TW201324673A - Electrostatic chuck for controlling temperature of carried substrate and plasma processing device - Google Patents

Abstract

The present invention provides an electrostatic chuck for controlling temperature of a carried substrate, which is applicable to a carried substrate in a plasma processing device. The electrostatic chuck includes a first temperature control area and a second temperature control area. The first temperature control area and the second temperature control area are distributed up and down, and characterized by arranging at least one heat resistant area in the first temperature control area. A heat resistant area memory is disposed in a heat resistant trough. In addition, a plasma processing device is further provided. By arranging different heat resistant areas at different temperature control area of the electrostatic chuck, for reducing, the present invention can reduce horizontal heat transmission of the electrostatic chuck and maximally and vertically transmit heat from the electrostatic chuck to a substrate placed on the electrostatic chuck, thereby further improving the working efficiency of the plasma processing device utilizing the electrostatic chuck provided by the present invention, as well as saving energy.

Description

Electrostatic chuck and plasma processing device for controlling the temperature of a loaded substrate

The present invention relates to a semiconductor processing apparatus, and more particularly to a plasma processing apparatus that performs plasma processing on a substrate to be loaded, and more particularly to an electrostatic chuck for fixing a processed object such as a substrate subjected to plasma processing, and the electrostatic chuck. Disk plasma processing apparatus.

In the manufacturing process of a semiconductor device, such as etching, deposition, oxidation, sputtering, etc., the substrate (wafer) is usually processed by plasma. Generally, as a plasma processing apparatus, as a method of generating plasma, it can be roughly classified into a method using a glow discharge or a high-frequency discharge, and a method using microwaves.

For example, in a plasma processing apparatus of a high-frequency discharge type, a substrate to be processed is placed on an electrostatic chuck that fixes a substrate to be processed by an electrostatic force. In the process of plasma-treating the substrate to be processed, the ceramics constituting the electrostatic chuck transfer heat to the substrate to be processed in the longitudinal direction, and the ceramic of the electrostatic chuck also dissipates heat in the lateral direction. From the viewpoint of the operation of the substrate to be processed, it is not necessary for the ceramic to transfer thermal energy in the lateral direction, which causes waste of thermal energy.

Therefore, a technical solution is needed to solve the problem of lateral transfer of thermal energy from the electrostatic chuck. In the prior art, there is a change in the thermal conductivity of an electrostatic chuck by changing the thickness of an electrostatic chuck or the like. For example, U.S. Patent No. 5,761,023 proposes to control the different positions of the electrostatic chuck to control the electrolyte of different thicknesses. Technical solution for electrostatic chuck surface temperature, but this solution simply adjusts the thickness of the electrostatic chuck Degree does not work very well.

In view of the defects in the prior art that the thermal transfer of the electrostatic chuck is not well solved, it is an object of the present invention to provide an electrostatic chuck and a plasma processing apparatus for controlling the temperature of the loaded substrate.

The present invention provides an electrostatic chuck for controlling the temperature of a loaded substrate, which is used to carry a substrate in a plasma processing apparatus, the electrostatic chuck includes an electrostatic electrode wrapped by an insulating material layer, and the first insulating layer is disposed above the electrostatic electrode. A second insulating layer is disposed under the electrostatic electrode, and the electrostatic chuck includes a first temperature control region and a second temperature control region, wherein at least one heat blocking region is disposed between the first temperature control region and the second temperature control region, at least One of the upper surface or the lower surface of the heat blocking zone has a heat-resistant groove, and the depth of the heat-resistant groove exceeds 30% of the thickness of the first insulating layer or the second insulating layer.

The present invention also provides a plasma processing apparatus for plasma-treating a substrate, the substrate being carried by an electrostatic chuck, wherein the electrostatic chuck is the electrostatic chuck described above.

The invention sets different heat-blocking zones to different temperature control zones of the electrostatic chuck, thereby reducing the lateral heat transfer of the electrostatic chuck, and realizing the electrostatic chuck to transfer heat to the substrate placed on the electrostatic chuck maximally and longitudinally. Thereby, the working efficiency of the plasma processing apparatus to which the electrostatic chuck provided by the present invention is applied is further improved, and energy is saved.

