JP4557814B2 - Plasma processing equipment - Google Patents

Description

  The present invention relates to a plasma processing apparatus such as a dry etching apparatus, a sputtering apparatus, and a CVD apparatus.

  In Patent Document 1, in order to improve the thermal conductivity between the substrate susceptor and the lower surface of the substrate, to make the substrate temperature uniform and to increase the accuracy of control of the substrate temperature, a supply port provided on the substrate susceptor side is disclosed. A plasma processing apparatus is disclosed in which a heat transfer gas such as helium is introduced into a gap between a substrate lower surface and a substrate susceptor.

  Patent Document 2 discloses a plasma processing apparatus in which a supply port for a heat transfer gas introduced into a gap between a substrate lower surface and a substrate susceptor is a porous insulator such as a porous ceramic. By using a porous insulator as the heat transfer gas supply port, electrical insulation between the substrate and the substrate susceptor is improved, and local abnormal discharge between the substrate and the substrate susceptor is prevented. The

  When the heat transfer gas supply port is formed of a porous material, a large number of micropores communicating with each other form a heat transfer gas flow path. However, the flow path of the heat transfer gas composed of a large number of micro holes has a non-uniform flow path diameter, and as a result, abnormal discharge is likely to occur between the wall surfaces of the flow paths (micro holes). The reason will be described in detail below.

Pashen's law is known for the discharge between two opposing electrodes. According to Paschen's law, the voltage at which discharge begins between two electrodes (discharge start voltage) is a function of the gas pressure between the electrodes and the distance between the electrodes. The graph of FIG. 12 conceptually shows Paschen's law. The horizontal axis the product of the distance d between the pressure P and the electrode, when the discharge start voltage V _s to the longitudinal axis, the relationship between the two becomes downwardly convex curve having an extreme value Pd _e. Therefore, when the product P × d of the pressure P and the distance d is smaller than the extreme value Pd _e , the discharge start voltage V _s becomes lower as the distance d is larger, and discharge is more likely to occur. Conversely, if the product P × d of the pressure P and the distance d is greater than the extreme value Pd _e, the distance d becomes larger as the discharge starting voltage V _s is increased, the discharge does not easily occur.

Passage diameter of the heat transfer gas in the porous substance is generally averages about 30～400Myuemu, when the opposing channel walls regarded as electrodes, the product Pd ₁ of the pressure P and the distance d is smaller than the extremum Pd _e . However, the flow path composed of the micropores of the porous material has a large variation in the flow path diameter between the flow paths, and there is a flow path that reaches about 400 to 1500 μm. For the flow path channel diameter is larger than the average value, the value of the product Pd ₁ of the pressure P and the inter-electrode distance d is increased (see arrow A1 in FIG. 12), the discharge starting voltage V _s decreases. Therefore, abnormal discharge is likely to occur in the flow path having a larger diameter than the average value at the heat transfer gas supply port made of a porous material.

  Abnormal discharge generated on the lower surface side of the substrate causes damage to the substrate and significantly affects the processing quality of the plasma processing apparatus. Therefore, it is necessary to prevent not only the abnormal discharge between the substrate and the substrate susceptor but also the abnormal discharge between the flow path walls of the heat transfer gas. Also, it is necessary to reliably prevent the occurrence of abnormal discharge at other locations on the lower surface side of the substrate.

  In the case of a dry etching apparatus, it is necessary to apply a high voltage to the electrode if the material to be etched is a material that is difficult to etch. Under such a high voltage, various abnormal discharges are easily generated on the lower surface side of the substrate, and the substrate is significantly damaged when the abnormal discharge occurs. Specifically, the high-frequency voltage applied between the electrodes of the reactive ion etching apparatus has a frequency of 13.5 to 6 MHz and a voltage of 300 to 900 V if the material to be etched is a general material such as silicon. . On the other hand, when the material to be etched is a material that is difficult to etch such as noble metals such as platinum, gold, indium and nickel, the frequency is about 500 kHz and the voltage reaches about 3 to 4 kV.

JP-A-11-330215 Japanese Patent Laid-Open No. 11-238596

  An object of the present invention is to prevent occurrence of abnormal discharge on the lower surface side of a substrate in a plasma processing apparatus that supplies a heat transfer gas to the lower surface side of the substrate.

  1st invention consists of an insulating material, the electrode for electrostatically adsorbing | sucking a board | substrate and hold | maintaining on an upper surface is arrange | positioned inside, and the insulation in which the 1st accommodation hole penetrated from the said upper surface to a lower surface was formed A plate member and a metal material, the insulating plate member is fixed on the upper surface, and a second receiving hole having a hole size larger than the first receiving hole penetrating from the upper surface to the lower surface is the first member of the insulating plate member. A metal plate member that is formed at a position corresponding to the one accommodation hole and to which a high-frequency voltage for plasma generation is applied, and made of an insulating material, and is accommodated in the first accommodation hole of the insulation plate member, A first gas supply in which a plurality of first gas supply holes penetrating from the upper end surface to the lower end surface are formed, and an upper end opening of the first gas supply hole is opened at the upper surface of the insulating plate member A metal plate member made of an insulating material A second gas supply hole accommodated in the second accommodation hole and having a hole size larger than the first gas supply hole is formed so as to penetrate from the upper end surface to the lower end surface, and the second gas supply hole The heat transfer gas is supplied from the lower end opening of the first gas supply port, and the heat transfer gas flows from the upper end opening of the second gas supply hole into the lower end opening of the first gas supply hole, A second gas supply member that is supplied from the upper end opening to a gap between the upper surface of the insulating plate member and the lower surface of the substrate, at least the upper end surface of the second gas supply member, and the lower surface of the insulating plate member And an insulating adhesive layer formed between the two. A plasma processing apparatus is provided.

  The present invention can be applied to various plasma processing apparatuses such as a dry etching apparatus including a reactive ion etching type and an inductively coupled plasma type, a sputtering apparatus, and a CVD apparatus. The insulating plate member, the first gas supply member, and the second gas supply member are made of ceramic, for example. The metal plate member is made of, for example, aluminum. The insulating adhesive layer is made of, for example, a silicon-based adhesive. The heat transfer gas is made of helium, for example.

  The heat transfer gas is supplied to the lower end opening of the second gas supply hole formed in the second gas supply member, the second gas supply hole, the upper end opening of the second gas supply hole, and the plurality of first gas supplies. The gas is supplied to the gap between the insulating plate member and the substrate through the lower end opening of the hole, the first gas supply hole, and the upper end opening of the first gas supply hole. Therefore, the thermal conductivity between the insulating plate member and metal plate member and the lower surface of the substrate is improved.

  Further, both the insulating plate member and the first gas supply member facing the lower surface of the substrate through the gap are made of an insulating material. Therefore, electrical insulation between the metal plate member to which the high-frequency voltage is applied and the lower surface of the substrate is high, and local abnormal discharge between the substrate, the insulating plate member, and the metal plate member can be prevented. .

  A plurality of first gas supply holes, each having a hole size smaller than the second gas supply hole of the second gas supply member, are provided in the first gas supply member made of an insulating material. Heat transfer gas is supplied from the hole to the gap between the insulating plate member and the substrate. The first gas supply hole has a minute hole size. Specifically, the hole size of the first gas supply hole is 50 μm or more and 300 μm or less, and the hole size of the second gas supply hole is 300 μm or more and 700 μm or less.

  Since the first gas supply hole is formed so as to penetrate from the upper end surface to the lower end surface of the first gas supply member made of an insulating material, the first gas supply hole has a hole size between the plurality of first gas supply holes. There is little variation. Accordingly, it is possible to prevent the occurrence of local abnormal discharge between the hole walls of the first gas supply hole due to the variation in the hole size.

