JP5798677B2 - Substrate processing apparatus and substrate processing method - Google Patents

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for performing plasma processing on a substrate such as a semiconductor wafer.

  In the manufacturing process of a semiconductor device, plasma processing such as etching and film formation is repeatedly performed for the purpose of forming a fine circuit pattern on a substrate such as a semiconductor wafer. In plasma processing, for example, plasma is generated by applying a high-frequency voltage between electrodes arranged opposite to each other in a processing chamber of a substrate processing apparatus configured to be depressurized, and plasma is applied to a substrate mounted on a mounting table. Etching is performed.

  During such plasma processing, the focus ring surrounds the periphery of the substrate on the mounting table in order to perform uniform and good processing at the edge portion (peripheral portion) as well as the center portion (center portion) of the substrate. Etching is performed on the mounting table. In this case, the substrate is provided with a substrate holding portion for electrostatically holding the substrate at the top of the mounting table and a heat transfer gas such as He gas on the back of the substrate in order to prevent temperature rise due to heat input from the plasma. The substrate temperature is kept constant by increasing the thermal conductivity with the susceptor.

JP-A-10-303288

  However, during the plasma treatment, not only the substrate but also the focus ring around it is exposed to the plasma, so the temperature of the focus ring may fluctuate due to the heat input of the plasma. This may affect the in-plane processing characteristics (process characteristics such as etching rate) of the substrate.

  In this regard, in order to prevent the characteristic correction ring provided around the substrate from accumulating heat due to repeated plasma processing and changing the processing characteristics around the substrate, the characteristic correction ring is also electrostatically held and Some heat transfer gases supplied to the back surface are branched and supplied to the back surface of the characteristic correction ring (see, for example, Patent Document 1).

  However, just supplying heat transfer gas to the back surface of the substrate and the back surface of the characteristic correction ring as in Patent Document 1, depending on the substrate processing conditions (gas type, gas flow rate, processing chamber pressure, high frequency power). May not be able to control the in-plane processing characteristics of the substrate. In Patent Document 1, since the same type of heat transfer gas can be supplied to both the back surface of the substrate and the back surface of the characteristic correction ring at the same pressure, the in-plane processing characteristics of the substrate cannot be freely controlled by the heat transfer gas. .

  Therefore, the present invention has been made in view of such problems, and an object of the present invention is to control the temperature of the focus ring independently of the temperature of the substrate. An object of the present invention is to provide a substrate processing apparatus capable of freely controlling processing characteristics.

  In order to solve the above-described problem, according to one aspect of the present invention, a substrate processing apparatus is provided in which a substrate is disposed in a processing chamber, a focus ring is disposed so as to surround the substrate, and plasma processing is performed on the substrate. A mounting table including a substrate mounting surface on which the substrate is mounted, a susceptor having a focus ring mounting surface on which the focus ring is mounted, a susceptor temperature adjusting mechanism for adjusting the temperature of the susceptor, A substrate holding portion that electrostatically attracts the back surface of the substrate to the substrate mounting surface and electrostatically attracts the back surface of the focus ring to the focus ring mounting surface, and a first heat transfer gas to the back surface of the substrate. A heat transfer gas supply mechanism provided independently with a first heat transfer gas supply unit for supplying and a second heat transfer gas supply unit for supplying a second heat transfer gas to the back surface of the focus ring; The The substrate processing apparatus is provided to symptoms.

  According to the present invention, the substrate can be electrostatically attracted to the substrate mounting surface of the substrate holder, and the focus ring can be electrostatically attracted to the focus ring mounting surface. In addition, a first heat transfer gas supply unit that supplies the first heat transfer gas to the back surface of the substrate and a second heat transfer gas supply unit that supplies the second heat transfer gas to the back surface of the focus ring are provided independently. Thus, the second heat transfer gas can be supplied to the back surface of the focus ring independently of the first heat transfer gas supplied to the back surface of the substrate. As a result, the thermal conductivity with the temperature-controlled susceptor can be changed independently, and the temperature of the focus ring can be controlled independently of the substrate temperature, so that the in-plane processing characteristics of the substrate can be improved or freely controlled. And can be controlled.

  In addition, the heat transfer gas supply mechanism is configured such that, for example, a first gas flow path connected to the first heat transfer gas supply section and a second gas flow path connected to the second heat transfer gas supply section are independent. The first gas flow path communicates with a plurality of gas holes provided in the substrate placement surface, and the second gas flow path communicates with a plurality of gas holes provided in the focus ring placement surface. Configure to communicate. As a result, the thermal conductivity between the substrate and the susceptor is separately controlled by the first heat transfer gas from the gas holes on the substrate mounting surface and the focus ring by the second heat transfer gas from the gas holes on the focus ring mounting surface. Can be controlled.

  In this case, a first annular diffusion portion comprising an annular space along the circumferential direction of the focus ring is provided below the focus ring placement surface, and the focus ring placement surface is provided above the first annular diffusion portion. The plurality of gas holes may be communicated with each other, and the second gas flow path may be communicated with a lower portion of the first annular diffusion portion. According to this, by supplying the second heat transfer gas to the first annular diffusion portion via the second gas flow path, the second heat transfer gas is entirely distributed along the circumferential direction of the first annular diffusion portion. Since it can be ejected from each gas hole while being diffused, it can be distributed evenly over the entire back surface of the focus ring.

  In addition, the heat transfer gas supply mechanism independently includes a first gas flow path connected to the first heat transfer gas supply section and a second gas flow path connected to the second heat transfer gas supply section. The first gas flow path communicates with a plurality of gas holes provided in the substrate mounting surface, and the second gas flow path is formed on a surface of the focus ring mounting surface in a circumferential direction of the focus ring. You may comprise so that it may communicate with the 2nd cyclic | annular spreading | diffusion part which consists of a cyclic | annular recessed part provided along. According to this, since the second heat transfer gas can be diffused along the circumferential direction in the entire second annular diffusion portion immediately below the back surface of the focus ring, it can be distributed evenly over the entire back surface of the focus ring.

  In this case, a plurality of protrusions that support the back surface of the focus ring may be formed in the second annular diffusion portion. According to this, a plurality of protrusions can be brought into direct contact with the back surface of the focus ring for heat transfer. As a result, it is possible to increase the portion that directly contacts the back surface of the focus ring and transfers heat.

  Further, a groove portion may be formed in the lower portion of the second annular diffusion portion along the circumferential direction, and the second gas flow path may be communicated with the groove portion. According to this, even when the number of the protrusions of the second annular diffusion portion is large and difficult to diffuse, the second heat transfer gas from the second gas flow channel diffuses in the circumferential direction through the groove portion. It becomes easy to reach the entire annular diffusion portion.

  In addition, the heat transfer gas supply mechanism independently includes a first gas flow path connected to the first heat transfer gas supply section and a second gas flow path connected to the second heat transfer gas supply section. The first gas flow path communicates with a plurality of gas holes provided in the substrate mounting surface, and the second gas flow path allows the second heat transfer gas to flow through the focus ring mounting surface. Alternatively, a portion having a rough surface may be formed along the circumferential direction of the focus ring and communicated with the portion. According to this, the second heat transfer gas from the second gas flow path can be diffused through the rough surface of the focus ring mounting surface over the circumferential direction of the focus ring.