1 shows a schematic longitudinal cross-sectional view of a plasma processing apparatus according to the prior art. Those skilled in the art understand that in the prior art, the plasma processing apparatus generally includes, for example, a closed space from the inside. The processing chamber 100 including the vacuum chamber; the mounting table 2 disposed at the center of the bottom surface of the processing container 100; and the upper electrode 80 disposed above the mounting table 2 so as to face the mounting table 2.

The structure of the mounting table 2 generally includes a base 34 provided with a lower electrode 20, the lower electrode 20 is adapted to the upper electrode 80, and an electrostatic chuck for fixing the substrate (wafer) 30 is disposed above the base. 32. The lower electrode 20 is fixed to the susceptor 34, for example, via an insulating member. And the lower electrode 20 is connected to a radio frequency power source.

Further, the upper electrode 80 is formed in a hollow shape, and a plurality of gas supply holes for dispersing and supplying a processing gas into the processing container 100 are formed, for example, uniformly dispersed on the lower surface thereof. A gas introduction pipe is provided at the center of the upper surface of the upper electrode 80. The gas introduction pipe penetrates the center of the upper surface of the processing container 100 and is connected to the processing gas supply source 810 upstream. Preferably, the processing gas supply source 810 is capable of controlling the switching of the processing gas supply amount of the plasma processing apparatus, and increasing or decreasing.

By the above respective device configurations, a pair of parallel plate electrodes composed of the lower electrode 20 and the upper electrode 80 are formed in the processing container 100 of the plasma processing apparatus. After the inside of the processing container 100 is adjusted to a predetermined pressure, high-frequency electric power is supplied from the radio frequency power source by introducing the processing gas, the processing gas is plasmatized, and the high-frequency flows through the lower electrode 20 → the plasma → the upper electrode 80 → the processing container 100 Wall → substantially formed passage. By the action of the plasma processing apparatus, etching of the substrate (wafer) 30 carried on the electrostatic chuck 32 is performed by plasma.

Further, those skilled in the art understand that the above electrostatic chuck 32 is preferably in the shape of a disk (or referred to as a cylinder) and is placed in the same It is a disk-shaped lower electrode 20. Preferably, the electrostatic chuck 32 described hereinafter is also disk-shaped and will not be described herein.

Fig. 2 is a longitudinal sectional view showing an electrostatic chuck 32 for a plasma processing apparatus according to a second embodiment of the present invention. Specifically, the electrostatic chuck 32 has a cylindrical shape and is preferably composed of ceramic for carrying the substrate 30 in the plasma processing apparatus, and includes an electrostatic electrode 323 having a first upper portion of the electrostatic electrode 323 The insulating layer 324 has a second insulating layer 325 underneath, and the first insulating layer 324 and the second insulating layer 325 enclose the electrostatic electrode 323. More specifically, the electrostatic chuck 32 further includes a first temperature control zone 321 and a second temperature control zone 322, as shown in FIG. At least one heat blocking zone 11 is disposed between the first temperature control zone 321 and the second temperature control zone 322, and at least one heat blocking groove 111 is disposed on the heat blocking zone 11. Further, FIG. 2 shows a preferred embodiment of the present invention. Specifically, a heat blocking zone 11 is disposed between the first temperature control zone 321 and the second temperature control zone 322, and there are many heat blocking zones 11 The heat-resistant groove 111 is stripped, and as can be seen from the longitudinal sectional view shown in this embodiment, the longitudinal section of the heat-resistant groove 111 is an inverted triangle. In some variations of the embodiment, the heat-blocking zone 11 may be provided in plurality, and each of the plurality of heat-blocking zones 11 is provided with only one heat-blocking groove 111, or a plurality of heat-blocking zones 11 are provided. There are a plurality of heat blocking grooves 111. Those skilled in the art understand that these variations can be implemented in conjunction with the embodiment shown in FIG. 2, and thus are not described herein. More specifically, the heat blocking groove 111 is disposed on the upper surface or the lower surface of the heat blocking zone 11, that is, the heat blocking groove 111 is disposed on the outer surface of the first insulating layer 324 or the second insulating layer 325, and the depth of the heat blocking groove 111 More than 30% of the thickness of the first insulating layer or the second insulating layer, but the depth is smaller than the first insulating layer 324 or the second insulating layer 325 80% of the thickness will not be described here.