In order to increase the electrostatic attraction force to the substrate and prevent the occurrence of abnormal discharge between the walls of the first gas supply hole, the area of the upper end surface of the first gas supply member is as small as possible, It is preferable that the hole size of the first gas supply hole is as small as possible, and as many first gas supply holes as possible are formed in the first gas supply member. For example, when the area of the upper end surface of the first gas supply member is 11 mm ² or more and 16 mm ² or less, it is preferable to provide 30 or more first gas supply holes having a hole size of 50 μm or more and 300 μm or less as described above. . However, if a large number of first gas supply holes are provided in the first gas supply member having a small end surface area, the first gas supply hole is formed on the outermost surface side of the first gas supply member. Therefore, the outer peripheral surface of the first gas supply member is charged during the generation of plasma in which a high frequency voltage is applied to the metal plate member. In particular, a portion of the outer peripheral surface of the first gas supply member that is adjacent to the lower end surface of the first gas supply member is strongly charged. Local abnormal discharge is likely to occur between this part and the part facing the second accommodation hole on the upper surface of the metal plate member that is a conductor.

  In the first invention, an insulating adhesive layer is provided between the upper end surface of the second gas supply member and the lower surface of the insulating plate member that constitute at least a part of the path connecting these portions. By providing this insulating adhesive layer, the potential difference between these parts is reduced. Further, the heat transfer gas does not enter between the upper end surface of the second gas supply member and the lower surface of the insulating plate member. Therefore, generation | occurrence | production of abnormal discharge between the above-mentioned parts can be prevented.

  More specifically, a metal-based adhesive layer that fixes the insulating plate member and the metal plate member to each other is provided between the lower surface of the insulating plate member and the upper surface of the metal plate member.

  The metal-based adhesive layer is made of, for example, a brazing material containing indium. In order to absorb the difference in thermal expansion between the metal plate member and the insulating plate member, it is necessary to fix the insulating plate member and the metal plate member with a metal adhesive that is more deformable than a resin adhesive. However, since the metal-based adhesive layer has high conductivity, the presence of the metal-based adhesive layer is more likely to cause abnormal discharge between the two parts. In the first invention, since the insulating adhesive layer is provided between the upper end surface of the second gas supply member and the lower surface of the insulating plate member constituting a part of the above-described path, the metal-based adhesive layer In spite of having provided, abnormal discharge between the above-mentioned parts can be prevented.

  Preferably, the first accommodation hole is disposed on an upper surface side of the insulating plate member, has a hole size corresponding to the first gas supply member, and at least the upper end surface of the first gas supply member. A hole body in which the side is accommodated, a seat which is disposed on the lower surface side of the insulating plate member, has a hole diameter corresponding to the second gas supply member, and accommodates the upper end surface side of the second gas supply member And the insulating adhesive layer includes a gap between an upper end surface of the second gas supply member and a bottom wall of the counterbore portion, and an upper end surface side of the second gas supply member. Is formed in a gap between the outer peripheral surface of the second gas supply member and the peripheral wall of the counterbore part, and a gap between the outer peripheral surface on the upper end surface side of the second gas supply member and the peripheral wall of the second accommodation hole. .

  By providing the counterbore part, the path connecting the two parts is bent and the distance is increased. As a result, abnormal discharge between these two parts can be prevented more reliably.

  Preferably, the second gas supply member has a fitting hole at an upper end surface thereof, and a lower end surface side of the first gas supply member is fitted into the fitting hole.

  Providing this fitting hole also lengthens the path connecting the two parts described above, and can more reliably prevent abnormal discharge.

  The second invention is made of an insulating material, an electrode for electrostatically adsorbing and holding the substrate on the upper surface is disposed inside, and a first accommodation hole penetrating from the upper surface to the lower surface is formed, The first accommodation hole includes a hole main body disposed on the upper surface side of the insulating plate member and a counterbore portion having a larger hole size than the main hole main body disposed on the lower surface side of the insulating plate member. The insulating plate member is fixed to the upper surface, and a second receiving hole penetrating from the upper surface to the lower surface is formed at a position corresponding to the first receiving hole of the insulating plate member. And a metal plate member to which a high-frequency voltage for generating plasma is applied, and an insulating material, and an upper end surface side is accommodated in the hole body of the first accommodation hole of the insulating plate member, and from the upper end surface A plurality of first gas supply holes penetrating to the lower end surface are formed. And an upper end opening of the first gas supply hole is opened at the upper surface of the insulating plate member, and is made of an insulating material, and is more than the first gas supply member. The outer dimension is large, and is accommodated in the second accommodation hole of the metal plate member, the upper end surface side is accommodated in the counterbore portion of the first accommodation hole of the insulating plate member, and the upper end surface is A fitting hole into which the lower end surface side of the first gas supply member is fitted is formed, and a second gas supply hole having a larger hole size than the first gas supply hole penetrates from the upper end surface to the lower end surface. The heat transfer gas is formed and supplied from the lower end opening of the second gas supply hole, and the heat transfer gas flows into the lower end opening of the first gas supply hole from the upper end opening of the second gas supply hole. The insulation from the upper end opening of the first gas supply hole A second gas supply member supplied to a gap between the upper surface of the member and the lower surface of the substrate; at least an upper end surface of the second gas supply member; and a bottom wall of a counterbore portion of the first accommodation hole Between the outer peripheral surface of the second gas supply member and the peripheral wall of the spot facing portion of the first accommodation hole, and the outer peripheral surface of the second gas supply member and the peripheral wall of the second accommodation hole And an insulating adhesive layer formed therebetween. A plasma processing apparatus is provided.

  The third invention is an insulating material made of an insulating material, in which an electrode for electrostatically adsorbing and holding the substrate on the upper surface is disposed inside, and a first accommodation hole penetrating from the upper surface to the lower surface is formed. A plate member and made of a metal material, the insulating plate member is fixed on the upper surface, and a second accommodation hole having the same hole size as the first accommodation hole corresponds to the first accommodation hole of the insulation plate member. A metal plate member formed so as to penetrate from the upper surface to the lower surface at a position and to which a high-frequency voltage for plasma generation is applied, and an insulating material, and in the first accommodation hole of the insulating plate member A plurality of first gas supply holes that are accommodated and penetrate from the upper end surface to the lower end surface are formed, and an upper end opening of the first gas supply hole opens at the upper surface of the insulating plate member. A gas supply member and an insulating material, the metal plate A second gas supply that is accommodated in the second accommodation hole of the material and whose upper end surface is accommodated in the first accommodation hole of the insulating plate member and has a hole size larger than that of the first gas supply hole. A hole is formed so as to penetrate from the upper end surface to the lower end surface, heat transfer gas is supplied from the lower end opening of the second gas supply hole, and the heat transfer gas is opened at the upper end of the second gas supply hole From the upper end opening of the first gas supply hole to the gap between the upper surface of the insulating plate member and the lower surface of the substrate. A second gas supply member having the same outer dimensions as the gas supply member, a gap between at least the outer peripheral surface of the first gas supply member and the peripheral wall of the first accommodation hole, the second gas supply member A gap between the outer peripheral surface of the first housing hole and the peripheral wall of the first receiving hole, and the second gas Characterized in that it comprises an insulating adhesive layer formed in the gap between the outer peripheral surface and the peripheral wall of the second housing hole of the supply member, to provide a plasma processing apparatus.

  According to the plasma processing apparatus of the present invention, various abnormalities that occur on the lower surface side of the substrate while ensuring good thermal conductivity by supplying heat transfer gas to the gap between the insulating plate member and the metal plate member and the lower surface of the substrate. All discharge, that is, abnormal discharge between the substrate and the insulating plate member and the metal plate member, abnormal discharge between the hole walls of the first gas supply hole, and abnormal discharge between the first gas supply member and the metal plate member Can be prevented. Therefore, it is possible to prevent damage to the substrate due to abnormal discharge occurring on the lower surface side of the substrate and improve the stability of the plasma processing.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

(First embodiment)
FIG. 1 shows a reactive ion etching type dry etching apparatus 1 which is a plasma processing apparatus according to a first embodiment of the present invention. The dry etching apparatus 1 is suitable for etching a layer made of a material that is difficult to etch, such as a noble metal such as platinum, gold, indium, or nickel, formed on the substrate 2.