  In this case, a seal portion for sealing the second heat transfer gas may be provided on both the inner peripheral side and the outer peripheral side of the focus ring mounting surface. According to this, since the second heat transfer gas can be made difficult to leak from the focus ring mounting surface, the heat transfer effect by the second heat transfer gas itself of the focus ring is thereby increased, thereby processing the edge portion of the substrate. Properties can be controlled.

  Moreover, you may make it eliminate the seal part of the one or both of the inner peripheral side of the said focus ring mounting surface, and an outer peripheral side. According to this, not only the heat transfer effect by the second heat transfer gas itself but also the second heat transfer gas can be leaked in the vicinity of the edge portion of the substrate, so the ratio of the gas component in the vicinity of the edge portion is changed. This also makes it possible to control the processing characteristics of the edge portion of the substrate.

  In addition, a sprayed coating is formed on the surface of the focus ring mounting surface and the surface of the substrate mounting surface, and the thermal spray coating of the focus ring mounting surface is against the porosity of the sprayed coating on the substrate mounting surface. The in-plane processing characteristics of the substrate may be controlled by changing the porosity. In this case, the porosity of the spray coating on the focus ring mounting surface is preferably determined according to the control temperature range of the susceptor.

  The plurality of gas holes in the substrate mounting surface are provided separately in a center region and an edge region around the center region, and the first gas flow path has a plurality of gas in the center region on the substrate mounting surface. The second gas flow path branches into two flow paths, one flow path communicates with a plurality of gas holes provided in the focus ring mounting surface, and the other flow path You may make it connect with the some gas hole of the edge part area | region of a board | substrate mounting surface. According to this, not only the focus ring but also the edge portion region of the substrate can be temperature controlled separately from the center portion region by the second heat transfer gas, so that the processing characteristics of the edge portion region of the substrate can be directly controlled.

  In order to solve the above-described problem, according to another aspect of the present invention, a substrate is disposed in a processing chamber, a focus ring is disposed so as to surround the periphery of the substrate, and the substrate is subjected to plasma processing. A substrate processing method for an apparatus, the substrate processing apparatus comprising: a mounting table having a substrate mounting surface on which the substrate is mounted; a susceptor having a focus ring mounting surface on which the focus ring is mounted; and the susceptor A susceptor temperature adjustment mechanism that adjusts the temperature of the substrate, a substrate holding unit that electrostatically attracts the back surface of the substrate to the substrate mounting surface, and electrostatically attracts the back surface of the focus ring to the focus ring mounting surface, A first heat transfer gas supply section for supplying a first heat transfer gas to the back surface of the substrate at a desired pressure; and a second heat transfer gas for supplying a second heat transfer gas to the back surface of the focus ring at a desired pressure. An in-plane treatment of the substrate by changing a supply pressure of the second heat transfer gas with respect to a supply pressure of the first heat transfer gas. There is provided a substrate processing method characterized by controlling characteristics.

  In order to solve the above-described problem, according to another aspect of the present invention, a substrate is disposed in a processing chamber, a focus ring is disposed so as to surround the periphery of the substrate, and the substrate is subjected to plasma processing. A substrate processing method for an apparatus, the substrate processing apparatus comprising: a mounting table having a substrate mounting surface on which the substrate is mounted; a susceptor having a focus ring mounting surface on which the focus ring is mounted; and the susceptor A susceptor temperature adjustment mechanism that adjusts the temperature of the substrate, a substrate holding unit that electrostatically attracts the back surface of the substrate to the substrate mounting surface, and electrostatically attracts the back surface of the focus ring to the focus ring mounting surface, A first heat transfer gas supply section for supplying a first heat transfer gas to the back surface of the substrate at a desired pressure; and a second heat transfer gas for supplying a second heat transfer gas to the back surface of the focus ring at a desired pressure. A heat transfer gas supply mechanism provided independently with a supply unit, and controlling in-plane processing characteristics of the substrate by changing a gas type of the first heat transfer gas and the second heat transfer gas. A substrate processing method is provided.

  According to the present invention, both the substrate and the focus ring are electrostatically adsorbed, and the heat transfer gas is supplied not only to the back surface of the substrate but also to the back surface of the focus ring, so that the heat with the temperature-controlled susceptor can be obtained. The conductivity can be changed independently, and the temperature of the focus ring can be controlled independently of the substrate temperature. Thereby, the in-plane processing characteristics of the substrate can be improved or freely controlled.

It is sectional drawing which shows the structural example of the substrate processing apparatus concerning embodiment of this invention. It is sectional drawing which shows the structural example of the heat transfer gas supply mechanism in the embodiment. It is the fragmentary sectional view which expanded the structure of the vicinity of the focus ring shown in FIG. FIG. 3B is a perspective view of the portion shown in FIG. 3A. It is a figure which shows the experimental result which made the graph the relationship between the heat-transfer gas pressure and the etching rate in a wafer surface in the embodiment. It is a figure which shows the specific example of the process sequence in the embodiment. It is a figure which shows the other specific example of the process sequence in the embodiment. It is a fragmentary sectional view which shows the modification of the distribution structure of the 2nd heat transfer gas in a focus ring mounting surface. It is a perspective view which shows the part except the focus ring shown to FIG. 7A. It is a fragmentary sectional view which shows the other modification of the distribution structure of the 2nd heat transfer gas in a focus ring mounting surface. It is a fragmentary sectional view which shows the case where a groove part is provided in the modification shown to FIG. 8A. It is a fragmentary sectional view which shows the other modification of the distribution structure of the 2nd heat transfer gas in a focus ring mounting surface, and is a case where a seal part is provided in both the inner peripheral side and outer peripheral side of a focus ring. FIG. 9B is a partial cross-sectional view when a seal portion is provided only on the inner peripheral side of the focus ring in the modification shown in FIG. 9A. FIG. 9B is a partial cross-sectional view when a seal portion is provided only on the outer peripheral side of the focus ring in the modification shown in FIG. 9A. FIG. 9B is a partial cross-sectional view in a case where seal portions are not provided on both the inner and outer peripheral sides of the focus ring in the modification shown in FIG. 9A. FIG. 5 is a partial cross-sectional view conceptually showing a case where the porosity of the focus ring mounting surface is made larger than the porosity of the substrate mounting surface in the thermal spray coating constituting the surface of the electrostatic chuck. FIG. 5 is a partial cross-sectional view conceptually showing a case where the porosity of the focus ring mounting surface is made smaller than the porosity of the substrate mounting surface in the sprayed coating constituting the surface of the electrostatic chuck. It is the fragmentary sectional view which showed notionally the case where the sprayed coating which comprises the surface of an electrostatic chuck made two layers of the sprayed coating of a focus ring mounting surface. It is sectional drawing which shows the other structural example of the heat transfer gas supply mechanism in the embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

(Substrate processing equipment)
First, a schematic configuration of a substrate processing apparatus according to an embodiment of the present invention will be described with reference to the drawings. Here, a case where the substrate processing apparatus is constituted by a parallel plate type plasma processing apparatus will be described as an example. FIG. 1 is a longitudinal sectional view showing a schematic configuration of a substrate processing apparatus 100 according to the present embodiment.

