JP4783440B2 - Plasma processing apparatus and plasma processing method - Google Patents

Description

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

  Patent Document 1 discloses a plasma processing apparatus having a configuration in which a bottomed tray containing a substrate is disposed on a substrate susceptor that functions as a lower electrode, and the substrate is indirectly electrostatically attracted to the substrate susceptor via the tray. Is disclosed. A substrate susceptor cooling mechanism is provided, and the substrate is cooled by indirect heat conduction with the substrate susceptor via the tray.

  In Patent Document 2, a bottomed tray containing a substrate is arranged on a substrate susceptor, and the vicinity of the outer periphery of the substrate is pressed against the substrate susceptor side by a clamp ring, thereby fixing the substrate to the substrate susceptor. A plasma processing apparatus is disclosed. A flow path that penetrates the tray and reaches the lower surface of the substrate is provided, and the back surface of the substrate is cooled by the cooling gas supplied through the flow path.

  However, in the plasma processing apparatus described in Patent Document 1, the substrate is electrostatically attracted to the substrate susceptor indirectly via the tray, and is cooled by indirect heat conduction with the substrate susceptor via the tray. Therefore, the substrate cannot be cooled efficiently.

  On the other hand, in the plasma processing apparatus described in Patent Document 2, there is a tendency that the state of plasma is particularly uneasy near the outer peripheral edge of the substrate where the clamp ring exists, and the processing is made uniform between the central portion and the outer peripheral edge of the substrate. Can not. For example, in the case of dry etching, an etching pattern cannot be formed near the outer periphery of the substrate where the clamp ring exists.

  Furthermore, in the plasma processing apparatuses of the type in which conventionally proposed trays containing substrates, including those disclosed in Patent Documents 1 and 2, are arranged on the substrate susceptor, sufficient consideration is given to the positioning accuracy of the substrate with respect to the substrate susceptor. Not done. However, the substrate positioning accuracy with respect to the substrate susceptor is particularly important in realizing batch processing of a plurality of substrates accommodated in one tray.

JP 2000-58514 A JP 2003-197607 A

  The present invention relates to a plasma processing apparatus in which a tray containing a substrate is disposed on a substrate susceptor, thereby improving the cooling efficiency of the substrate by holding the substrate with high adhesion to the substrate susceptor, and the substrate surface including the vicinity of the outer periphery. It is an object of the present invention to make the processing uniform in all the regions and improve the positioning accuracy of the substrate with respect to the substrate susceptor.

The first invention is provided with a chamber (3) capable of depressurization and a plurality of substrate accommodation holes (19, 19A to 19I) each accommodating a substrate (2), and a hole wall (15d) of the substrate accommodation hole. A tray (15) provided with a substrate support (21) protruding from the tray, which can be carried into and out of the chamber, and provided in the chamber, protruding upward from the tray support (28), and A dielectric member (23) comprising a plurality of substrate placement portions (29, 29A to 29D) on which the lower surface of the substrate is respectively placed on a substrate placement surface (31) which is an upper end surface thereof, and the substrate An electrostatic chucking electrode (40, 40A, 40B) for electrostatically attracting the substrate to the substrate mounting surface, at least part of which is built in the mounting unit, and a DC voltage applied to the electrostatic chucking electrode DC voltage application mechanism (43, 3A to 43F) and a heat transfer gas supply mechanism (45, 45A to 45D) for supplying a heat transfer gas between the substrate and the substrate mounting surface, the substrate mounting surface and the substrate mounting The connecting portion of the outer peripheral surface of the portion is chamfered with a round surface, and the outer diameter increases from the substrate mounting surface side toward the tray support portion side, and the tip end surface (21b) of the substrate support portion of the tray is It is a tapered surface in which the amount of protrusion from the hole wall increases from the lower surface (15c) side to the upper surface (15b) side of the tray, and when the substrate is transported, the lower surface of the substrate accommodated in the substrate accommodation hole The substrate mounting portion is supported by the substrate support portion, and when the substrate is processed, the substrate mounting portion is inserted into the substrate receiving hole configured so that the substrate mounting surface enters in the thickness direction of the tray. is inserted from the lower side of the tray, the tip of the substrate supporting portion There are guided by the connecting portion of the outer peripheral surface of the substrate mounting portion and the substrate mounting surface, the lower surface of the tray is placed on the tray support portion of said dielectric member, characterized in that A plasma processing apparatus is provided. A gap between the outer peripheral surface of the substrate mounting portion and the tip end surface of the substrate supporting portion in a state where the tray is mounted on the tray support is about 0.5 mm.