  The dry etching apparatus 1 includes a vacuum container or a chamber 3 in which a substrate 2 is disposed. An upper electrode 4 is disposed in the upper part of the chamber 3. A substrate susceptor 6 that functions as a lower electrode to which a high-frequency voltage is applied and a holder for the substrate 2 is disposed in the lower portion of the chamber 3. The upper electrode 4 and the chamber 3 are grounded. On the other hand, a later-described electrode plate 24 included in the substrate susceptor 6 is electrically connected to a high-frequency power source 7 for generating plasma. The high frequency power supply 7 applies a high voltage to the substrate susceptor 6 in order to etch a material that is difficult to etch. Specifically, the frequency of power applied from the high frequency power supply 7 to the substrate susceptor 6 is about 500 kHz, and the applied voltage reaches about 3 to 4 kV. Electrostatic chucking electrodes 8A and 8B described later included in the substrate susceptor 6 are electrically connected to DC power supplies 9A and 9B.

  An etching gas supply device 11 for supplying an etching gas is connected to an etching gas flow path inlet 3 a provided in the chamber 3. The etching gas supply device 11 includes an MFC (mass flow controller) or the like, and can supply an etching gas at a desired flow rate into the chamber 3 from the etching gas inlet 3a. The chamber is provided with an exhaust port 3b. A vacuum exhaust device 12 having a vacuum pump or the like is connected to the exhaust port 3b. Further, the chamber 3 is provided with a gate 3c for loading and unloading the substrate 2.

  The dry etching apparatus 1 includes a refrigerant supply apparatus 13 that supplies and circulates a refrigerant into the substrate susceptor 6. Further, the dry etching apparatus 1 supplies a heat transfer gas such as helium to the gap 14 (see FIG. 4) between the upper surface of the substrate susceptor 6 and the lower surface 2a of the substrate 2 during dry etching, and transmits from the gap 14 after the dry etching is completed. A heat transfer gas supply / discharge device 16 for exhausting the hot gas is provided. The configuration and function of the heat transfer gas supply / discharge device 16 will be described later.

  Further, the dry etching apparatus 1 includes a push-up device 17 for pushing up the substrate 2 from the upper surface of the substrate susceptor 6 when the substrate 2 is transported. The push-up device 17 includes four push-up pins 18 extending in the vertical direction and a base 19 to which the base end side of the push-up pins 18 is fixed. The base 19 is fixed to the tip of the rod 21 a of the cylinder 21 disposed outside the bottom of the chamber 3. The rod 21a of the cylinder 21 communicates with the inside of the chamber 3, but is accommodated in a housing 22 that is blocked from the outside (atmosphere). When the rod 21 a is in the protruding position, the tip of the push-up pin 18 protrudes from the upper surface of the substrate susceptor 6 and pushes up the substrate 2. On the other hand, if the rod 21 a is in the retracted position, the tip of the push-up pin 18 is stored in the substrate susceptor 6.

  Next, the substrate susceptor 6 will be described with reference to FIGS. As shown in detail in FIG. 3, the substrate susceptor 6 includes a holding plate (insulating plate member) 23 that holds the substrate 2 on the upper surface 23a by electrostatic adsorption, and an electrode plate (metal) on which the holding plate 23 is fixed on the upper surface 24a. Plate member) 24. The substrate susceptor 6 is disposed at the bottom of the chamber 3, and a pedestal member 26 on which the holding plate 23 and the electrode plate 24 are placed, and the holding plate 23 and the electrode plate 24 are fixed to the pedestal member 26. Frame bodies 27 and 28 for carrying out. Further, the substrate susceptor 6 includes an annular plate 29 that covers the electrode plate 24 and the upper portions of the frame bodies 27 and 28 so that only the holding plate 23 is exposed in plan view.

  The holding plate 23 is made of ceramic which is an insulating material. As schematically shown in FIGS. 3 and 4, electrostatic adsorption electrodes 8 </ b> A and 8 </ b> B are built in the vicinity of the upper surface 23 a inside the holding plate 23. As schematically shown in FIG. 1, the electrostatic chucking electrodes 8A and 8B are electrically connected to DC power supplies 9A and 9B.

  Referring to FIGS. 2 to 5, the holding plate 23 has a center position in plan view, and upper receiving holes (first first holes) penetrating from the upper surface 23a to the lower surface 23b at four positions that are point-symmetric with respect to the center. (Accommodating hole) 31 is formed. Accordingly, in the present embodiment, a total of five upper accommodation holes 31 are formed in the holding plate 23. As clearly shown in FIG. 5, the upper accommodation hole 31 includes a hole body 32 positioned on the upper surface 23 a side of the holding plate 23 and a counterbore portion 33 positioned on the lower surface 23 b side. The hole body 32 and the counterbore part 33 are all circular in plan view. The diameter D2 of the spot facing portion 33 is larger than the diameter D1 of the hole body 32. Specifically, the diameter D1 of the hole body 32 is about 4 mm to 6 mm, whereas the diameter D2 of the counterbore 33 is about 8 mm to 10 mm. The diameter D1 of the hole body 32 corresponds to a diameter D3 (see FIG. 6B) of a nozzle member 43 described later. The diameter D2 of the spot facing 33 corresponds to the diameter D4 (see FIG. 7B) of the inlet member 47 described later.

  Referring to FIGS. 2, 4, and 5, the upper surface 23 a of the holding plate 23 is provided with a columnar fine protrusion 34 that protrudes upward except for the vicinity of the outer peripheral edge. The protrusions 34 are disposed substantially uniformly on the upper surface 23a. Further, a surrounding portion 36 (shown only in FIG. 2) having the same height as the protrusion 34 is provided in the vicinity of the outer peripheral edge of the upper surface 23a. Therefore, as shown in FIG. 4, a very fine closed gap 14 exists between the substrate 2 held on the holding plate 23 by electrostatic adsorption and the upper surface 23 a of the holding plate 23.

  The electrode plate 24 is made of aluminum, which is a conductive metal material. As schematically shown in FIG. 1, the electrode plate 24 is electrically connected to a high-frequency power source 7 for generating plasma. Further, as schematically shown in FIG. 1, a refrigerant circulation channel 37 is formed inside the electrode plate 24. The refrigerant circulation channel 37 is connected to the refrigerant supply device 13 via the refrigerant channel 38. The refrigerant supplied from the refrigerant supply device 13 through the refrigerant flow path 38 circulates in the refrigerant circulation flow path 37, whereby the electrode plate 24 is cooled. By cooling the electrode plate 24, the substrate 2 held by the holding plate 23 is cooled.

  The electrode plate 24 is formed with a lower accommodation hole (second accommodation hole) 39 penetrating from the upper surface 24 a to the lower surface 24 b at a position corresponding to the upper accommodation hole 31 of the holding plate 23. In the present embodiment, the lower accommodation hole 39 is circular in plan view, and the diameter D5 is the same as the diameter D2 of the spot facing portion 33 of the upper accommodation hole 31 formed in the holding plate 23. Similar to the counterbore part 33, the diameter D5 of the lower receiving hole 39 corresponds to a diameter D4 (see FIG. 7B) of the inlet member 47 described later.

  The electrode plate 24 is anodized on the surface in order to provide insulation. However, the upper surface 24a is not anodized. As shown in FIG. 4, a metal adhesive layer 41 having conductivity is formed between the lower surface 23 b of the holding plate 23 and the upper surface 24 a of the electrode plate 24, and the metal adhesive layer 41 holds the metal adhesive layer 41. The plate 23 and the electrode plate 24 are fixed to each other. The thermal expansion coefficient of the aluminum electrode plate 24 is larger than the thermal expansion coefficient of the ceramic holding plate 23, and the thermal expansion or extension of the electrode plate 24 due to the temperature rise during the plasma processing is larger than that of the holding plate 23. In order to absorb this difference in thermal expansion, it is necessary to fix the holding plate 23 and the electrode plate 24 with a metal adhesive that is more deformable than a resin adhesive. In the present embodiment, the metal adhesive constituting the metal adhesive layer 41 is made of a brazing material containing indium.

  Referring to FIG. 3, the pedestal member 26 is formed with an accommodation hole 42 at a position corresponding to the upper accommodation hole 31 of the holding plate 23 and the lower accommodation hole 39 of the electrode plate 24. The accommodation hole 42 penetrates the base member 26 from the upper surface to the lower surface.