  The substrate processing apparatus 100 includes a processing chamber 102 having a processing container formed into a cylindrical shape made of aluminum whose surface is anodized (anodized), for example. The processing chamber 102 is grounded. A substantially cylindrical mounting table 110 for mounting the wafer W is provided at the bottom of the processing chamber 102. The mounting table 110 includes a plate-like insulator 112 made of ceramic or the like, and a susceptor 114 constituting a lower electrode provided on the insulator 112.

  The mounting table 110 includes a susceptor temperature adjusting unit 117 that can adjust the susceptor 114 to a predetermined temperature. The susceptor temperature adjustment unit 117 is configured to circulate the temperature adjustment medium in an annular temperature adjustment medium chamber 118 provided in the susceptor 114 along the circumferential direction, for example.

  Above the susceptor 114, an electrostatic chuck 120 is provided as a substrate holding unit capable of attracting both the wafer W and the focus ring 124 disposed so as to surround the wafer W. A convex substrate mounting portion is formed at the upper center portion of the electrostatic chuck 120, and the upper surface of the substrate mounting portion constitutes a substrate mounting surface 115 on which the wafer W is mounted, and a lower portion around the substrate mounting surface 115 This upper surface constitutes a focus ring placement surface 116 on which the focus ring 124 is placed.

  The electrostatic chuck 120 has a configuration in which an electrode 122 is interposed between insulating materials. In the electrostatic chuck 120 according to the present embodiment, the electrode 122 extends not only below the substrate placement surface 115 but also below the focus ring placement surface 116 so that both the wafer W and the focus ring 124 can be attracted. It is provided.

  The electrostatic chuck 120 is applied with a predetermined DC voltage (for example, 1.5 kV) from a DC power source 123 connected to the electrode 122. As a result, the wafer W and the focus ring 124 are electrostatically attracted to the electrostatic chuck 120. For example, as shown in FIG. 1, the substrate mounting portion is formed to have a diameter smaller than the diameter of the wafer W, and the edge portion of the wafer W protrudes from the substrate mounting portion when the wafer W is mounted.

The mounting table 110 according to the present embodiment is provided with a heat transfer gas supply mechanism 200 that supplies heat transfer gas separately to the back surface of the wafer W and the back surface of the focus ring 124. Examples of such heat transfer gas include He gas that can efficiently cool the susceptor 114 with the cooling temperature of the wafer W and the focus ring 124 that receive plasma heat input through the electrostatic chuck 120, Ar gas, H _Two gases are also applicable.

  The heat transfer gas supply mechanism 200 is placed on the first heat transfer gas supply unit 210 that supplies the first heat transfer gas to the back surface of the wafer W placed on the substrate placement surface 115 and the focus ring placement surface 116. And a second heat transfer gas supply unit 220 for supplying a second heat transfer gas to the back surface of the focus ring 124.

  Via these heat transfer gases, the thermal conductivity between the susceptor 114 and the wafer W and the thermal conductivity between the susceptor 114 and the focus ring 124 can be controlled separately. For example, the pressure and gas type of the first heat transfer gas and the second heat transfer gas can be changed. Thereby, even if heat is input from the plasma, the in-plane uniformity of the wafer W can be improved, and a positive temperature difference is made between the temperature of the wafer W and the temperature of the focus ring 124. The in-plane processing characteristics of the wafer W can also be controlled. Specific configurations of the first heat transfer gas supply unit 210 and the second heat transfer gas supply unit 220 will be described later.

  An upper electrode 130 is provided above the susceptor 114 so as to face the susceptor 114. A space formed between the upper electrode 130 and the susceptor 114 becomes a plasma generation space. The upper electrode 130 is supported on the upper part of the processing chamber 102 via an insulating shielding member 131.

  The upper electrode 130 is mainly composed of an electrode plate 132 and an electrode support 134 that detachably supports the electrode plate 132. The electrode plate 132 is made of, for example, a silicon member, and the electrode support 134 is made of, for example, a conductive member such as aluminum whose surface is anodized.

  The electrode support 134 is provided with a processing gas supply unit 140 for introducing the processing gas from the processing gas supply source 142 into the processing chamber 102. The processing gas supply source 142 is connected to the gas inlet 143 of the electrode support 134 via a gas supply pipe 144.

For example, as shown in FIG. 1, the gas supply pipe 144 is provided with a mass flow controller (MFC) 146 and an opening / closing valve 148 in order from the upstream side. Note that an FCS (Flow Control System) may be provided instead of the MFC. From the processing gas supply source 142, as a processing gas for etching, for example, a fluorocarbon gas (C _x F _y ) such as C ₄ F ₈ gas is supplied.

The processing gas supply source 142 supplies, for example, an etching gas for plasma etching. 1 shows only one processing gas supply system including the gas supply pipe 144, the opening / closing valve 148, the mass flow controller 146, the processing gas supply source 142, etc., the substrate processing apparatus 100 includes a plurality of processing gases. A supply system is provided. For example, etching gases such as CF ₄ , O ₂ , N ₂ , and CHF ₃ are independently controlled in flow rate and supplied into the processing chamber 102.

  The electrode support 134 is provided with a substantially cylindrical gas diffusion chamber 135, for example, so that the processing gas introduced from the gas supply pipe 144 can be evenly diffused. A number of gas discharge holes 136 through which the processing gas from the gas diffusion chamber 135 is discharged into the processing chamber 102 are formed in the bottom of the electrode support 134 and the electrode plate 132. The processing gas diffused in the gas diffusion chamber 135 can be discharged uniformly from the large number of gas discharge holes 136 toward the plasma generation space. In this respect, the upper electrode 130 functions as a shower head for supplying a processing gas.

  Although not shown, the mounting table 110 is provided with a lifter that lifts the wafer W with lifter pins and removes it from the substrate mounting surface 115 of the electrostatic chuck 120.

  An exhaust pipe 104 is connected to the bottom of the processing chamber 102, and an exhaust part 105 is connected to the exhaust pipe 104. The exhaust unit 105 includes a vacuum pump such as a turbo molecular pump, and adjusts the inside of the processing chamber 102 to a predetermined reduced pressure atmosphere. In addition, a wafer W loading / unloading port 106 is provided on the side wall of the processing chamber 102, and a gate valve 108 is provided at the loading / unloading port 106. When carrying in / out the wafer W, the gate valve 108 is opened. Then, the wafer W is loaded / unloaded through the loading / unloading port 106 by a transfer arm or the like (not shown).

  A power supply device 150 that supplies two-frequency superimposed power is connected to the susceptor 114 constituting the lower electrode. The power supply device 150 includes a first high-frequency power supply mechanism 152 that supplies a first high-frequency power (plasma generation high-frequency power) having a first frequency, and a second high-frequency power (bias voltage) that is lower than the first frequency. The second high-frequency power supply mechanism 162 for supplying the high-frequency power for generation) is configured.