  The lower surface of the substrate is placed directly on the dielectric member without going through the tray. Specifically, the substrate placement portion of the dielectric member is inserted into the substrate accommodation hole from the lower surface side of the tray, and the substrate is placed on the substrate placement surface which is the upper end surface of the substrate placement portion. Therefore, when a DC voltage is applied to the electrostatic chucking electrode from the DC voltage application mechanism, the substrate is held with high adhesion to the substrate mounting surface. As a result, the thermal conductivity between the substrate and the substrate mounting surface through the heat transfer gas is good, the substrate can be cooled with high cooling efficiency, and the substrate temperature can be controlled with high accuracy.

  Since the substrate is directly mounted on the substrate mounting surface and is electrostatically attracted, a member such as a clamp ring for mechanically pressing the outer peripheral edge portion of the upper surface of the substrate against the dielectric member is unnecessary. . In other words, there is no member on the upper surface of the substrate to be subjected to plasma processing that causes the plasma state to become unstable not only in the central portion but also in the vicinity of the outer peripheral edge. Therefore, uniform plasma processing can be realized in the entire region of the substrate surface including the vicinity of the outer periphery.

  The substrate is placed on the substrate placement surface by the substrate placement portion entering the substrate accommodation hole of the tray. Accordingly, the substrate can be held on the substrate mounting surface with high positioning accuracy.

  In addition, since the outer diameter of the connecting portion between the substrate mounting surface and its outer peripheral surface as viewed from the through direction of the substrate receiving hole of the tray increases from the substrate mounting surface side to the tray supporting portion side, Even when the substrate receiving hole and the substrate mounting portion have a slight shift in the position in plan view, the substrate mounting portion is smoothly and reliably inserted into the substrate receiving hole. Also in this respect, the substrate is placed with high positioning accuracy with respect to the substrate placement surface.

  Preferably, the tray has an inner diameter of the substrate accommodation hole as viewed from a penetration direction of the substrate accommodation hole of the tray at a connection portion between a hole wall of the substrate accommodation hole and a lower surface of the tray. It decreases from the lower surface side toward the upper surface side of the tray. With this configuration, the substrate mounting portion can be more reliably and smoothly inserted into the substrate accommodation hole.

