma processing apparatus, A52 ... Processing vessel, A52a ... Ground conductor, A52e ... Exhaust port, A52g ... carry-in / out port, A53 ... exhaust pipe, A54 ... electrostatic chuck, A54a ... main surface, A56 ... electrode, A58 ... DC power supply, A6 ... heat exchanger, A60 ... upper electrode, A62 ... insulating shielding member, A64 ... Electrode plate, A64a ... gas discharge hole, A66 ... electrode support, A66a ... gas diffusion chamber, A66b ... gas flow hole, A66c ... gas inlet, A68 ... gas supply pipe, A70 ... gas Source, A72 ... Valve, A74 ... Mass flow controller, A76 ... Depot shield, A78 ... Exhaust plate, A8 ... Flow path part, A80 ... Exhaust device, A81 ... Gate valve, A8a ... Top surface, A8b ... Side, A91a ... Matching unit, A91b ... matching unit, A92a ... high frequency power supply, A92b ... high frequency power supply, A93 ... processing space, A94 ... accommodating space, A95 ... cell part, A96 ... space, A97 ... stage, A98 ... control part, B1 ... chamber, B100 ... plasma Processing device, B11 ... susceptor, B110 ... gas supply source, B111 ... gas piping, B12 ... support member, B122 ... slot, B126 ... annular dielectric member, B12a ... insulating member, B13 ... matching unit, B14 ... high frequency bias power supply, B140: Control unit, B15: Exhaust pipe, B16: Exhaust device, B17: Loading / unloading port, B18 ... Gate valve, B1a ... Opening, B2 ... Microwave plasma source, B29 ... Support ring, B30 ... Microwave output part, B31 ... Microwave power supply, B32 ... Microwave oscillator, B33 ... Amplifier, B34 ... Distributor, B40 ... microwave supply section, B41 ... antenna module, B42 ... amplifier section, B43 ... microwave radiation section, B45 ... microwave radiation antenna, B46 ... phase shifter, B47 ... variable gain amplifier, B48 ... main amplifier, B49 ... isolator, B5 ... processing space, PA1 ... plasma, PA2 ... reference plane, PA3 ... reference line, PA4 ... reference line, PA5 ... reference line, PN1 ... detection location, PN2 ... detection location, PN3 ... detection location, SL1 ... line segment, SL2 ... Line segment, W ... Wafer.

Claims (5)

A processing vessel in which plasma processing is performed;
A detection system comprising a single variable focus lens, and detecting the light intensity of light emitted by plasma at a plurality of locations in the processing container using the variable focus lens;
An adjusting device that individually adjusts the first physical quantity or the second physical quantity that changes during the plasma processing for each corresponding location in the processing container corresponding to each of the plurality of locations;
An adjustment control device for controlling the adjustment device;
With
The variable focus lens is a lens that changes a focal position according to an applied voltage,
The first physical quantity increases or decreases according to the increase or decrease of the light intensity,
The second physical quantity increases or decreases the light intensity according to an increase or decrease of the second physical quantity,
The detection system sends a detection result indicating the position where the light intensity is detected in the processing container and the value of the light intensity detected at the position to the adjustment control device,
The adjustment control device controls the adjustment device to adjust the first physical quantity or the second physical quantity based on the location indicated by the detection result and the value of the light intensity.
Plasma processing equipment. The adjustment control device stores correspondence data indicating the correspondence between the light intensity and the first physical quantity or the second physical quantity in a memory of the adjustment control apparatus, and the light intensity indicated by the detection result is stored in the memory. A value of the first physical quantity or a value of the second physical quantity corresponding to a value is calculated using the corresponding data, and the calculated value of the first physical quantity or the value of the second physical quantity and the detection Controlling the adjusting device to adjust the first physical quantity or the second physical quantity related to the location based on the location indicated by the result;
The plasma processing apparatus according to claim 1. The detection system includes:
A photoelectric conversion element that converts light output from the variable focus lens into electric charge and outputs the electric charge;
The electric charge output from the photoelectric conversion element is received, a signal indicating the amount of the received electric charge is sent to the adjustment control device, and a voltage is applied to the variable focus lens to adjust the focal position of the variable focus lens. A detection control device;
The plasma processing apparatus of Claim 1 or 2 provided with these. The apparatus further includes a mounting table disposed in the processing container and on which a wafer to be processed by the plasma processing is mounted;
The mounting table includes a main surface on which the wafer is mounted, and an adjustment device that individually adjusts the temperature of each region of the main surface corresponding to each of the plurality of locations.
The temperature adjusted by the adjusting device is the first physical quantity that increases or decreases according to the increase or decrease of the light intensity,
The adjustment control device controls the adjustment device to individually adjust the temperature of each region of the main surface corresponding to each of the plurality of locations based on the detection result.
The plasma processing apparatus as described in any one of Claims 1-3. Above the mounting table on which the wafer to be processed in the plasma processing is mounted, a plurality of upper electrodes arranged to face the lower electrode provided on the mounting table;
A plurality of adjusting devices for individually adjusting the power for plasma excitation supplied to each of the plurality of upper electrodes;
Further comprising
The power for plasma excitation adjusted by the adjusting device is the second physical quantity, and increases or decreases the light intensity according to increase or decrease of the power,
Each of the plurality of adjustment devices adjusts the electric power for plasma excitation supplied to each of the plurality of upper electrodes corresponding to each of the plurality of locations based on the detection result. To control the
The plasma processing apparatus as described in any one of Claims 1-3.

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