  The first high-frequency power supply mechanism 152 includes a first filter 154, a first matching unit 156, and a first power source 158 that are sequentially connected from the susceptor 114 side. The first filter 154 prevents the power component of the second frequency from entering the first matching unit 156 side. The first matching unit 156 matches the first high-frequency power component.

  The second high-frequency power supply mechanism 162 includes a second filter 164, a second matching unit 166, and a second power source 168 that are sequentially connected from the susceptor 114 side. The second filter 164 prevents the power component of the first frequency from entering the second matching unit 166 side. The second matching unit 166 matches the second high frequency power component.

  A control unit (overall control device) 170 is connected to the substrate processing apparatus 100, and each unit of the substrate processing apparatus 100 is controlled by the control unit 170. Further, the control unit 170 includes a keyboard for an operator to input commands for managing the substrate processing apparatus 100, a display for visualizing and displaying the operation status of the substrate processing apparatus 100, and an input operation terminal function. An operation unit 172 including a touch panel having both state display functions is connected.

  Further, the control unit 170 includes a program for realizing various processes (such as plasma processing for the wafer W) executed by the substrate processing apparatus 100 under the control of the control unit 170 and processing conditions necessary for executing the program. A storage unit 174 that stores (recipe) and the like is connected.

  For example, a plurality of processing conditions (recipes) are stored in the storage unit 174. Each processing condition is a collection of a plurality of parameter values such as control parameters and setting parameters for controlling each part of the substrate processing apparatus 100. Each processing condition has parameter values such as a processing gas flow rate ratio, processing chamber pressure, and high-frequency power.

  Note that these programs and processing conditions may be stored in a hard disk or semiconductor memory, or are stored in a storage medium that can be read by a portable computer such as a CD-ROM or DVD, in the storage unit 174. You may set it to a position.

  The control unit 170 executes a desired process in the substrate processing apparatus 100 by reading out a desired program and processing conditions from the storage unit 174 based on an instruction from the operation unit 172 and controlling each unit. Further, the processing condition can be edited by an operation from the operation unit 172.

  In the substrate processing apparatus 100 having such a configuration, when plasma processing is performed on the wafer W on the susceptor 114, a first high frequency (eg, 100 MHz) of 10 MHz or more is applied to the susceptor 114 from the first power source 158 with a predetermined power. In addition to the supply, a second high frequency (for example, 3 MHz) of 2 MHz or more and less than 10 MHz is supplied from the second power source 168 with a predetermined power. As a result, plasma of a processing gas is generated between the susceptor 114 and the upper electrode 130 by the action of the first high frequency, and a self-bias voltage (−Vdc) is generated in the susceptor 114 by the action of the second high frequency. The plasma treatment can be performed on. In this way, by supplying the first high frequency and the second high frequency to the susceptor 114 and superimposing them, it is possible to appropriately control the plasma and perform good plasma processing on the wafer W.

  By the way, when plasma is generated on the wafer W, not only the wafer W but also the focus ring 124 arranged around the wafer W is exposed to the plasma, and therefore receives heat input from the plasma. At this time, although the susceptor 114 is controlled to a predetermined temperature, the temperature of the focus ring 124 may vary depending on the thermal conductivity between the susceptor 114 and the focus ring 124. In particular, if the temperature of the focus ring 124 fluctuates, the in-plane processing characteristics of the wafer W will be affected.

  Therefore, in this embodiment, not only the temperature of the wafer W but also the focus ring is provided by providing the heat transfer gas supply mechanism 200 for supplying the heat transfer gas not only on the back surface of the wafer W but also on the back surface of the focus ring 124. The temperature variation of 124 is also prevented. Moreover, the heat transfer gas supply mechanism 200 includes a first heat transfer gas supply unit 210 that supplies the first heat transfer gas to the back surface of the wafer W, and a second heat transfer gas that supplies the second heat transfer gas to the back surface of the focus ring 124. By configuring the hot gas supply unit 220 in a separate system, the thermal conductivity between the susceptor 114 and the focus ring 124 can be controlled independently of the thermal conductivity between the susceptor 114 and the wafer W. In this way, by controlling the temperature of the focus ring 124, the in-plane processing characteristics of the wafer W can be improved or freely controlled.

(Heat transfer gas supply mechanism)
A configuration example of the heat transfer gas supply mechanism 200 in the present embodiment will be described in detail with reference to the drawings. 2 is a cross-sectional view for explaining a configuration example of the heat transfer gas supply mechanism 200. Components having the same functional configuration as those shown in FIG. 1 are denoted by the same reference numerals and detailed description thereof is omitted. To do.

  As shown in FIG. 2, the heat transfer gas supply mechanism 200 includes a first heat transfer gas supply unit 210 and a second heat transfer gas supply unit 220 provided in separate and independent systems. The first heat transfer gas supply unit 210 supplies the first heat transfer gas at a predetermined pressure via the first gas flow path 212 between the substrate mounting surface 115 of the electrostatic chuck 120 and the back surface of the wafer. It has become. Specifically, the first gas channel 212 penetrates through the insulator 112 and the susceptor 114 and communicates with a number of gas holes 218 provided in the substrate mounting surface 115. Here, the gas holes 218 are formed on almost the entire surface from the center portion (central portion) to the edge portion (peripheral portion) of the substrate mounting surface 115.

  A first heat transfer gas supply source 214 that supplies the first heat transfer gas is connected to the first gas flow path 212 via a pressure control valve (PCV) 216. The pressure control valve (PCV) 216 adjusts the flow rate so that the pressure of the first heat transfer gas becomes a predetermined pressure. In addition, the number of the 1st gas flow paths 212 which supply 1st heat transfer gas from the 1st heat transfer gas supply source 214 may be one or more.

  The second heat transfer gas supply unit 220 supplies the second heat transfer gas at a predetermined pressure via the second gas flow path 222 between the substrate mounting surface 115 of the electrostatic chuck 120 and the back surface of the focus ring 124. It comes to supply. Specifically, the second gas flow path 222 passes through the insulator 112 and the susceptor 114 and communicates with a number of gas holes 228 provided on the focus ring mounting surface 116. Here, the gas hole 218 is formed on almost the entire surface of the focus ring mounting surface 116.

  A second heat transfer gas supply source 224 that supplies the second heat transfer gas is connected to the second gas flow path 222 via a pressure control valve 226. The pressure control valve (PCV) 226 adjusts the flow rate so that the pressure of the second heat transfer gas becomes a predetermined pressure. The number of the second gas flow paths 222 for supplying the second heat transfer gas from the second heat transfer gas supply source 224 may be one or a plurality.

  The gas holes 228 provided in the focus ring mounting surface 116 are configured as shown in FIGS. 3A and 3B, for example. FIG. 3A is a cross-sectional view for explaining a configuration example of the gas hole 228 and is a partially enlarged view of the vicinity of the focus ring 124 of FIG. 3B is a perspective view showing a portion excluding the focus ring 124 shown in FIG. 3A. 3A and 3B, the illustration of the electrode 122 of the electrostatic chuck 120 is omitted.