A second invention is the substrate (2) a plurality of substrate accommodation hole (19,19A～19I) is provided to be respectively accommodated, the substrate support portion protruding from the substrate accommodation hole hole wall (15d) (21) A tray (15) capable of transporting the substrate, wherein a tip end surface of the substrate support portion has a protruding amount from the hole wall increasing from a lower surface side to an upper surface side of the tray . Prepared and disposed in a chamber (3) capable of depressurization, comprising a tray support portion (28) and a plurality of substrate placement portions (29A to 29D) protruding upward from the tray support portion; connecting portions between the outer peripheral surface of the substrate platform and the substrate mounting surface which is the upper end surface of the portion outside diameter are chamfered into a round surface increases toward the tray support portion from the substrate support surface, In addition, the electrostatic chucking electrodes (40A, 40B) have a small number of the substrate mounting portions. Also prepare a dielectric member (23) which has a built-in part and the substrate (2) to the substrate accommodation hole of the tray accommodating respectively, the outer peripheral edge portion of the lower surface (2a) of the substrate by the substrate supporting portion In a state where the tray is supported, the tray is carried into the chamber,
The tray is disposed above the dielectric member, the tray is lowered toward the dielectric member, and the substrate placement portions (29A to 29D) enter the substrate accommodation holes from the lower surface side of the tray, respectively. Guiding the front end surface of the substrate support portion at the connection portion between the substrate placement surface and the outer peripheral surface, placing the lower surface of the tray on the tray support portion (28) of the dielectric member, The lower surface (2a) of the substrate is lifted by the substrate mounting surface of the substrate mounting portion that has entered the substrate receiving hole, and is disposed above the upper surface (21a) of the substrate supporting portion of the tray with a gap. As described above, the substrate is placed on the substrate placement surface, and a DC voltage is applied to the electrostatic chucking electrode (40) that is at least partially built in the substrate placement portion, so that the substrate placement is performed. The substrate is electrostatically adsorbed on a mounting surface, and the individual substrate The heat transfer gas is supplied to the surface and a space surrounded by the annular projection of each of said substrate platform, to generate plasma in the chamber, to provide a plasma processing method.

  According to the plasma processing apparatus and the plasma processing method according to the present invention, the substrate is directly placed on the substrate placement surface of the dielectric member without passing through the tray, and is electrostatically adsorbed. The substrate can be held with high adhesion, the cooling efficiency of the substrate can be improved, and the substrate temperature can be controlled with high accuracy. In addition, since a member such as a clamp ring for mechanically pressing the outer peripheral edge portion of the upper surface of the substrate against the dielectric member is unnecessary, uniform plasma processing in the entire area of the substrate surface including the vicinity of the outer peripheral edge. Can be realized. Further, since the substrate is placed on the substrate placement surface by inserting the substrate placement portion into the substrate accommodation hole of the tray, the positioning accuracy of the substrate with respect to the dielectric member can be improved. Furthermore, since the outer diameter seen from the through direction of the substrate accommodation hole of the tray increases from the substrate placement surface side to the tray support portion side at the connection portion between the substrate placement surface and its outer peripheral surface, Even if there is a minute shift between the substrate accommodation hole and the substrate placement portion in plan view, the substrate placement portion is smoothly and reliably inserted into the substrate accommodation hole. Also in this respect, the substrate is placed with high positioning accuracy with respect to the substrate placement surface.

(First embodiment)
1 and 2 show an ICP (inductively coupled plasma) type dry etching apparatus 1 according to a first embodiment of the present invention.

  The dry etching apparatus 1 includes a chamber (vacuum container) 3 that constitutes a processing chamber in which plasma processing is performed on the substrate 2. The upper end opening of the chamber 3 is closed in a sealed state by a top plate 4 made of a dielectric material such as quartz. An ICP coil 5 is disposed on the top plate 4. A high frequency power source 7 is electrically connected to the ICP coil 5 via a matching circuit 6. A substrate susceptor 9 having a function as a lower electrode to which a bias voltage is applied and a function as a holding table for the substrate 2 is disposed on the bottom side in the chamber 3 facing the top plate 4. The chamber 3 is provided with a loading / unloading gate 3a that can be opened and closed and communicates with an adjacent load dock chamber 10 (see FIG. 2). An etching gas supply source 12 is connected to the etching gas supply port 3 b provided in the chamber 3. The etching gas supply source 12 includes an MFC (mass flow controller) or the like, and can supply an etching gas at a desired flow rate from the etching gas supply port 3b. Further, a vacuum exhaust device 13 including a vacuum pump or the like is connected to the exhaust port 3 c provided in the chamber 3.