  The substrate susceptor 6 includes nozzle members (first gas supply members) 43 respectively accommodated in the five upper accommodation holes 31 of the holding plate 23. The nozzle member 43 functions as a supply port to the gap 14 (see FIG. 4) of the heat transfer gas supplied from the heat transfer gas supply / discharge device 16.

  The nozzle member 43 is made of ceramic which is an insulating material. 6A and 6B, the nozzle member 43 has a short cylindrical shape as a whole. As described above, the nozzle member 43 has a diameter D3 corresponding to the diameter D1 of the hole body 32 of the counterbore portion 33 of the upper receiving hole 31. The diameter D3 of the nozzle member 43 is constant in the height direction.

  In the nozzle member 43, a plurality of upper gas supply holes (first gas supply holes) 44 penetrating from the upper end surface 43a to the lower end surface 43b are formed. In the present embodiment, the upper gas supply hole 44 is circular in plan view, and the diameter d1 is constant in the longitudinal direction. For example, the upper gas supply hole 44 is formed in the nozzle member 43 by laser irradiation. An upper end opening 44 a of the upper gas supply hole 44 opens at the upper surface 23 a of the holding plate 23. The lower end surface 43b of the nozzle member 43 is formed with a circular lower end recess 46 in plan view. The lower end opening 44 b of the upper gas supply hole 44 is opened by the lower end recess 46.

The electrostatic chucking electrodes 8A and 8B cannot be disposed on the portion of the holding plate 23 where the nozzle member 43 is disposed. Therefore, in order to increase the electrostatic attraction force acting on the substrate 2, the area of the upper end surface 43 a of the nozzle member 43 is preferably smaller than the area of the upper surface 23 a of the holding plate 23. Referring also to FIG. 12, the product of the pressure P of the heat transfer gas and the inter-electrode distance d (diameter d1) in each upper gas supply hole 44 is smaller than the extreme value Pd _e (reference symbol Pd in FIG. 12). ₁ ). Therefore, in consideration of Paschen's law, from the viewpoint of preventing the occurrence of abnormal discharge, the diameter d1 of the upper gas supply hole 44 is set small to reduce the distance between the hole walls, and the nozzle member 43 has a large number of upper gas supply holes. 44 must be formed to reduce the pressure of the heat transfer gas in each upper gas supply hole 44. Further, the larger the number of the upper gas supply holes 44, the faster the heat transfer gas can be supplied to the gap 14 between the holding plate 23 and the substrate 2. Conversely, when the number of minute upper gas supply holes 44 is reduced, the pressure of the heat transfer gas in the upper gas supply holes 44 tends to increase, and the heat transfer gas to the gap 14 between the holding plate 23 and the substrate 2 is increased. Rapid supply tends to be hindered. For these reasons, the area of the upper end surface 43a of the nozzle member 43 is as small as possible, the diameter d1 of the upper gas supply hole 44 is as small as possible, and the nozzle member 43 has as many upper gas supply holes 44 as possible. Preferably it is formed. In the present embodiment, the diameter D3 of the nozzle member 43 is 4 mm, the area is 12.56Mm ² of the upper end surface 43a, the diameter d1 the upper gas supply hole 44 of 200μm is provided 37. In the case of the nozzle member 43 having an area of the upper end surface 43a of about 11 mm ^{2 to} 16 mm ^2, it is preferable to provide about 30 to 45 upper gas supply holes 44 having a diameter d1 of about 50 μm to 300 μm.

  The substrate susceptor (lower electrode) 6 includes inlet members (second gas supply members) 47 respectively accommodated in the five lower accommodation holes 39 of the electrode plate 24. The inlet member 47 functions as a flow path for the heat transfer gas from the heat transfer gas supply / exhaust device 16 toward the nozzle member 43.

  The inlet member 47 is made of ceramic which is an insulating material. Referring to FIGS. 7A and 7B together, the inlet member 47 has a generally elongated cylindrical shape. The inlet member 47 has a diameter D4 corresponding to the diameters D2 and D5 of the spot facing portion 33 and the lower receiving hole 39. A diameter-expanded portion 47c having a slightly larger diameter D4 is provided below the center of the inlet member 47 in the height direction.

  The inlet member 47 is formed with one lower gas supply hole (second gas supply hole) 48 penetrating from the upper end surface 47a to the lower end surface 47b. In the present embodiment, the lower gas supply hole 48 is circular in plan view, and the diameter d2 is constant in the longitudinal direction and is 500 μm. In order to enable rapid supply of heat transfer gas to the upper gas supply hole 44, The diameter d2 is preferably about 300 μm to 700 μm. For example, the lower gas supply hole 48 is formed in the inlet member 47 by drilling. A circular fitting hole 49 is formed in the upper end surface 47a of the inlet member 47 in a plan view. An upper end opening 48 a of the lower gas supply hole 48 is opened by the fitting hole 49. On the other hand, the lower end opening 48 b of the lower gas supply hole 48 opens at the lower end surface 47 b of the inlet member 47.

  As shown in FIG. 3, the substrate susceptor (lower electrode) 6 includes a flow path member 51 that is a cylindrical body that is open at both ends and is accommodated in the five accommodation holes 42 of the base member 26. The heat transfer gas flow path 51a (illustrated in FIG. 4) formed inside the flow path member 51 has an upper end opened at the upper end surface of the flow path member 51 and a lower end side transferred by the heat transfer gas supply / discharge device 16. It is connected to a hot gas supply line 56 (shown in FIG. 1).

  Referring to FIG. 4, most of the nozzle member 43 including the upper end surface 43 a and the central portion in the height direction is accommodated in the hole body 32 of the upper accommodation hole 31 formed in the holding plate 23. However, the vicinity of the lower end surface 43 b of the nozzle member 43 protrudes into the spot facing portion 33. Most of the inlet member 47 is accommodated in a lower accommodation hole 39 formed in the electrode plate 24, including a lower end surface 47 b and a central portion in the height direction. However, the vicinity of the upper end surface 47 a of the inlet member 47 is accommodated in the spot facing portion 33. The vicinity of the lower end surface 43 b of the nozzle member 43 is fitted into a fitting hole 49 formed in the upper end surface 47 a of the inlet member 47.

  An insulating adhesive layer 52 that fixes the nozzle member 43 and the inlet member 47 to the holding plate 23 and the electrode plate 24 is formed. Specifically, the gap between the outer peripheral surface 43 c of the nozzle member 43 and the peripheral wall 32 a of the hole body 32 of the upper receiving hole 31, the upper end surface 47 a of the inlet member 47 and the bottom wall 33 a of the counterbore portion 33 of the upper receiving hole 31. The gap, the gap between the outer peripheral surface 47d on the upper end surface 47a side of the inlet member 47 and the peripheral wall 33b of the spot facing portion 33, and the gap between the outer peripheral surface 47d of the inlet member 47 and the peripheral wall 39a of the lower receiving hole 39 are insulated. An adhesive layer 52 is provided. In the present embodiment, the insulating adhesive layer 52 is made of a silicon-based adhesive. The insulating adhesive layer 52 functions as an insulating material for preventing the occurrence of abnormal discharge, as will be described in detail later, in addition to fixing the nozzle member 43 and the inlet member 47.

  The upper gas supply hole 44 of the nozzle member 43 has an upper end opening 44 a that opens at the upper surface 23 a of the holding plate 23, and communicates with the gap 14 between the holding plate 23 and the substrate 2. On the other hand, the lower end opening 44 b of the upper gas supply hole 44 opens into the lower end recess 46 of the lower end surface 43 b of the nozzle member 43, and communicates with the upper end opening 48 a of the lower gas supply hole 48 of the inlet member 47 via the lower end recess 46. is doing. The lower end opening 48 b of the lower gas supply hole 48 is connected to the heat transfer gas supply / discharge device 16 via the heat transfer gas channel 51 a of the channel member 51. Therefore, the heat transfer gas from the heat transfer gas supply / discharge device 16 is supplied to the lower end opening 48b of the lower gas supply hole 48, and the lower gas supply hole 48, the upper end opening 48a of the lower gas supply hole 48, and the lower end recess. 46, the gas is supplied to the gap 14 between the holding plate 23 and the substrate 2 through the lower end opening 44 b of the plurality of upper gas supply holes 44, the upper gas supply hole 44, and the upper end opening 44 a of the upper gas supply hole 44.