  The configuration example shown in FIGS. 3A and 3B is a case where a first annular diffusion portion 229 made of an annular space along the circumferential direction of the focus ring 124 is provided inside the electrostatic chuck 120. The lower end of each gas hole 228 is communicated with the upper part of the first annular diffusion part 229, and the second gas flow path 222 is communicated with the lower part of the first annular diffusion part 229. According to this, the second heat transfer gas is supplied along the circumferential direction of the first annular diffusion portion 229 by supplying the second heat transfer gas to the first annular diffusion portion 229 via the second gas flow path 222. Thus, the gas can be ejected from the gas holes 228 while being diffused throughout, so that it can be distributed evenly over the entire back surface of the focus ring.

  As described above, the first heat transfer gas supply unit 210 that supplies the first heat transfer gas to the back surface of the wafer W, and the second heat transfer gas supply unit 220 that supplies the second heat transfer gas to the back surface of the focus ring 124. By using a separate system, the pressure of the heat transfer gas supplied to the back surface of the wafer and the back surface of the focus ring can be changed, or the gas type can be changed. Thereby, the thermal conductivity between the susceptor 114 and the focus ring 124 can be controlled independently of the thermal conductivity between the susceptor 114 and the wafer W. Thereby, the temperature of the focus ring 124 can be controlled, so that the in-plane processing characteristics of the wafer W (for example, the processing rate of the edge portion of the wafer W) can be controlled.

  Here, experimental results showing the relationship between the pressure of the second heat transfer gas and the in-plane processing characteristics of the wafer W will be described with reference to the drawings. FIG. 4 is a graph showing the results of this experiment. In this experiment, the first heat transfer gas and the second heat transfer gas are both He gas, and the second heat transfer gas is maintained at 10 Torr, while maintaining the first heat transfer gas at a constant pressure (40 Torr in this case). The same etching process was performed on the photoresist (PR) film on the wafer having a diameter of 300 mm while changing to 30 Torr and 50 Torr. FIG. 4 is a plot obtained by measuring the etching rates at a plurality of points from −150 mm to 150 mm with the center of the wafer W being zero. Other main processing conditions are as follows.

[Processing conditions]
Processing gas: C ₅ F ₈ gas, Ar gas, O ₂ gas Processing chamber pressure: 25 mTorr
First high frequency (60 MHz): 3300 W
Second high frequency (2 MHz): 3800 W
Susceptor temperature (lower electrode temperature): 20 ° C

  According to the experimental results shown in FIG. 4, the etching rate of the edge portion of the wafer W is higher when the second heat transfer gas is supplied to the back surface of the focus ring 124 at 30 Torr than when the second heat transfer gas is supplied at 10 Torr. Thus, it can be seen that the etching rate of the center portion of the wafer W has hardly changed. This is because the higher the pressure of the second heat transfer gas, the higher the thermal conductivity of the focus ring 124 due to the second heat transfer gas, and the temperature of the focus ring can be made lower than the temperature of the wafer W. Can be guessed. Further, as the pressure of the second heat transfer gas is increased, leakage to the vicinity of the outer periphery of the wafer W is likely to occur, and it can be inferred that this also influenced the etching rate of the edge portion.

  Further, it can be seen that when the pressure of the second heat transfer gas is increased and supplied at 50 Torr, not only the edge portion of the wafer W but also the etching rate of the center portion is increased. If the pressure of the second heat transfer gas is further increased, the heat conductivity of the focus ring 124 due to the second heat transfer gas is further increased, and the amount of leakage of the second heat transfer gas is further increased. Therefore, it can be assumed that the etching rate at the center was also affected.

  According to this, at least in the range of 10 Torr to 30 Torr, only the etching rate of the edge portion of the wafer W can be increased as the pressure of the second heat transfer gas is increased. Further, in the range exceeding at least 50 Torr, the etching rate of both the center portion and the edge portion of the wafer W can be increased as the pressure of the second heat transfer gas is increased.

  Next, a case where the control of the in-plane processing characteristics by the pressure of the heat transfer gas is applied to a specific processing of the wafer W will be described with reference to the drawings. FIG. 5 is a diagram showing a specific example of a process sequence when the wafer W is processed in a plurality of steps. Here, the case where the pressure of the heat transfer gas supplied to the back surface of the wafer and the back surface of the focus ring is changed according to the step will be described as an example.

  For example, as shown in FIG. 5, after a predetermined voltage is applied to the electrostatic chuck 120 from a DC power source 123 to electrostatically attract the wafer W placed on the substrate placement surface 115, the first step includes, for example, The first heat transfer gas is supplied at a predetermined pressure, and the second heat transfer gas is supplied at the same pressure to generate a processing gas plasma and process the wafer W.

  When the first step is completed, the supply of the first heat transfer gas and the second heat transfer gas is stopped, and the process proceeds to the second step. In the second step, for example, the first heat transfer gas is supplied at the same pressure as in the first step, and the second heat transfer gas is supplied at a lower pressure to generate plasma of the processing gas to etch the wafer W. Process the process. Thus, by adjusting the pressures of the first heat transfer gas and the second heat transfer gas independently for each step, the optimum in-plane processing characteristics of the wafer W can be obtained, and the surface of the wafer W can be obtained. The internal processing characteristics can be freely controlled.

  In addition, although FIG. 5 demonstrated the case where 1st heat transfer gas and 2nd heat transfer gas were supplied for every step, it is not restricted to this. For example, the second heat transfer gas may be continuously supplied in each step. FIG. 6 is a diagram showing another specific example of the process sequence, in which the first heat transfer gas is supplied at each step while the second heat transfer gas is supplied continuously at each step. It is.

  In this case, it is preferable to supply the second heat transfer gas while applying a predetermined voltage from the DC power source 123 to at least the electrostatic chuck 120 so that the wafer W is not displaced or cracked. In FIG. 6, the second heat transfer gas is supplied to the electrostatic chuck 120 at a timing at which a predetermined voltage is applied from the DC power supply 123, and at the timing at which the application of the predetermined voltage from the DC power supply 123 is stopped to the electrostatic chuck 120. A second heat transfer gas is supplied.

  Thus, the cooling efficiency is increased by continuously cooling the focus ring 124 over a plurality of steps, and the etching rate of the edge portion of the wafer W can be further increased.

  Up to this point, the case where the in-plane processing characteristics are controlled by changing the pressure of the first heat transfer gas and the second heat transfer gas has been described, but the gas type of the first heat transfer gas and the second heat transfer gas is changed. In this way, the in-plane processing characteristics of the wafer W can be controlled.

For example, while using He gas as the first heat transfer gas and using another inert gas such as Ar gas or N ₂ gas as the _second heat transfer gas, the cooling efficiency of the focus ring 124 is increased and the plasma density is increased. Can be controlled. In this case, since the amount of leak can be increased by increasing the pressure of the second heat transfer gas, the plasma density at the edge portion of the wafer W can be controlled. As a result, the processing rate of the edge portion relative to the center portion of the wafer W can be increased.