  In this embodiment, four substrates 2 are accommodated in one tray 15 shown in FIGS. 3 to 4B, and the tray 15 is carried into the chamber 3 (processing chamber) from the load dock chamber 10 through the gate 3a. The Referring to FIG. 2, there is provided a transfer arm 16 that can move in a horizontal direction (see arrow A) and rotate in a horizontal plane (see arrow B). In the chamber 3, lift pins 18 that pass through the substrate susceptor 9 and are driven by a drive device 17 to move up and down are provided. When the tray 15 is carried in, the transfer arm 16 that supports the tray 15 enters the chamber 3 from the load dock chamber 10 through the gate 3a. At this time, as shown by a two-dot chain line in FIG. 1, the lifting pins 18 are in the raised position, and the tray 15 is transferred from the transfer arm 16 that has entered the chamber 3 to the upper end of the lifting pins 18. In this state, the tray 15 is positioned above the substrate susceptor 9 with a gap. Subsequently, the elevating pins 18 are lowered to the lowered position indicated by the solid line in FIG. 1, whereby the tray 15 and the substrate 2 are placed on the substrate susceptor 9. On the other hand, when the tray 15 is unloaded after the plasma processing, the elevating pins 18 are raised to the raised position, and then the tray 15 is transferred from the load dock chamber 10 to the transfer arm 16 that has entered the chamber 3.

Next, the tray 15 will be described with reference to FIGS. 3 to 5B. The tray 15 includes a thin disc-shaped tray body 15a. Examples of the material of the tray 15 include ceramic materials such as alumina (Al ₂ O ₃ ), aluminum nitride (AlN), zirconia (ZrO), yttria (Y ₂ O ₃ ), silicon nitride (SiN), and silicon carbide (SiC). There are also metals such as aluminum coated with alumite, aluminum coated with ceramics on the surface, and aluminum coated with a resin material. It is conceivable to employ alumina, yttria, silicon carbide, aluminum nitride or the like in the case of a Cl-based process, and aluminum or the like which applies quartz, quartz, yttria, silicon carbide, anodized or the like in the case of an F-based process.

  The tray body 15a is provided with four substrate accommodation holes 19A to 19D that penetrate in the thickness direction from the upper surface 15b to the lower surface 15c. The substrate accommodation holes 19A to 19D are arranged at equiangular intervals with respect to the center of the tray body 15a when viewed from the upper surface 15b and the lower surface 15c. As shown most clearly in FIGS. 5A and 5B, a substrate support portion 21 that protrudes toward the center of the substrate accommodation holes 19A to 19D is provided on the lower surface 15c side of the hole wall 15d of the substrate accommodation holes 19A to 19D. ing. In this embodiment, the board | substrate support part 21 is provided in the perimeter of the hole wall 15d, and is annular | circular shape by planar view.

  One substrate 2 is accommodated in each of the substrate accommodation holes 19A to 19B. As shown in FIG. 5A, the outer peripheral edge portion of the lower surface 2 a of the substrate 2 accommodated in the substrate accommodation holes 19 </ b> A to 19 </ b> B is supported by the upper surface 21 a of the substrate support portion 21. Further, as described above, the substrate accommodation holes 19A to 19D are formed so as to penetrate the tray main body 15a in the thickness direction. The lower surface 2a is exposed.

  The tray body 15a is provided with a positioning cutout 15e in which the outer peripheral edge is partially cut out. As shown in FIG. 2, when the tray is placed on the carry-in / out carrying arm 16, the positioning protrusion 16a of the carrying arm 16 is fitted into the positioning notch 15e. By detecting the positioning notches 15e and the positioning protrusions 16a with the sensors 22A and 22B provided in the load dock chamber 10, the rotational angle position of the tray 15 can be detected.

  Next, the substrate susceptor 9 will be described with reference to FIGS. 1, 3, and 5A to 6B. First, referring to FIG. 1, the substrate susceptor 9 is made of a dielectric plate (dielectric member) 23 made of ceramics or the like, aluminum having an alumite coating on the surface, etc., and in this embodiment, a metal plate that functions as a pedestal electrode (Support member) 24, a spacer plate 25 made of ceramics or the like, a guide cylinder 26 made of ceramics or the like, and a metal earth shield 27 are provided. The dielectric plate 23 constituting the uppermost part of the substrate susceptor 9 is fixed to the upper surface of the metal plate 24. The metal plate 24 is fixed on the spacer plate 25. Further, the guide cylinder 26 covers the outer periphery of the dielectric plate 23 and the metal plate 24, and the earth shield 27 covers the outer periphery thereof and the outer periphery of the spacer plate 25.