  2 and 3, the holding plate 23 is provided with four receiving holes 81 penetrating from the upper surface 23a to the lower surface 23b at a point-symmetrical position with respect to the center in plan view. The accommodation hole 81 accommodates the upper end side of a cylindrical guide cylinder member 82 as a whole. Further, the electrode plate 24 is provided with a receiving hole 83 penetrating from the upper surface 24 a to the lower surface 24 b at a position corresponding to the receiving hole 81. The accommodation hole 83 accommodates the lower end side and the center portion of the guide cylinder member 82. Further, the pedestal member 26 is provided with a through hole 84 penetrating from the upper surface to the lower surface at a position corresponding to the accommodation hole 83. The guide tube member 82 is formed with a guide hole 82a penetrating from the upper end to the lower end. The tip end side of the push-up pin 18 of the push-up device 17 is accommodated in the through hole 84 and the guide hole 82a so as to be movable in the vertical direction.

  The heat transfer gas supply / exhaust device 16 will be described with reference to FIG. The heat transfer gas supply / discharge device 16 includes a heat transfer gas supply line 56 that communicates with the gap 14 via the flow path member 51, the inlet member 47, and the nozzle member 43, and a heat transfer gas exhaust line that similarly communicates with the gap 14. 57. The heat transfer gas supply line 56 has one end connected to the heat transfer gas source 58 and the other end connected to the substrate susceptor 6 (lower electrode) side. The heat transfer gas supply line 56 is provided with an MFC 59 and a cut-off valve 61A. On the other hand, one end of the heat transfer gas exhaust line 57 is connected to the vacuum pump 62 for suction, and the other end is connected to the substrate susceptor 6 (lower electrode) side. In the heat transfer gas exhaust line 57, a cutoff valve 61B, an automatic pressure control valve 63, and a vacuum gauge 64 are provided. Furthermore, the heat transfer gas supply / discharge device 16 has a heat transfer gas supply line 56 closer to the substrate susceptor 6 (lower electrode) than the cut-off valve 61A, and a heat transfer gas supply closer to the substrate susceptor 6 (lower electrode) than the cut-off valve 61B. A bypass line 66 connecting the hot gas exhaust line 57 is provided. The bypass line 66 is provided with a cutoff valve 61C. Furthermore, the heat transfer gas supply / discharge device 16 includes a heat transfer gas supply line 56 closer to the substrate susceptor 6 (lower electrode) than the cut-off valve 61A, and a heat transfer gas closer to the vacuum pump 62 than the automatic pressure control valve 63. A bypass line 67 that connects the exhaust line 57 is provided. The bypass line 67 is provided with a cutoff valve 61D.

  When supply of the heat transfer gas to the gap 14 is started, the cutoff valves 61A, 61B, 61C are first opened, and the cutoff valve 61D is closed. Accordingly, the heat transfer gas is supplied from the heat transfer gas source 58 to the gap 14 through the bypass line 66 and the heat transfer gas exhaust line 57 as well as the heat transfer gas supply line 56. After the heat transfer gas in the gap 14 is increased to a predetermined pressure, the cutoff valve 61C is closed, and the automatic pressure control valve 63 maintains the gap 14 at the predetermined pressure according to the detected pressure of the vacuum gauge 64. After the dry etching process is completed, the cut-off valve 61A is closed, while the cut-off valves 61B to 61D are opened. Thus, the heat transfer gas in the gap 14 is quickly exhausted not only through the heat transfer gas exhaust line 57 but also through the bypass lines 66 and 67 and the heat transfer gas supply line 56.

  A controller 68 schematically shown only in FIG. 1 includes an etching gas supply device 11, an evacuation device 12, a refrigerant supply device 13, a heat transfer gas supply / discharge device 16, a high frequency power supply 7, DC power supplies 9 </ b> A and 9 </ b> B, and a cylinder 21. The operation of the entire dry etching apparatus 1 is controlled.

  The operation of the dry etching apparatus 1 of this embodiment will be described. First, the inside of the chamber 3 is evacuated by the evacuation device 12, and the substrate 2 carried into the chamber 3 from the gate 3 c is placed on the holding plate 23 of the substrate susceptor (lower electrode) 6. Further, a DC voltage is applied from the DC power supplies 9A and 9B to the electrostatic chucking electrodes 8A and 8B, and the substrate 2 is held on the holding plate 23 by electrostatic chucking.

  Next, the heat transfer gas supply / discharge device 16 supplies the heat transfer gas to the gap 14 between the upper surface 23 a of the holding plate 23 and the lower surface 2 a of the substrate 2. The heat transfer gas that has flowed from the heat transfer gas supply line 56 of the heat transfer gas supply / discharge device 16 into the heat transfer gas flow path 51a of the flow path member 51 flows into the lower gas supply hole 48 of the inlet member 47 from the lower end opening 48b. Then, the gas flows from the upper end opening 48 a of the lower gas supply hole 48 into the lower end openings 44 b of the individual upper gas supply holes 44 of the nozzle member 43 through the lower end recess 46. The heat transfer gas flowing into each upper gas supply hole 44 flows into the gap 14 from the upper end opening 44a. As described above, the gap 14 is maintained at a predetermined pressure by the heat transfer gas supply / discharge device 16.

  Next, an etching gas is supplied into the chamber 3 by the etching gas supply device 11, and the inside of the chamber 3 is maintained at a predetermined pressure by the vacuum exhaust device 12. Subsequently, a high frequency voltage is applied from the high frequency power source 7 to the electrode plate 24 of the substrate susceptor 6 (lower electrode), thereby generating plasma in the chamber 3. The substrate 2 is etched by this plasma.

  During the etching, the refrigerant from the refrigerant supply device 13 is circulated through the refrigerant circulation passage 37 in the electrode plate 24, thereby cooling the substrate 2 held on the holding plate 23 by electrostatic adsorption. Since the gap 14 between the upper surface 23a of the holding plate 23 and the lower surface 2a of the substrate 2 is filled with heat transfer gas, the thermal conductivity between the holding plate 23 and the substrate 2 is good. Therefore, the temperature of the substrate 2 can be made uniform and the substrate temperature can be controlled with high accuracy.

  As described above, a high voltage (about 3 to 4 kV) is applied from the high frequency power source 7 to the electrode plate 24 in order to etch the material that is difficult to etch. However, as described in detail below, in the dry etching apparatus 1 of the present embodiment, any of various abnormal discharges on the lower surface 2a side of the substrate 2 can be prevented.

  First, both the holding plate 23 and the nozzle member 43 facing the lower surface 2a of the substrate 2 through the gap 14 are made of an insulating material. Therefore, the electrical insulation between the electrode plate 24 to which a high-frequency voltage is applied from the high-frequency power source 7 and the lower surface 2a of the substrate 2 is high, and abnormal discharge between the substrate 2 and the holding plate 23 and the electrode plate 24 occurs. Occurrence can be prevented.

  Next, the upper gas supply hole 44 of the nozzle member 43 that supplies heat transfer gas to the gap 14 between the holding plate 23 and the substrate 2 is a minute hole having a diameter d1 of about 50 μm to 300 μm (200 μm in this embodiment). is there. Further, the upper gas supply hole 44 is not a small hole provided in the porous material communicating with each other, but is a nozzle member 43 made of an insulating material subjected to a hole process penetrating from the upper end surface 43a to the lower end surface 43b. Therefore, there is little variation in the diameter d1 between the upper gas supply holes 44. Accordingly, it is possible to prevent the occurrence of local abnormal discharge between the hole walls of the upper gas supply hole 44 due to the variation in the diameter d1.