Further, the first heat transfer gas uses He gas and O ₂ gas as the second heat transfer gas, so that the pressure is increased as in the case of the inert gas, and the processing rate (for example, etching rate) of the edge portion is increased. Can be raised. O ₂ gas can remove reaction products (depots) generated by plasma processing (for example, etching processing), and thus can increase the processing rate (for example, etching rate).

In addition, He gas is used as the first heat transfer gas, and CF type (C ₅ F ₈ , C ₄ F ₆ , C ₃ F ₈ , C ₄ F ₈ etc.) gas, CHF type (as the second heat transfer gas) By using a gas such as CHF ₃ or CH ₂ F _2, the processing rate (for example, the etching rate) of the edge portion of the wafer W can be increased by increasing the pressure as in the case of the inert gas. Since CF-based gas and CHF-based gas can deposit reaction products (depots) generated by plasma processing (for example, etching processing), the processing rate (for example, etching rate) of the edge portion of the wafer W is lowered. Can do.

  As described above, the heat transfer gas supply mechanism 200 according to the present embodiment can supply the first heat transfer gas and the second heat transfer gas to the back surface of the wafer and the back surface of the focus ring, respectively. The pressure and gas type of the gas and the second heat transfer gas can also be changed. As a result, the heat conductivity between the susceptor 114 and the wafer W and the heat conductivity between the susceptor 114 and the focus ring 124 can be separately controlled via these heat transfer gases. Even if there is, fluctuations in the temperature of the focus ring 124 can be prevented, so that the in-plane uniformity of the wafer W can be improved. In addition, the in-plane processing characteristics of the wafer W can be freely controlled by positively creating a temperature difference between the temperature of the wafer W and the temperature of the focus ring 124.

  In the above embodiment, the case where a plurality of gas holes 228 are provided as shown in FIGS. 2, 3, and 4 is given as an example of the second heat transfer gas flow structure on the focus ring mounting surface 116. However, what is necessary is just to be able to supply the second heat transfer gas uniformly over the entire back surface of the focus ring 124, and is not limited to those shown in FIGS.

(Modification of the distribution structure of the second heat transfer gas)
Here, a modification of the flow structure of the second heat transfer gas on the focus ring mounting surface 116 will be described with reference to the drawings. FIG. 7A is a cross-sectional view for explaining a modified example of the flow structure of the second heat transfer gas, in which the vicinity of the focus ring 124 in this modified example is partially enlarged. FIG. 7B is a perspective view showing a portion excluding the focus ring 124 shown in FIG. 7A. 7A and 7B, the electrode 122 of the electrostatic chuck 120 is omitted.

  In the configuration example shown in FIGS. 7A and 7B, a second annular diffusing portion 232 including an annular recess is provided on the surface of the focus ring placement surface 116 along the circumferential direction of the focus ring 124. The second gas passage 222 is communicated with the second annular diffusion portion 232, and the second heat transfer gas is supplied to the second annular diffusion portion 232 via the second gas passage 222. As a result, the second heat transfer gas can be diffused along the circumferential direction in the entire second annular diffusion portion 232 directly below the back surface of the focus ring 124, and thus can be evenly distributed over the entire back surface of the focus ring.

  In addition, as shown in FIG. 8A, the second annular diffusion portion 232 may be provided with a plurality of protrusions 233 to support the focus ring 124. According to this, the plurality of protrusions 233 can be brought into direct contact with the back surface of the focus ring 124 for heat transfer. Thereby, the part which contacts the back surface of the focus ring 124 and transfers heat can be increased.

  In this case, as shown in FIG. 8B, a groove portion 238 along the circumferential direction may be provided at the lower portion of the second annular diffusion portion 232, and the second gas flow path 222 may be communicated with the groove portion 238. . According to this, even when the number of protrusions 233 of the second annular diffusion part 232 is large and difficult to diffuse, the second heat transfer gas from the second gas flow path 222 diffuses in the circumferential direction via the groove part 238. As a result, the entire second annular diffusion portion 232 is easily spread. In this case, by making the groove width of the groove 238 larger than the hole diameter of the gas flow path 222, the second heat transfer gas entering the groove 238 from the gas flow path 222 can be diffused more efficiently.

  In addition to the above, by increasing the surface roughness of the focus ring mounting surface 116, the second heat transfer gas from the second gas flow path 222 can be caused to pass through the rough surface of the focus ring mounting surface 116 (the uneven surface). Can be diffused over the circumferential direction of the focus ring 124. Specifically, for example, as shown in FIG. 9A, a portion whose surface roughness is roughened to the extent that the second heat transfer gas flows on the focus ring mounting surface 116 is formed along the circumferential direction of the focus ring 124. And the 2nd gas flow path 222 is connected to the site | part which roughened this surface roughness.

  In this case, as shown in FIG. 9A, seal portions 240 for sealing the second heat transfer gas may be provided on both the inner peripheral side and the outer peripheral side of the focus ring mounting surface 116. Accordingly, the second heat transfer gas can be made difficult to leak from the inner peripheral side and the outer peripheral side of the focus ring mounting surface 116 as compared with the case where there is no such seal portion 240. Thereby, the processing characteristics of the edge portion of the wafer W can be controlled by enhancing the heat transfer effect of the focus ring 124 by the second heat transfer gas itself.

  The seal portion 240 is not provided on both or one of the inner peripheral side and the outer peripheral side of the focus ring mounting surface 116, so that the second heat transfer gas is supplied from both or one of the inner peripheral side and the outer peripheral side. May be actively leaked. According to this, not only the heat transfer effect by the second heat transfer gas itself, but also the second heat transfer gas can be leaked in the vicinity of the edge portion of the wafer W, so that the ratio of the gas components in the vicinity of the edge portion is set. The processing characteristics of the edge portion of the wafer W can also be controlled by changing it.

  In FIG. 9B, the seal portion 240 is provided only on the inner peripheral side of the focus ring mounting surface 116, so that the second heat transfer gas is easily leaked from the outer peripheral side. Conversely, in FIG. 9C, the seal portion 240 is provided only on the outer peripheral side of the focus ring mounting surface 116, so that the second heat transfer gas is easily leaked from the inner peripheral side. In FIG. 9D, the seal portion 240 is not provided on both the inner peripheral side and the outer peripheral side of the focus ring mounting surface 116, so that the second heat transfer gas is easily leaked from both the inner peripheral side and the outer peripheral side. .

  Further, a groove 238 similar to that shown in FIG. 8B may be provided on the focus ring mounting surface 116 shown in FIGS. 9A to 9D, and the second gas flow path 222 may be communicated with the groove 238. According to this, the second heat transfer gas from the second gas flow path 222 diffuses in the circumferential direction through the groove portion 238 regardless of the degree of surface roughness of the focus ring mounting surface 116, and thus the focus ring mounting surface 116. It becomes easy to reach the entire placement surface 116. Also in this case, the second heat transfer gas entering the groove 238 from the gas flow path 222 can be more efficiently diffused by making the groove width of the groove 238 larger than the hole diameter of the gas flow path 222 as in the case shown in FIG. 8B. Can be made.