  Referring to FIGS. 3 and 5A to 6B, the dielectric plate 23 has a thin disk shape as a whole and has a circular outer shape in plan view. The upper end surface of the dielectric plate 23 constitutes a tray support surface (tray support portion) 28 that supports the lower surface 15 c of the tray 15. Further, four short columnar substrate placement portions 29A to 29D respectively corresponding to the substrate accommodation holes 19A to 19D of the tray 15 protrude upward from the tray support surface 28.

  The upper end surfaces of the substrate placement portions 29A to 29D constitute a substrate placement surface 31 on which the lower surface 2a of the substrate 2 is placed. Further, the substrate placement portions 29 </ b> A to 29 </ b> D are provided with an annular protrusion 32 that protrudes upward from the outer peripheral edge of the substrate placement surface 31 and whose upper end surface supports the lower surface 2 a of the substrate 2. In addition, a plurality of columnar projections 33 having a sufficiently smaller diameter than the substrate mounting surface 31 are provided in a portion surrounded by the annular protrusion 32 of the substrate mounting surface 31 so as to be uniformly distributed. . The protruding amount of the cylindrical protrusion 33 and the annular protrusion 32 from the substrate mounting surface 31 is the same, and not only the annular protrusion 32 but also the upper end surface of the cylindrical protrusion 33 supports the lower surface 2 a of the substrate 2.

  5A and 5B, the outer diameter R1 of the substrate placement portions 29A to 29D is set to be smaller than the diameter R2 of the circular opening 36 surrounded by the front end surface 21b of the substrate support portion 21. Accordingly, when the tray 15 is lowered toward the dielectric plate 23 at the time of carrying in, the individual substrate placement portions 29A to 29D enter the corresponding substrate accommodation holes 19A to 19D from the lower surface 15c side of the tray main body 15a, and the tray. The lower surface 15 c of 15 is placed on the tray support surface 28 of the dielectric plate 23. Further, the height H1 of the upper surface 21a of the substrate support portion 21 from the lower surface 15c of the tray body 15a is set lower than the height H2 of the substrate placement surface 31 from the tray support surface 28. Therefore, in a state where the lower surface 15 c of the tray 15 is placed on the tray support surface 28, the tray 15 is pushed up by the substrate placement surface 31 at the upper end of the substrate placement portions 29 </ b> A to 29 </ b> D and lifts from the substrate support portion 21 of the tray 15. Yes. In other words, when the tray 15 that accommodates the substrate 2 in the substrate accommodation holes 19 </ b> A to 19 </ b> D is placed on the dielectric plate 23, the substrate 2 accommodated in the substrate accommodation holes 19 </ b> A to 19 </ b> D becomes the upper surface of the substrate support portion 21. The lower surface 2 a is placed on the substrate placement surface 31.

  Further, as shown in FIGS. 5A and 5B, the connection portion between the outer peripheral surface 38 of the substrate placement portions 29 </ b> A to 29 </ b> D and the substrate placement surface 31 is chamfered into a round surface. Therefore, on the upper end side of the substrate placement portions 29A to 29D, the outer diameter viewed from the through direction of the substrate accommodation holes 19A to 19D increases from the substrate placement surface 31 side toward the tray support surface 28. On the other hand, on the lower end side of the outer peripheral surface 38 of the substrate placement portions 29A to 29D, the outer diameter viewed from the penetration direction of the substrate accommodation holes 19A to 19D can be constant.