  As described above, a nozzle having a small area of the upper end surface 43a and the lower end surface 43b in consideration of increasing the electrostatic attraction force to the substrate 2 and preventing abnormal discharge between the hole walls of the first gas supply hole. The member 43 is provided with as many upper gas supply holes 44 with a minute diameter d1 as possible. For this reason, among the plurality of upper gas supply holes 44, the one formed closest to the outer peripheral surface 43 c of the nozzle member 43 and the outer peripheral surface 43 c of the nozzle member 43 are close to each other. Referring to FIG. 6B, in this embodiment, the distance α between the upper gas supply hole 44 closest to the outer peripheral surface 43c and the outer peripheral surface 43c is about 0.6 mm. Therefore, the outer peripheral surface 43c of the nozzle member 43 is charged during the plasma processing in which the high frequency voltage is applied to the electrode plate 24. Referring to FIG. 4, a portion 71 adjacent to the lower end surface 43b in the outer peripheral surface 43c of the nozzle member 43 is strongly charged. Abnormal discharge is likely to occur between this portion 71 and the portion 72 where the metal-based adhesive layer 41 formed on the upper surface 24a of the electrode plate 24, which is a conductor, faces the lower accommodation hole 39. In particular, in the present embodiment, since a high voltage is applied to the electrode plate 24 in order to etch a difficult-to-etch material, the portion 71 is more strongly charged and abnormal discharge between the portions 71 and 72 is likely to occur. As shown in FIG. 4, the path 73 connecting the portions 71 and 72 is between the outer peripheral surface 43 c of the nozzle member 43 and the peripheral wall 49 a of the fitting hole 49 and between the upper end surface 47 a of the inlet member 47 and the upper accommodation hole 31. A gap between the bottom wall 33 a of the portion 33, a gap between the outer peripheral surface 47 d of the inlet member 47 and the peripheral wall 33 b of the spot facing portion 33, and a gap between the outer peripheral surface 47 d of the inlet member 47 and the peripheral wall 39 a of the lower housing hole 39. Including.

  In the present embodiment, the gap between the upper end surface 47a of the inlet member 47 and the bottom wall 33a of the spot facing portion 33 of the upper accommodation hole 31 included in the path 73 connecting the portions 71 and 72, the outer peripheral surface 47d of the inlet member 47 and the seat. An insulating adhesive layer 52 is provided in the space between the peripheral wall 33 b of the bore 33 and the space between the outer peripheral surface 47 d of the inlet member 47 and the peripheral wall 39 a of the lower housing hole 39. By providing the insulating adhesive layer 52, the potential difference between the portions 71 and 72 is reduced. In addition, since the insulating adhesive layer 52 is filled, the heat transfer gas does not enter the voids included in the path 73 connecting these portions 71 and 72. Therefore, the occurrence of local abnormal discharge between the portions 71 and 72 can be prevented.

  In order to absorb the difference in thermal expansion between the holding plate 23 and the electrode plate 24, it is necessary to provide a metal adhesive layer 41 that is highly deformable but highly conductive. Due to the presence of the metal-based adhesive layer 41, abnormal discharge between the portions 71 and 72 is more likely to occur. However, in this embodiment, since the insulating adhesive layer 52 is provided in the gap that constitutes a part of the path 73, the abnormality between the portions 71 and 72 despite the presence of the metal-based adhesive layer 41. The occurrence of discharge can be reliably prevented.

By arranging the upper end face 47a side of the inlet member 47 in the spot facing portion 33 provided in the upper accommodation hole 31 of the holding plate 23, the path 73 is bent. The distance of the path 73 is increased due to the presence of the bent portion. Specifically, as shown in FIG. 4, the outer peripheral surface 47 d of the inlet member 47 and the peripheral wall of the counterbore portion 33 with respect to the gap between the upper end surface 47 a of the inlet member 47 and the bottom wall 33 a of the counterbore portion 33. The gap between 33b is a right angle. Also, the path 73 is bent and the distance is increased by fitting the lower end surface 43 b side of the nozzle member 43 into the fitting hole 49 provided in the upper end surface 47 a of the inlet member 47. Specifically, as shown in FIG. 4, with respect to the gap between the outer peripheral surface 43 c of the nozzle member 43 and the peripheral wall 49 a of the fitting hole 49, the inlet member 47 has an upper end surface 47 a and a peripheral wall 33 b of the spot facing portion 33. The gap between them is a right angle. Even when the path 73 is bent and lengthened, the occurrence of local abnormal discharge between the portions 71 and 72 is prevented. Referring to FIG. 12, when the parts 71 and 72 are regarded as electrodes facing each other through the path 73, the product Pd ₂ of the pressure P and the distance d is larger than the extreme value Pde, and discharge is generated as the value of the distance d is larger. The voltage V _S increases (see arrow A2). Therefore, as the length of the path 73 is longer, local abnormal discharge between the portions 71 and 72 is less likely to occur.

  As described above, in the dry etching apparatus of this embodiment, abnormal discharge between the substrate 2, the holding plate 23 and the electrode plate 24, abnormal discharge between the hole walls of the upper gas supply hole 44, and the outer peripheral surface 43 c of the nozzle member 43. The abnormal discharge between the part 71 and the part 72 facing the lower receiving hole 39 of the electrode plate 24 and the metal adhesive layer 41 can be prevented. Accordingly, it is possible to prevent the substrate 2 from being damaged due to abnormal discharge occurring on the lower surface 2a side of the substrate 2 and improve the stability of the dry etching process.

  At the end of etching, the application of the high frequency voltage from the high frequency power source 7 to the electrode plate 24 is stopped. Subsequently, after the heat transfer gas is exhausted by the heat transfer gas supply / discharge device 16 and the gap 14 is decompressed, the application of the DC voltage from the DC power supplies 9A and 9B to the electrostatic adsorption electrodes 8A and 8B is stopped and held. The holding of the substrate 2 on the plate 23 is released. Thereafter, the substrate 2 is pulled away from the holding plate 23 by the push-up device 17 and carried out of the chamber 3 from the gate 3c.

(Second Embodiment)
In the second embodiment of the present invention shown in FIG. 8, the fitting hole 49 (see FIG. 4) is not formed in the inlet member 47, and the lower end surface 43 b of the nozzle member 43 is in contact with the upper end surface 47 a of the inlet member 47. It touches. A path 73 connecting the portion 71 of the outer peripheral surface 43 c of the nozzle member 43 and the portion 72 of the electrode plate 24 and the metal-based adhesive layer 41 is between the upper end surface 47 a of the inlet member 47 and the bottom wall 33 a of the spot facing portion 33. A gap, a gap between the outer peripheral surface 47 d of the inlet member 47 and the peripheral wall 33 b of the spot facing portion 33, and a gap between the outer peripheral surface 47 d of the inlet member 47 and the peripheral wall 39 a of the lower receiving hole 39 are configured. An insulating adhesive layer 52 is formed in each of these voids, and local abnormal discharge between the portion 71 and the portion 72 is prevented.

  In the present embodiment, the diameter D4 of the inlet member 47 is set larger than that in the first embodiment, and the diameter D2 of the counterbore portion 33 and the diameter D5 of the lower receiving hole 39 are correspondingly larger than those in the first embodiment. It is set. By setting these dimensions, the length of the gap between the upper end surface 47a of the inlet member 47 and the bottom wall 33a of the spot facing portion 33 in the path 73 connecting the portions 71 and 72 is set longer. As a result, a sufficient length of the path 73 is secured, and abnormal discharge between the portions 71 and 72 can be prevented more reliably.

  Since the other configurations and operations of the second embodiment are the same as those of the first embodiment, the same elements are denoted by the same reference numerals and description thereof is omitted.

(Third embodiment)
In the third embodiment of the present invention shown in FIG. 9, no counterbore portion 33 (see FIG. 4) is formed in the upper accommodation hole 31 of the holding plate 23, and the upper end surface 47 a of the inlet member 47 is formed on the holding plate 23. Is located on the lower surface 23b. A path 73 connecting the portions 71 and 72 is a gap between the outer peripheral surface 43 c of the nozzle member 43 and the peripheral wall 49 a of the fitting hole 49, and a gap between the upper end surface 43 a of the nozzle member 43 and the lower surface 23 b of the holding plate 23. And an air gap between the outer peripheral surface 47 d of the inlet member 47 and the peripheral wall 39 a of the lower accommodation hole 39. An insulating adhesive layer 52 is formed in each of these gaps, and local abnormal discharge between the portions 71 and 72 is prevented.