  9A to 9C may be applied to the surface structure of the focus ring mounting surface 116 provided with the projection 233 as shown in FIG. 8A. Further, in the surface structure of the focus ring mounting surface 116 shown in FIG. 8A, the seal portion 240 may not be provided on both the inner peripheral side and the outer peripheral side.

(Electrostatic chuck surface processing)
Next, surface processing of the electrostatic chuck 120 will be described. On the surface of the electrostatic chuck 120, a sprayed coating such as Al ₂ O ₃ or Y ₂ O ₃ is formed by spraying (see, for example, sprayed coatings 115A and 116A shown in FIG. 10A described later). In this case, the heat conduction from the focus ring mounting surface 116 to the focus ring 124 is changed by changing the porosity of the spray coating 116A on the focus ring mounting surface 116 with respect to the porosity of the spray coating 115A on the substrate mounting surface 115. Since the rate can be changed, the temperature of the focus ring 124 can also be controlled by this.

  Here, the amount of heat from the plasma is Q, the area of the focus ring mounting surface 116 is S, the thickness of the thermal spray coating is L, and the temperature difference between the upper surface of the thermal spray coating 116A (the surface of the focus ring mounting surface 116) and the lower surface is dT. Then, since the thermal conductivity k is expressed by the following equation (1), the temperature difference dT between the upper surface and the lower surface of the thermal spray coating can be expressed by the following equation (2) from the following equation (1).

  k [W / cmK] = (Q · S) / (dT · L) (1)

  dT = (Q · S) / (k · L) (2)

  According to the above equation (2), the temperature of the surface of the focus ring mounting surface 116 (the upper surface of the sprayed coating 116A) increases as the porosity of the sprayed coating 116A increases and the thermal conductivity k decreases. The temperature of the focus ring 124 can be controlled in a relatively high temperature range. On the other hand, as the porosity of the thermal spray coating 116A is decreased and the thermal conductivity k is increased, the temperature of the surface of the focus ring mounting surface 116 (the upper surface of the thermal spray coating 116A) is decreased. The focus ring 124 can be controlled within a range.

  Here, a specific example in which the porosity of the spray coating 116A on the focus ring mounting surface 116 is changed will be described with reference to the drawings. FIG. 10A is a partial cross-sectional view when the porosity of the thermal spray coating 116A on the focus ring mounting surface 116 is larger than the porosity of the thermal spray coating 115A on the substrate mounting surface 115, and FIG. 10B is the focus ring mounting surface 116. It is a fragmentary sectional view at the time of making the porosity of 116A of this thermal spray coating smaller than the porosity of the thermal spray coating 115A of the board | substrate mounting surface 115. 10A and 10B conceptually show the difference in porosity between the thermal spray coatings 115A and 116A. 10A and 10B, the illustration of the configuration of the heat transfer gas supply mechanism 200 and the electrode 122 of the electrostatic chuck 120 is omitted.

  As shown in FIG. 10A, if the porosity of the thermal spray coating 116A on the focus ring mounting surface 116 is larger than the porosity of the thermal spray coating 115A on the substrate mounting surface 115, the thermal conductivity of the focus ring mounting surface 116 is increased. Will be lower. For example, when the porosity of the thermal spray coating on the substrate mounting surface 115 is 5%, the porosity of the thermal spray coating 116A on the focus ring mounting surface 116 is 8%. Accordingly, the focus ring 124 has a lower cooling effect by the second heat transfer gas with respect to the temperature rise due to plasma heat input than the wafer W, and controls the temperature of the focus ring 124 in a relatively high temperature range (for example, 100 ° C. or more). be able to.

  On the other hand, if the porosity of the sprayed coating 116A on the focus ring mounting surface 116 is smaller than that of the substrate mounting surface 115 as shown in FIG. 10B, the thermal conductivity of the focus ring mounting surface 116 is higher. Become. For example, when the porosity of the sprayed coating 115A on the substrate mounting surface 115 is 5%, the porosity of the sprayed coating 116A on the focus ring mounting surface 116 is 2%. As a result, the focus ring 124 has a higher cooling effect by the second heat transfer gas with respect to the temperature rise due to plasma heat input than the wafer W, and the temperature of the focus ring 124 can be controlled in a relatively low temperature range (for example, 0 ° C. to 20 ° C.). Can be controlled.

  Further, heat transfer from the focus ring mounting surface 116 to the focus ring 124 includes heat transfer from a portion in contact with the thermal spray coating 116A and heat transfer from a portion in contact with the heat transfer gas (for example, He gas). . The greater the porosity of the sprayed coating 116A, the higher the contribution from heat transfer from the portion in contact with the heat transfer gas. On the other hand, the smaller the porosity of the sprayed coating 116A, the higher the contribution by heat transfer from the portion in contact with the sprayed coating 116A. Therefore, by changing the porosity of the thermal spray coating 116A as necessary, the contribution ratio of the heat transfer from the thermal spray coating 116A and the heat transfer from the heat transfer gas can be changed. This also increases the temperature control efficiency (for example, cooling efficiency) of the focus ring 124.

  10A and 10B illustrate the case where the spray coating 116A on the focus ring mounting surface 116 is a single layer, but the present invention is not limited to this, and a plurality of spray coatings 116A on the focus ring mounting surface 116 are provided. You may make it change the porosity of each layer as a layer. For example, FIG. 10C shows a partial cross-sectional view when the spray coating 116A on the focus ring mounting surface 116 is formed in two layers. FIG. 10C conceptually shows the difference in porosity of each layer.

  Specifically, FIG. 10C shows a case where the thermal spray coating 116A on the focus ring mounting surface 116 is composed of two layers of an upper thermal spray coating 116a and a lower thermal spray coating 116b. The porosity of the entire sprayed coating 116A may be changed by changing the porosity of the sprayed coatings 116a and 116b of these layers. In this case, the sprayed coatings 116a and 116b of each layer may be made of the same material or different materials.

For example, the lower layer sprayed coating 116b is formed of a PSZ (partially stabilized zirconia) sprayed coating, and an Al ₂ O ₃ or Y ₂ O ₃ sprayed coating is formed thereon. The sprayed coating 116a may be used. Also by this, the porosity of the whole sprayed coating 116A can be changed. For example, if the porosity of the PSZ layer, which is the lower spray coating 116b, is increased, the porosity of the entire spray coating 116A can be increased simply by forming the upper spray coating 116a of Al ₂ O ₃ or Y ₂ O ₃ as it is. it can. According to this, the process for changing the porosity of the upper sprayed coating 116a of Al ₂ O ₃ or Y ₂ O ₃ can be omitted, and the porosity of the entire sprayed coating 116A can be increased relatively easily.

(Other structural examples of heat transfer gas supply mechanism)
Next, another configuration example of the heat transfer gas supply mechanism 200 will be described with reference to the drawings. FIG. 11 is a cross-sectional view showing another configuration example of the heat transfer gas supply mechanism 200 in the present embodiment. In the configuration example of the heat transfer gas supply mechanism 200 shown in FIG. 2 described above, the case where the second heat transfer gas is configured to be supplied only to the back surface of the focus ring 124 has been described. An example will be given in which the supply is performed not only on the back surface of the focus ring 124 but also on the back surface of the edge portion of the wafer W.