  Referring to FIG. 1, a monopolar electrostatic attraction electrode 40 is built in the vicinity of the substrate placement surface 31 of each of the substrate placement portions 29 </ b> A to 29 </ b> D of the dielectric plate 23. These electrostatic chucking electrodes 40 are electrically insulated from each other, and a DC voltage for electrostatic chucking is applied from a common DC voltage applying mechanism 43 including a DC power supply 41 and an adjusting resistor 42.

  Referring to FIGS. 3, 6A, and 6B, the substrate placement surface 31 of each of the substrate placement portions 29A to 29D is provided with a supply hole 44 for heat transfer gas (helium in the present embodiment). . These supply holes 44 are connected to a common heat transfer gas supply mechanism 45 (shown in FIG. 1). The heat transfer gas supply mechanism 45 includes a heat transfer gas source (in this embodiment, a helium gas source) 46, a supply channel 47 from the heat transfer gas source 46 to the supply hole 44, and a heat transfer gas source 46 in the supply channel 47. A flow meter 48, a flow control valve 49, and a pressure gauge 50 are provided in this order from the side. The heat transfer gas supply mechanism 45 includes a discharge flow channel 51 that branches from the supply flow channel 47 and a cut-off valve 52 provided in the discharge flow channel 51. Furthermore, the heat transfer gas supply mechanism 45 includes a bypass channel 53 that connects the supply channel 44 side to the discharge channel 51 with respect to the pressure gauge 50 of the supply channel 47. Between the substrate placement surface 31 of each of the substrate placement portions 29A to 29D and the lower surface 2a of the substrate 2 placed thereon, in detail, it is surrounded by the lower surface 2a of the substrate 2 and the annular protrusion 32. The heat transfer gas is supplied to the closed space by the heat transfer gas supply mechanism 45. When supplying the heat transfer gas, the cutoff valve 52 is closed, and the heat transfer gas is sent from the heat transfer gas supply source 46 to the supply hole 44 through the supply path 47. Based on the flow rate and pressure of the supply flow path 47 detected by the flow meter 48 and the pressure gauge 50, the controller 63 described later controls the flow rate control valve 49. On the other hand, when the heat transfer gas is discharged, the cut-off valve 52 is opened, and the heat transfer gas between the lower surface 2a of the substrate 2 and the substrate placement surface 31 passes through the supply hole 44, the supply flow path 47, and the discharge flow path 51. Then, the air is exhausted from the exhaust port 54.

  A high frequency applying mechanism 56 that applies a high frequency as a bias voltage is electrically connected to the metal plate 24. The high frequency applying mechanism 56 includes a high frequency power source 57 and a matching variable capacitor 58.

  Further, a cooling mechanism 59 for cooling the metal plate 24 is provided. The cooling mechanism 59 includes a refrigerant flow path 60 formed in the metal plate 24 and a refrigerant circulation device 61 that circulates the temperature-controlled refrigerant in the refrigerant flow path 60.

  The controller 63 schematically shown only in FIG. 1 is based on various sensors and operation inputs including a flow meter 48 and a pressure gauge 50, and a high-frequency power source 7, an etching gas supply source 12, a transfer arm 16, a vacuum exhaust device 13, The operation of the entire dry etching apparatus 1 including the drive device 17, the DC voltage application mechanism 43, the heat transfer gas supply mechanism 45, the high frequency voltage application mechanism 56, and the cooling mechanism 59 is controlled.

  Next, a dry etching method using the dry etching apparatus 1 of the present embodiment will be described.

  First, the board | substrate 2 is accommodated in the board | substrate accommodation holes 19A-19D of the tray 1, respectively. The substrate 2 supported by the substrate support portion 21a of the tray 1 is exposed from the lower surface 15c of the tray body 15a through the substrate housing holes 19A to 19D when viewed from the lower surface side of the tray body 15a.