  Further, the diameter D4 of the inlet member 47 and the diameter D5 of the lower receiving hole 39 are set to be larger than those in the first embodiment, and the path 73 is formed between the upper end surface 47a of the inlet member 47 and the lower surface 23b of the holding plate 23. The length of the gap is set longer. As a result, a sufficient length of the path 73 is ensured, and abnormal discharge between the portions 71 and 72 can be prevented more reliably.

  Since other configurations and operations of the third embodiment are the same as those of the first embodiment, the same elements are denoted by the same reference numerals, and description thereof is omitted.

(Fourth embodiment)
In the fourth embodiment of the present invention shown in FIG. 10, the counterbore portion 33 (see FIG. 4) is not formed in the upper accommodation hole 31 of the holding plate 23. Moreover, the fitting hole 49 (refer FIG. 4) is not formed in the upper end surface 43a of the nozzle member 43. FIG. Both the lower end surface 43 b of the nozzle member 43 and the upper end surface 47 a of the inlet member 47 are located on the lower surface 23 b of the holding plate 23. A path 73 connecting the portions 71 and 72 is formed by a gap between the upper end surface 47 a of the inlet member 47 and the lower surface 23 b of the holding plate 23. An insulating adhesive layer 52 is formed in the gap, and local abnormal discharge between the portions 71 and 72 is prevented.

  Similarly to the third embodiment, the diameter D4 of the inlet member 47 and the diameter D5 of the lower receiving hole 39 are set larger than those of the first embodiment, and the upper end surface 47a of the inlet member 47 constituting the path 73 is held. The length of the gap between the lower surface 23b of the plate 23 is set long. As a result, a sufficient length of the path 73 is secured, and abnormal discharge between the portions 71 and 72 can be prevented more reliably.

  Since the other configurations and operations of the fourth embodiment are the same as those of the first embodiment, the same elements are denoted by the same reference numerals and description thereof is omitted.

(Fifth embodiment)
In the fifth embodiment of the present invention shown in FIG. 11, the counterbore 33 (see FIG. 4) is not formed in the upper accommodation hole 31 formed in the holding plate 23. Further, the diameter D 4 of the inlet member 47 is set to be the same as the diameter D 3 of the nozzle member 43, and the upper end surface 47 a side of the inlet member 47 is accommodated in the upper accommodation hole 31. A path 73 connecting the portions 71 and 72 is formed by a gap between the outer peripheral surface 43 c of the nozzle member 43 and the peripheral wall of the upper accommodation hole 31. An insulating adhesive layer 52 is formed in the gap, and local abnormal discharge between the portions 71 and 72 is prevented. Moreover, the length L of the part accommodated in the upper side accommodation hole 31 of the nozzle member 43 is set long. As a result, a sufficient length of the path 73 is ensured, and abnormal discharge between the portions 71 and 72 can be prevented more reliably.

  Since other configurations and operations of the fifth embodiment are the same as those of the first embodiment, the same elements are denoted by the same reference numerals and description thereof is omitted.

  The present invention is not limited to the embodiments and can be variously modified. For example, the shape of the upper accommodation hole 31, the lower accommodation hole 39, the upper gas supply hole 44, the lower gas supply hole 48, etc. in plan view is not limited to a circle, but may be other shapes such as an ellipse or a rectangle. May be. Further, the upper accommodation hole 31, the lower accommodation hole 39, the upper gas supply hole 44, and the lower gas supply hole 48 are not necessarily provided in the vertical direction, and are not provided in the holding plate 23, the electrode plate 24, and the base member 26. You may form diagonally. Furthermore, the outer shape of the nozzle member 43 and the inlet member 47 is not limited to a cylindrical shape, and may be other shapes such as a prismatic shape. Although the present invention has been described by taking a reactive ion etching type dry etching apparatus as an example, the present invention can also be applied to other dry etching apparatuses including an inductively coupled plasma type. Furthermore, the present invention can be applied to other plasma processing apparatuses such as a sputtering apparatus and a CVD apparatus other than the dry etching apparatus.

The schematic diagram which shows the dry etching apparatus which concerns on 1st Embodiment of this invention. The top view of a board | substrate susceptor (lower electrode). Sectional drawing in the III-III line of FIG. The elements on larger scale of FIG. The exploded sectional view of a substrate susceptor (lower electrode). The top view of an upper side gas supply member. Sectional drawing in the VI-VI line of FIG. 6A. The top view of a lower side gas supply member. Sectional drawing in the VII-VII line of FIG. 7A. Sectional drawing of the substrate susceptor (lower electrode) of the dry etching apparatus which concerns on 2nd Embodiment of this invention. Sectional drawing of the substrate susceptor (lower electrode) of the dry etching apparatus which concerns on 3rd Embodiment of this invention. Sectional drawing of the board | substrate susceptor (lower electrode) of the dry etching apparatus which concerns on 4th Embodiment of this invention. Sectional drawing of the substrate susceptor (lower electrode) of the dry etching apparatus which concerns on 5th Embodiment of this invention. The graph which shows the relationship between the discharge start voltage, a pressure, and the distance of distance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Dry etching apparatus 2 Substrate 2a Lower surface 3 Chamber 3a Etching gas inflow port 3b Exhaust port 3c Gate 4 Upper electrode 6 Substrate susceptor (lower electrode)
7 High-frequency power supply 8A, 8B Electrostatic adsorption electrode 9A, 9B DC power supply 11 Etching gas supply device 12 Vacuum exhaust device 13 Refrigerant supply device 14 Gap 16 Heat transfer gas supply / discharge device 17 Push-up device 18 Push-up pin 19 Base 21 Cylinder 21a Rod 22 Housing 23 Holding plate (insulating plate member)
23a Upper surface 23b Lower surface 24 Electrode plate (metal plate member)
24a upper surface 24b lower surface 26 pedestal member 27, 28 frame 29 annular plate 31 upper accommodation hole (first accommodation hole)
32 hole body 32a peripheral wall 33 counterbore part 33a bottom wall 33b peripheral wall 34 projection 36 surrounding part 37 refrigerant circulation channel 38 refrigerant channel 39 lower accommodation hole (second accommodation hole)
39a Perimeter wall 41 Metal-based adhesive layer 42 Housing hole 43 Nozzle member (first gas supply member)
43a upper end surface 43b lower end surface 43c outer peripheral surface 44 upper gas supply hole (first gas supply hole)
44a Upper end opening 44b Lower end opening 46 Lower end recess 47 Inlet member (second gas supply member)
47a Upper end surface 47b Lower end surface 47c Expanded portion 47d Outer peripheral surface 48 Lower gas supply hole (second gas supply hole)
48a Upper end opening 48b Lower end opening 49 Fitting hole 49a Perimeter wall 51 Flow path member 51a Heat transfer gas flow path 52 Insulating adhesive layer 56 Heat transfer gas supply line 57 Heat transfer gas exhaust line 58 Heat transfer gas source 59 MFC
61A, 61B, 61C, 61D Cutoff valve 62 Vacuum pump 63 Automatic pressure control valve 64 Vacuum gauge 66, 67 Bypass line 68 Controller 71, 72 Site 73 Path 81 Housing hole 82 Guide cylinder member 82a Guide hole 83 Housing hole 84 Through hole

Claims (14)