More specifically, according to the embodiment shown in FIG. 2, preferably, the first insulating layer 324 and the second insulating layer 325 are respectively provided with a heat blocking groove 111 and a heat blocking groove 121, and further, the heat blocking groove 111 and The heat-resisting tank 121 is vertically symmetrical along the center line of the horizontal surface of the electrostatic chuck 32. In some variations, those skilled in the art understand that the heat-resistant bath 111 and the heat-resistant bath 121 may be vertically staggered, and will not be described herein. . Further, in the embodiment, the heat-resistant bath 111 and the heat-resistant bath 121 are both centered on the center point of the electrostatic chuck 32 and have a closed circumference, and the plurality of heat-insulating grooves 111 are in the first insulating layer. 324 or a plurality of heat-resistant grooves 121 are evenly distributed on the second insulating layer 325, that is, the spacing between each of the heat-resistant grooves 111 or the heat-resistant grooves 121 is equal, and in other variations, The distribution of the heat-resisting grooves 111 on the first insulating layer 324 or the plurality of heat-insulating grooves 121 on the second insulating layer 325 may be uneven. For example, the spacing between the two heat-resistant grooves 111 is greater than the other two resistances. The spacing between the heat sinks is understood by those skilled in the art, and these variations can be implemented in conjunction with the embodiment shown in FIG. 2, and are not described herein.

Fig. 3 is a longitudinal sectional view showing an electrostatic chuck 32 for a plasma processing apparatus according to a third embodiment of the present invention. This embodiment can be understood as a variation of the embodiment shown in FIG. 2 above. In order to more clearly illustrate the specific shape and size of the heat-resistant groove 111 or the heat-resistant groove 121 in the heat-blocking zone 11, FIG. 3 separately shows A structural view of a heat-blocking zone 11, specifically, in the present embodiment, a longitudinal section of the heat-resistant groove 111 or the heat-resistant groove 121 is rectangular, preferably, the heat-resistant groove 111 and the heat-resistant groove 121 are along the electrostatic chuck. The level of 32 is symmetrical below the line. More specifically, in a preferred embodiment, the spacing between each of the heat-resistant grooves 111 is equal, which is The spacing between each of the heat-insulating grooves 121 is also equal, and the width of each heat-resistant groove 111 is also equal. The heat-resistant groove 111 and the heat-resistant groove 121 are evenly distributed on the first insulating layer 324 and the second insulating layer. Among the 325, as shown in Figure 3. In some variations, the spacing between each of the heat-resistant slots 111 is different, and the spacing between each of the heat-resistant slots 111 is different from the spacing between each of the heat-resistant slots 121, that is, at this time. The heat blocking groove 111 and the heat blocking groove 121 above and below the electrostatic chuck 32 are completely irregularly distributed. Further preferably, those skilled in the art understand that the width of each heat-insulating groove 111 is equal, that is, the width of one heat-resistant groove 111 is equal to the width of the other heat-blocking groove 111, and still more preferably, each The width of the heat-blocking groove 111 and each of the heat-blocking grooves 121 are also equal; in another embodiment, the width of each of the heat-insulating grooves 111 is different, for example, one of the heat-resistant grooves 111 has a width larger than the other one. Further, the width of the heat-resistant groove is further different, and the width of the heat-resistant groove 111 is different from the width of the heat-resistant groove 121, and the widths of the two are not regular. The embodiments and the modifications shown in FIG. 3 can be implemented by those skilled in the art in conjunction with the above embodiments, and are not described herein.

Fig. 4 is a longitudinal sectional view showing an electrostatic chuck 32 for a plasma processing apparatus according to a fourth embodiment of the present invention. This embodiment can be understood as a variation of the embodiment shown in FIG. 2. Specifically, in the embodiment, preferably, the heat-resistant groove 111 and the heat-resistant groove 121 have a trapezoidal cross section, and the heat-resistant groove 111 and The heat-resistant groove 121 is symmetrical along the horizontal center line of the electrostatic chuck 32, and the heat-resistant groove 111 and the heat-resistant groove 121 are evenly distributed among the first insulating layer 324 and the second insulating layer 325. Further, in some variations, the heat blocking groove 111 and the heat blocking groove 121 may be alternately arranged up and down. More specifically, in a preferred embodiment, more The shape and size of the heat-insulating grooves 111 are completely the same, and are the same as the heat-blocking grooves 121. In some variations, the sizes of the plurality of heat-resistant grooves 111 are different, for example, each heat-resistant groove The depth of 111 may be different, or the groove widths of the plurality of heat blocking grooves 111 may be different, or the spacing between each heat blocking groove 111 may be unequal. Further, in another variation, the heat-resistant groove 111 and the heat-resistant groove 121 are both trapezoidal, but the sizes or pitches of the two are different. The embodiments and the modifications shown in FIG. 4 can be implemented by those skilled in the art in conjunction with the above embodiments, and are not described herein.