  Next, the tray 15 that accommodates the substrate 2 in each of the substrate accommodation holes 19A to 19D is supported by the transfer arm 16, and is carried into the chamber 3 from the load dock chamber 10 through the gate 3a. As shown by a two-dot chain line in FIG. 1, the tray 1 is disposed above the substrate susceptor 9 with a gap.

  The elevating pins 18 driven by the driving device 7 are raised, and the tray 15 is transferred from the transfer arm 16 to the upper end of the elevating pins 18. After the transfer of the tray 15, the transfer arm 16 is retracted to the load lock chamber 10, and the gate 3a is closed.

  The raising / lowering pins 18 that support the tray 15 at the upper end are lowered toward the substrate susceptor 9 from the raised position indicated by a two-dot chain line in FIG. 5A and 5B, the lower surface 15c of the tray 15 is lowered to the tray support surface 28 of the dielectric plate 23 of the substrate susceptor 9, and the tray 15 is supported by the tray support surface 28 of the dielectric plate 23. When the tray 15 descends toward the tray support surface 28, the substrate placement portions 29A to 29D of the dielectric plate 23 enter the corresponding substrate accommodation holes 19A to 19D of the tray 15 from the lower surface 15c side of the tray 15. . As the lower surface 15c of the tray 15 approaches the tray support surface 28, the substrate placement surface 31 at the tip of the substrate placement portions 29A to 29D advances in the substrate accommodation holes 19A to 19D toward the upper surface 15b of the tray 15. As shown in FIG. 5B, when the lower surface 15c of the tray 15 is placed on the tray support surface 28 of the dielectric plate 23, the substrates 2 in the individual substrate accommodation holes 19A to 19D are moved by the substrate placement portions 29A to 29D. It is lifted from the upper surface 21 a of the substrate support portion 21. Specifically, the lower surface 2a of the substrate 2 is placed on the substrate placement surface 31 of the substrate placement portions 29A to 29D, and is disposed above the upper surface 21a of the substrate support portion 21 of the tray 15 with a gap. The

  As described above, the substrate placement portions 29A to 29D enter the substrate accommodation holes 19A to 19D of the tray 15, so that the substrate 2 is placed on the substrate placement surface 31. Accordingly, the four substrates 2 accommodated in the tray 15 are all placed on the substrate placement surfaces 31 of the substrate placement portions 29A to 29D with high positioning accuracy. Further, as described above, since the connection portion between the outer peripheral surface 38 of the substrate placement portions 29A to 29D and the substrate placement surface 31 is chamfered into a round surface, the substrate accommodation holes 19A to 19D and the substrate placement portion 29A are temporarily assumed. Even when there is a minute shift in the position in plan view of .about.29D, the chamfered portions of the substrate mounting portions 29A to 29D are in contact with the front end surface 21b of the substrate support portion 21. FIG. As a result, the substrate platforms 29A to 29D are smoothly and reliably inserted into the substrate accommodation holes 19A to 19D. Also in this respect, the substrate 2 is placed with high positioning accuracy with respect to the substrate placement surface 31.

  Next, a DC voltage is applied from the DC voltage application mechanism 43 to the electrostatic attraction electrode 40 built in the dielectric plate 23, and the substrate 2 is applied to the substrate placement surfaces 31 of the individual substrate placement portions 29 </ b> A to 29 </ b> D. Is electrostatically adsorbed. The lower surface 2 a of the substrate 2 is directly placed on the substrate placement surface 31 without using the tray 15. Accordingly, the substrate 2 is held with a high degree of adhesion to the substrate placement surface 31.

  Subsequently, the heat transfer gas is supplied from the heat transfer gas supply device 45 through the supply hole 44 to the space surrounded by the annular protrusions 32 of the individual substrate placement portions 29 </ b> A to 29 </ b> D and the lower surface 2 a of the substrate 2. This space is filled with heat transfer gas.