  Specifically, for example, as shown in FIG. 11, the second gas flow path 222 may be branched and the branch flow path 223 may be provided toward the back surface of the edge portion of the wafer W. In this case, the gas holes 218 in the substrate mounting surface 115 are divided into a gas hole 218a in the center region and a gas hole 218b in the peripheral edge region, and the first gas flow is provided in the gas hole 218a in the center region. The channel 212 is communicated, and the branch channel 223 from the second gas channel 222 is communicated with the gas hole 218b in the edge region. As a result, the first heat transfer gas is supplied to the gas hole 218a in the center region, and the second heat transfer gas is supplied to the gas hole 218b in the edge region.

  According to the configuration shown in FIG. 11, not only the focus ring 124 but also the edge region of the wafer W can be controlled by the second heat transfer gas separately from the center region. Processing characteristics can be directly controlled.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the above-described embodiment, the substrate processing apparatus is described as an example of a substrate processing apparatus that generates plasma by superimposing and applying two types of high-frequency power only to the lower electrode, but the present invention is not limited to this. Instead, the substrate processing apparatus may be applied to another type, for example, a type in which only one type of high frequency power is applied to the lower electrode or a type in which two types of high frequency power are applied to the upper electrode and the lower electrode, respectively.

  The present invention is applicable to a substrate processing apparatus and a substrate processing method for performing plasma processing on a substrate such as a semiconductor wafer.

DESCRIPTION OF SYMBOLS 100 Substrate processing apparatus 102 Processing chamber 104 Exhaust pipe 105 Exhaust part 106 Unloading / inlet port 108 Gate valve 110 Mounting base 112 Insulator 114 Susceptor 115 Substrate mounting surface 115A Thermal spray coating 116 Focus ring mounting surface 116A Thermal spray coating 116a Upper thermal spray coating 116b Lower layer Thermal spray coating 117 Susceptor temperature control unit 118 Temperature control medium chamber 120 Electrostatic chuck 122 Electrode 123 DC power supply 124 Focus ring 130 Upper electrode 131 Insulating shielding member 132 Electrode plate 134 Electrode support 135 Gas diffusion chamber 136 Gas discharge hole 140 Processing gas Supply unit 142 Processing gas supply source 143 Gas introduction port 144 Gas supply pipe 146 Mass flow controller (MFC)
148 On-off valve 150 Power supply device 152 First high-frequency power supply mechanism 154 First filter 156 First matcher 158 First power supply 162 Second high-frequency power supply mechanism 164 Second filter 166 Second matcher 168 Second power supply 170 Control unit 172 Operation unit 174 Storage unit 200 Heat transfer gas supply mechanism 210 First heat transfer gas supply unit 212 First gas flow path 214 First heat transfer gas supply source 216 Pressure control valve (PCV)
218, 218a, 218b Gas hole 220 Second heat transfer gas supply unit 222 Second gas flow path 223 Branch flow path 224 Second heat transfer gas supply source 226 Pressure control valve (PCV)
228 Gas hole 229 First annular diffusion portion 232 Second annular diffusion portion 233 Projection portion 238 Groove portion 240 Seal portion W Wafer

Claims (4)

A substrate processing apparatus for disposing a substrate in a processing chamber, disposing a focus ring so as to surround the substrate, and performing plasma processing on the substrate,
A mounting table including a susceptor having a substrate mounting surface for mounting the substrate and a focus ring mounting surface for mounting the focus ring;
A susceptor temperature adjustment mechanism for adjusting the temperature of the susceptor;
A substrate holding unit that electrostatically attracts the back surface of the substrate to the substrate mounting surface and electrostatically attracts the back surface of the focus ring to the focus ring mounting surface;
A first heat transfer gas supply unit that supplies a first heat transfer gas to the back surface of the substrate and a second heat transfer gas supply unit that supplies a second heat transfer gas to the back surface of the focus ring are provided independently. A heat transfer gas supply mechanism,
A sprayed coating is formed on the surface of the focus ring mounting surface and the surface of the substrate mounting surface, and the porosity of the sprayed coating on the focus ring mounting surface with respect to the porosity of the sprayed coating on the substrate mounting surface. The substrate processing apparatus is characterized in that the in-plane processing characteristics of the substrate are controlled by changing. The substrate processing apparatus according to claim 1, wherein the porosity of the spray coating on the focus ring mounting surface is determined according to a control temperature range of the susceptor. A substrate processing method for a substrate processing apparatus in which a substrate is disposed in a processing chamber, a focus ring is disposed so as to surround the substrate, and plasma processing is performed on the substrate,
The substrate processing apparatus includes:
A mounting table including a susceptor having a substrate mounting surface for mounting the substrate and a focus ring mounting surface for mounting the focus ring;
A susceptor temperature adjustment mechanism for adjusting the temperature of the susceptor;
A substrate holding unit that electrostatically attracts the back surface of the substrate to the substrate mounting surface and electrostatically attracts the back surface of the focus ring to the focus ring mounting surface;
A first heat transfer gas supply unit that supplies a first heat transfer gas to the back surface of the substrate at a desired pressure, and a second heat transfer gas supply that supplies a second heat transfer gas to the back surface of the focus ring at a desired pressure. A heat transfer gas supply mechanism provided independently with the section,
A sprayed coating is formed on the surface of the focus ring mounting surface and the surface of the substrate mounting surface, and the porosity of the sprayed coating on the focus ring mounting surface with respect to the porosity of the sprayed coating on the substrate mounting surface. By controlling the rate, the in-plane processing characteristics of the substrate are controlled,
An in-plane processing characteristic of the substrate is further controlled by changing a supply pressure of the second heat transfer gas with respect to a supply pressure of the first heat transfer gas. A substrate processing method for a substrate processing apparatus in which a substrate is disposed in a processing chamber, a focus ring is disposed so as to surround the substrate, and plasma processing is performed on the substrate,
The substrate processing apparatus includes:
A mounting table including a susceptor having a substrate mounting surface for mounting the substrate and a focus ring mounting surface for mounting the focus ring;
A susceptor temperature adjustment mechanism for adjusting the temperature of the susceptor;
A substrate holding unit that electrostatically attracts the back surface of the substrate to the substrate mounting surface and electrostatically attracts the back surface of the focus ring to the focus ring mounting surface;
A first heat transfer gas supply unit that supplies a first heat transfer gas to the back surface of the substrate at a desired pressure, and a second heat transfer gas supply that supplies a second heat transfer gas to the back surface of the focus ring at a desired pressure. A heat transfer gas supply mechanism provided independently with the section,
A sprayed coating is formed on the surface of the focus ring mounting surface and the surface of the substrate mounting surface, and the porosity of the sprayed coating on the focus ring mounting surface with respect to the porosity of the sprayed coating on the substrate mounting surface. By controlling the rate, the in-plane processing characteristics of the substrate are controlled,
An in-plane processing characteristic of the substrate is further controlled by changing a gas type of the first heat transfer gas and the second heat transfer gas.

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