Fig. 5 is a longitudinal sectional view showing an electrostatic chuck 32 for a plasma processing apparatus according to a fifth embodiment of the present invention. This embodiment can be understood as a variation of the embodiment shown in FIG. 2 . Specifically, in the embodiment, the heat-resistant groove 111 or the heat-resistant groove 121 has an inverted trapezoidal cross section, and the FIG. 3 or FIG. 4 The similar heat blocking groove 111 or the heat blocking groove 121 is symmetrical along the level center line of the electrostatic chuck 32. Preferably, the shape and size of the plurality of heat-insulating grooves 111 are completely the same, and the heat-resistant grooves 121 are also the same, and the heat-resistant grooves 111 and the heat-resistant grooves 121 are evenly distributed on the first insulating layer 324 and the second. Among the insulating layers 325. In some variations, the sizes of the plurality of heat-insulating grooves 111 are different. For example, the depth of each of the heat-resistant grooves 111 may be different, or the groove widths of the plurality of heat-resistant grooves 111 may be different, or The spacing between each of the heat-resistant grooves 111 may also be unequal. Further, in another variation, the heat-resistant groove 111 and the heat-resistant groove 121 are both inverted trapezoids, but the sizes or pitches of the two are different. The embodiment and the modification shown in FIG. 5 can be implemented by those skilled in the art in combination with the above embodiments, and details are not described herein.

Figure 6 shows a plasma according to a sixth embodiment of the present invention A longitudinal sectional view of the electrostatic chuck 32 for the processing apparatus. This embodiment can be understood as a variation of the embodiment described above with reference to FIG. 2. Specifically, in the embodiment, the heat-resistant groove 111 or the heat-resistant groove 121 has a fan-shaped cross section. Preferably, the heat-blocking groove 111 or the heat-resistant groove 121 is symmetrically along the level center line of the electrostatic chuck 32, and each The shape and size of each of the heat-resistant grooves 111 are the same, and the shape and size of each of the heat-resistant grooves 121 are also the same. At this time, the heat-resistant groove 111 and the heat-resistant groove 121 are evenly distributed on the first insulating layer 324 and the second insulation. In layer 325. In some variations, the fan-shaped arc of each heat-resistant groove 111 may be different, and the fan-shaped arc of each heat-blocking groove 121 may be different. Further, in another variation, the heat-resistant groove 111 and the heat-resistant groove 121 are both fan-shaped, but the sizes or pitches of the two are different. The embodiments and the modifications shown in FIG. 6 can be implemented by those skilled in the art in conjunction with the above embodiments, and are not described herein.

Fig. 7 is a longitudinal sectional view showing an electrostatic chuck 32 for a plasma processing apparatus according to a seventh embodiment of the present invention. This embodiment can be understood as a variation of the embodiment described above with reference to FIG. 2. Specifically, in the embodiment, the heat-resistant groove 111 has a rectangular cross section, and the heat-resistant groove 121 has a triangular cross section, and the heat-resistant groove 111 and the heat-resistant groove 121 have different shapes, and preferably, the heat-resistant groove 111 Or the heat-resistant groove 121 is also symmetrical along the horizontal center line of the electrostatic chuck 32, and the heat-resistant groove 111 and the heat-resistant groove 121 are evenly distributed among the first insulating layer 324 and the second insulating layer 325. More specifically, in a preferred embodiment, the shape and size of the plurality of heat-resistant grooves 111 are the same, and similarly, the shape and size of the plurality of heat-resistant grooves 121 are also the same. In the different variants, the size of each heat-resisting tank 111 may be different, and the size of each heat-blocking groove 121 may also be different. For example, the depth of the heat-blocking groove 111 may be different. Or the heat-resistant grooves 121 are triangular, and the angles thereof may also be different. Further, in some variations, the shape of each heat-resistant groove 111 may also be different, for example, from left to right. Rectangles, triangles, trapezoids, or other shapes are randomly arranged. Similarly, the shape of each heat-resistant groove 121 may be different in the variation. The embodiments and the modifications shown in FIG. 7 can be implemented by those skilled in the art in combination with the above embodiments, and are not described herein.