An electrode (8A, 8B) made of an insulating material for electrostatically adsorbing the substrate (2) and holding it on the upper surface (23a) is disposed inside, and the first penetrates from the upper surface to the lower surface (23b). An insulating plate member (23) in which a receiving hole (31) is formed;
The insulating plate member is made of a metal material, the insulating plate member is fixed to the upper surface (24a), and the second receiving hole (39) having a hole size larger than the first receiving hole penetrating from the upper surface to the lower surface (24b) is the insulating material. A metal plate member (24) formed at a position corresponding to the first accommodation hole of the plate member and to which a high-frequency voltage for plasma generation is applied;
A plurality of first gas supply holes (44) made of an insulating material, accommodated in the first accommodation hole of the insulating plate member, and penetrating from the upper end surface (43a) to the lower end surface (43b) are formed, And a first gas supply member (43) in which an upper end opening (44a) of the first gas supply hole is opened on the upper surface of the insulating plate member;
A second gas supply hole (48) made of an insulating material and accommodated in the second accommodation hole of the metal plate member and having a hole size larger than the first gas supply hole is formed from the upper end surface (47a). It is formed to penetrate to the lower end surface (47b), heat transfer gas is supplied from the lower end opening (48b) of the second gas supply hole, and the heat transfer gas is opened at the upper end of the second gas supply hole (48a) flows into the lower end opening (44b) of the first gas supply hole, and the gap (14 between the upper end opening of the first gas supply hole and the upper surface of the insulating plate member and the lower surface of the substrate). A second gas supply member (47),
A plasma processing apparatus comprising: an insulating adhesive layer (52) formed at least between an upper end surface of the second gas supply member and a lower surface of the insulating plate member. The hole size of the first gas supply hole is not less than 50 μm and not more than 300 μm,
2. The plasma processing apparatus according to claim 1, wherein a hole size of the second gas supply hole is 300 μm or more and 700 μm or less.   The plasma processing apparatus according to claim 1, wherein 30 or more of the first gas supply holes are provided in the first gas supply member.   The metal-based adhesive layer (41) for fixing the insulating plate member and the metal plate member to each other is further provided between the lower surface of the insulating plate member and the upper surface of the metal plate member. The plasma processing apparatus according to claim 3. The first accommodation hole is disposed on the upper surface side of the insulating plate member, has a hole size corresponding to that of the first gas supply member, and accommodates at least the upper end surface side of the first gas supply member. A hole body (32) to be formed, disposed on the lower surface side of the insulating plate member, having a hole diameter corresponding to the second gas supply member, and accommodating the upper end surface side of the second gas supply member. A counterbore part (33), and the insulating adhesive layer includes a gap between an upper end surface of the second gas supply member and a bottom wall (33a) of the counterbore part, The gap between the outer peripheral surface (47d) on the upper end surface side of the gas supply member and the peripheral wall (33b) of the spot facing portion, the outer peripheral surface on the upper end surface side of the second gas supply member, and the second housing 2. A space between the peripheral wall (39a) of the hole and formed in a gap. 5. The plasma processing apparatus according to any one of 4 above.   The said 2nd gas supply member has a fitting hole (49) in the upper end surface, and the lower end surface side of the said 1st gas supply member is engage | inserted by the said fitting hole, The characterized by the above-mentioned. The plasma processing apparatus according to any one of claims 1 to 5. An electrode (8A, 8B) made of an insulating material for electrostatically adsorbing the substrate (2) and holding it on the upper surface (23a) is disposed inside, and the first penetrates from the upper surface to the lower surface (23b). The first accommodation hole is formed with a hole body (32) disposed on the upper surface side of the insulating plate member and the hole body disposed on the lower surface side of the insulation plate member. An insulating plate member (23) comprising a counterbore (33) having a large hole size;
A second housing hole (39) made of a metal material, the insulating plate member being fixed to the upper surface (24a), and penetrating from the upper surface to the lower surface (24b) is formed with the first housing hole of the insulating plate member. A metal plate member (24) formed at a corresponding position and to which a high-frequency voltage for plasma generation is applied;
A plurality of first gas supplies made of an insulating material, the upper end surface (43a) side being accommodated in the hole body of the first accommodation hole of the insulating plate member, and penetrating from the upper end surface to the lower end surface (43b) A first gas supply member (43) in which a hole (44) is formed and an upper end opening (44a) of the first gas supply hole (44) is opened on the upper surface of the insulating plate member;
It is made of an insulating material, has an outer dimension larger than that of the first gas supply member, is accommodated in the second accommodation hole of the metal plate member, and an upper end surface (47a) side is the first of the insulation plate member. A fitting hole (49) is formed which is accommodated in the counterbore portion of the one accommodation hole and into which the lower end surface side of the first gas supply member is fitted on the upper end surface, and is more hole than the first gas supply hole. A second gas supply hole (48) having a large size is formed so as to penetrate from the upper end surface to the lower end surface (47b), and heat transfer gas is supplied from the lower end opening (48b) of the second gas supply hole. The heat transfer gas flows from the upper end opening (48a) of the second gas supply hole into the lower end opening (44b) of the first gas supply hole and from the upper end opening of the first gas supply hole. A gap between the upper surface of the insulating plate member and the lower surface of the substrate ( 4) is supplied to the second gas supply member and (47),
At least between the upper end surface of the second gas supply member and the bottom wall (33a) of the countersunk portion of the first accommodation hole, the outer peripheral surface (47d) of the second gas supply member and the first accommodation. An insulating adhesive layer (52) formed between the peripheral wall (33b) of the counterbore part of the hole and between the outer peripheral surface of the second gas supply member and the peripheral wall of the second accommodation hole. A plasma processing apparatus comprising: The hole size of the first gas supply hole is not less than 50 μm and not more than 300 μm,
The plasma processing apparatus according to claim 7, wherein a hole size of the second gas supply hole is 300 μm or more and 700 μm or less.   9. The plasma processing apparatus according to claim 7, wherein the first gas supply member is provided with 30 or more first gas supply holes.   The metal-based adhesive layer (41) for fixing the insulating plate member and the metal plate member to each other is further provided between the lower surface of the insulating plate member and the upper surface of the metal plate member. The plasma processing apparatus according to claim 9. An electrode (8A, 8B) made of an insulating material for electrostatically adsorbing the substrate (2) and holding it on the upper surface (23a) is disposed inside, and the first penetrates from the upper surface to the lower surface (23b). An insulating plate member (23) in which a receiving hole (31) is formed;
The insulating plate member is made of a metal material, fixed to the upper surface (24a), and the second receiving hole (39) having the same hole size as the first receiving hole is formed with the first receiving hole of the insulating plate member. A metal plate member (24) formed so as to penetrate from the upper surface to the lower surface (24b) at a corresponding position and to which a high-frequency voltage for plasma generation is applied;
A plurality of first gas supply holes (44) made of an insulating material and housed in the first housing hole of the insulating plate member and penetrating from the upper end surface (43a) to the lower end surface (43b) are formed. And a first gas supply member (43) in which an upper end opening (44a) of the first gas supply hole is opened on the upper surface of the insulating plate member;
The first gas supply is made of an insulating material and accommodated in the second accommodation hole of the metal plate member, and the upper end surface (47a) side is accommodated in the first accommodation hole of the insulation plate member. A second gas supply hole (48) having a hole size larger than the hole is formed so as to penetrate from the upper end surface to the lower end surface (47b), and heat is transferred from the lower end opening (48b) of the second gas supply hole. Gas is supplied, and the heat transfer gas flows from the upper end opening (48a) of the second gas supply hole into the lower end opening (44b) of the first gas supply hole and passes through the first gas supply hole. A second gas supply member (47) having the same outer dimensions as the first gas supply member, which is supplied from the upper end opening to a gap (14) between the upper surface of the insulating plate member and the lower surface of the substrate; ,
At least a gap between the outer peripheral surface (43c) of the first gas supply member and the peripheral wall (32a) of the first accommodation hole, the outer peripheral surface (47d) of the second gas supply member and the first accommodation. A gap between the peripheral walls of the holes, and an insulating adhesive layer (52) formed in the gap between the outer peripheral surface of the second gas supply member and the peripheral wall (39a) of the second accommodation hole. A plasma processing apparatus. The hole size of the first gas supply hole is not less than 50 μm and not more than 300 μm,
The plasma processing apparatus according to claim 11, wherein a hole size of the second gas supply hole is not less than 300 μm and not more than 700 μm.   The plasma processing apparatus according to claim 11, wherein the first gas supply member is provided with 30 or more first gas supply holes.   The metal-based adhesive layer (41) for fixing the insulating plate member and the metal plate member to each other is further provided between the lower surface of the insulating plate member and the upper surface of the metal plate member. The plasma processing apparatus according to claim 1.

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