Further, according to the heat-dissipating groove 111 and the heat-resistant groove 121 in the embodiment shown in FIG. 2 to FIG. 7, the cross-sectional shape may be a triangle (as shown in FIG. 2), or may be other shapes such as a rectangle (eg, Figure 3), trapezoidal (as shown in Figure 4), inverted trapezoid (as shown in Figure 5), or fan-shaped (as shown in Figure 6), etc., and the shape of the heat-resistant groove 111 and the heat-resistant groove 121 can be The same (as shown in FIG. 2 to FIG. 6 ) may also be different (as shown in FIG. 7 ), and those skilled in the art understand that the variations of these embodiments may be combined with FIG. 2 to FIG. 6 . The embodiment shown is implemented and will not be described here.

Fig. 8 is a cross-sectional view showing an electrostatic chuck 32 for a plasma processing apparatus according to an eighth embodiment of the present invention. In order to explain the present invention more clearly, FIG. 8 shows a cross-sectional view of the electrostatic chuck 32 after the substrate 30 to be processed is removed. It can be seen from the present embodiment that, in view of the electrostatic chuck 32, the central region of the electrostatic chuck 32 is provided with a first temperature control region 321 and the peripheral region thereof is provided with a second temperature control region 322, and the first temperature control region 321 is A heat blocking zone 11 is disposed between the second temperature control zone 322, and the heat blocking zone 11 has a plurality of heat blocking grooves 111. More specifically, preferably, the first temperature control region 321 is a circle, the second temperature control region 322 is a ring, and the heat blocking groove 111 in the first heat blocking region 11 is basically The upper circumference of the electrostatic chuck 32 has a closed circumference, that is, a ring, and in the case where there are a plurality of heat-insulating grooves 111 in the heat-blocking region 11, the plurality of heat-resistant grooves 111 are preferably evenly distributed, and thus The heat-resistant grooves 111 should be a plurality of concentric circles of equal spacing. Similarly, those skilled in the art understand that in the bottom view corresponding to FIG. 8, the plurality of heat-resistant grooves 121 of the second heat-blocking region 12 are also preferably a plurality of concentric circles of equal pitch. Since the cross-sectional view of the upper surface of the electrostatic chuck 32 is preferably shown in the present embodiment, the case of the second heat-resistant region 12 cannot be seen, but those skilled in the art can refer to this with reference to the prior embodiments. It is understood that the portions related to the second heat-blocking zone 12 or the heat-resistant groove 121 are similar in the following, and are not described herein.

More specifically, according to the heat-resistant bath 111 described in the embodiment shown in FIG. 8 or the heat-resistant bath 121 not shown in FIG. 8 , those skilled in the art understand that the plurality of heat-resistant slots 111 or the heat-resistant slots 121 may be For the uneven concentric circles, that is, the plurality of heat-resistant grooves 111 or the heat-resistant grooves 121 are densely distributed in the first heat-blocking zone 11 or the second heat-blocking zone 12, and the edge regions are sparsely distributed, or a plurality of resistors. The heat sink 111 or the heat-resistant bath 121 is sparsely centered in the first heat-blocking zone 11 or the second heat-blocking zone 12, and the edge regions are densely distributed. The embodiments and the modifications shown in FIG. 8 can be implemented by those skilled in the art in conjunction with the above embodiments, and are not described herein.

According to the embodiment shown in FIGS. 2 to 8, further, the person skilled in the art understands that the present invention provides the first heat-blocking zone 11 and the heat-blocking resistance on the first temperature control zone 321 and the second temperature control zone 322. The groove 111 and the second heat-blocking zone 12 and the heat-blocking groove 121 reduce the ceramic area of the electrostatic chuck 32, thereby limiting the heat transfer on the electrostatic chuck 32, and avoiding unnecessary heat waste, so as to achieve the design purpose of the present invention. .

The specific embodiments of the present invention have been described above. It is to be understood that the invention is not limited to the specific embodiments described above, and various modifications and changes may be made by those skilled in the art without departing from the scope of the invention.

100‧‧‧Processing container

11‧‧‧Thermal zone

111‧‧‧Resistance tank

121‧‧‧Resistance tank

2‧‧‧ mounting table

20‧‧‧ lower electrode

30‧‧‧Substrate

32‧‧‧Electrostatic chuck

321‧‧‧First temperature control zone

322‧‧‧Second temperature control zone

323‧‧‧Electrostatic electrodes

324‧‧‧First insulation

325‧‧‧Second insulation

34‧‧‧Base

80‧‧‧ upper electrode

810‧‧‧Processing gas supply

Other features, objects, and advantages of the present invention will become more apparent from the detailed description of the accompanying drawings < 2 is a longitudinal cross-sectional view showing an electrostatic chuck for a plasma processing apparatus according to a second embodiment of the present invention; and FIG. 3 is a view showing a plasma processing apparatus according to a third embodiment of the present invention. Longitudinal sectional view of an electrostatic chuck; Fig. 4 is a longitudinal sectional view showing an electrostatic chuck for a plasma processing apparatus according to a fourth embodiment of the present invention; and Fig. 5 is a view showing a plasma according to a fifth embodiment of the present invention. 6 is a longitudinal sectional view of an electrostatic chuck for a processing apparatus; FIG. 6 is a longitudinal sectional view showing an electrostatic chuck for a plasma processing apparatus according to a sixth embodiment of the present invention; and FIG. 7 shows a seventh embodiment according to the present invention. Longitudinal sectional view of an electrostatic chuck for a plasma processing apparatus; and FIG. 8 shows a cross section of an electrostatic chuck for a plasma processing apparatus according to an eighth embodiment of the present invention .

11‧‧‧Thermal zone

111‧‧‧Resistance tank

121‧‧‧Resistance tank

32‧‧‧Electrostatic chuck

321‧‧‧First temperature control zone

322‧‧‧Second temperature control zone

323‧‧‧Electrostatic electrodes

324‧‧‧First insulation

325‧‧‧Second insulation

Claims (9)

An electrostatic chuck for controlling a temperature of a loaded substrate, the substrate for carrying a substrate in a plasma processing apparatus, the electrostatic chuck comprising an electrostatic electrode wrapped by a layer of insulating material, the electrostatic electrode comprising a first insulating layer thereon, A second insulating layer is disposed under the electrostatic electrode, the electrostatic chuck includes a first temperature control region and a second temperature control region, wherein at least one heat blocking region is disposed between the first temperature control region and the second temperature control region (11) At least one of the upper surface or the lower surface of the heat blocking zone (11) has a heat-resistant groove having a depth exceeding 30% of the thickness of the first insulating layer or the second insulating layer. The electrostatic chuck for controlling the temperature of the loaded substrate, as described in claim 1, wherein the first insulating layer and the second insulating layer in the heat blocking region have respective heat blocking grooves (111, 121). The electrostatic chuck for controlling the temperature of the loaded substrate, as described in claim 2, wherein the two heat-resistant grooves in the heat-blocking zone are at upper and lower corresponding positions. The electrostatic chuck for controlling the temperature of the loaded substrate according to the first aspect of the invention, wherein the heat blocking zone comprises a plurality of heat blocking grooves, and each of the heat blocking grooves is distributed in an annular shape on the upper surface or the lower surface. The electrostatic chuck for controlling the temperature of the loaded substrate, as described in claim 4, wherein the plurality of heat-resistant grooves are uniformly distributed in an annular shape. The electrostatic chuck for controlling the temperature of the loaded substrate, as described in claim 1, wherein the heat-resistant groove has a depth less than 80% of a thickness of the first insulating layer or the second insulating layer. For controlling the loaded substrate as described in claim 2 The electrostatic chuck of the temperature, wherein the heat-resistant groove (111) and the heat-resistant groove (121) are substantially centered on a center point of the electrostatic chuck and have a closed circumference. The electrostatic chuck for controlling the temperature of the loaded substrate as described in claim 2, wherein the heat-resistant groove (111) or the heat-resistant groove (121) has a longitudinal section of any one of the following shapes or A variety of: - triangular; - rectangular; - trapezoidal; - inverted trapezoidal; and - fan shaped. A plasma processing apparatus for plasma-treating a substrate, the substrate being carried by an electrostatic chuck, wherein the electrostatic chuck is an electrostatic chuck according to any one of claims 1 to 8. .