  Thereafter, an etching gas is supplied from the etching gas supply source 12 into the chamber 3, and the inside of the chamber 3 is maintained at a predetermined pressure by the vacuum exhaust device 13. Subsequently, a high frequency voltage is applied from the high frequency power supply 7 to the ICP coil 5, and a bias voltage is applied to the metal plate 24 of the substrate susceptor 9 by the high frequency application mechanism 56 to generate plasma in the chamber 3. The substrate 2 is etched by this plasma. Since four substrates 2 can be placed on the substrate susceptor 9 with one tray 15, batch processing is possible.

  During the etching, the refrigerant is circulated in the refrigerant flow path 60 by the refrigerant circulation device 61 to cool the metal plate 24, thereby the substrate 2 held on the dielectric plate 23 and the substrate mounting surface 31 of the dielectric plate 23. Cool down. As described above, the lower surface 2a of the substrate 2 is directly placed on the substrate placement surface 31 without the tray 15 and is held with a high degree of adhesion. Therefore, the sealing degree of the space filled with the heat transfer gas surrounded by the annular protrusion 32 and the lower surface 2a of the substrate 2 is high, and the space between the substrate 2 and the substrate placement surface 31 through the heat transfer gas is high. Good thermal conductivity. As a result, the substrate 2 held on the substrate placement surfaces 31 of the individual substrate placement units 29A to 29D can be cooled with high cooling efficiency, and the temperature of the substrate 2 can be controlled with high accuracy. In addition, a heat transfer gas is filled in the space surrounded by the annular protrusion 32 and the lower surface 2a of the substrate placement portions 29A to 29D for each individual substrate 2. In other words, the space filled with the heat transfer gas is different for each substrate 2. Also in this respect, the thermal conductivity between the individual substrates 2 and the substrate mounting surface 31 of the dielectric plate 23 is good, and high cooling efficiency and high-accuracy temperature control can be realized.

  As described above, since the substrate 2 is directly placed on the substrate placement surfaces 31 of the individual substrate placement portions 29A to 29D and is electrostatically attracted, the degree of adhesion to the substrate placement surface 31 is high. Therefore, a member such as a clamp ring for mechanically heating the outer peripheral edge portion of the upper surface of the substrate 2 with respect to the dielectric plate 23 is unnecessary. In other words, there is no member on the upper surface of the substrate 2 that causes the plasma state to become unstable not only in the central portion but also in the vicinity of the outer periphery. Therefore, uniform plasma processing can be realized in the entire region of the surface of the substrate 2 including the vicinity of the outer peripheral edge.

  In order to prevent the plasma from flowing to the lower surface 2a side of the substrate 2 during the etching process while ensuring the positioning accuracy of the substrate 2 with respect to the substrate mounting surface 31, the outer peripheral edge of the substrate 2 and the substrate accommodation hole of the tray 15 are used. The gap δ1 between the hole walls 15d of 19A to 19D is about 0.1 to 0.2 mm, and the gap δ2 between the lower surface 2a of the substrate 2 and the upper surface 21a of the substrate support portion 21 of the tray 15 is 0.2 to It is preferable that the gap δ3 between the side walls of the substrate placement portions 29A to 29D and the tip of the substrate support portion 21 is about 0.5 mm.

  After the etching is finished, the application of the high frequency voltage from the high frequency power source 7 to the ICP coil 5 and the application of the bias voltage from the high frequency application mechanism 56 to the metal plate 24 are stopped. Subsequently, the etching gas is exhausted from the chamber 3 by the vacuum exhaust device 13. Further, the heat transfer gas is exhausted from the substrate placement surface 31 and the lower surface 2 a of the substrate 2 by the heat transfer gas supply mechanism 45. Further, the application of the DC voltage from the DC voltage application mechanism 43 to the electrostatic chucking electrode 40 is stopped to release the electrostatic chucking of the substrate 2.

  Next, the elevating pins 18 are raised by the driving device 17. When the elevating pin 18 is raised, the lower surface 15c of the tray 15 is pushed up at the upper end of the elevating pin 18 and is lifted from the tray support surface 28 of the dielectric plate 23. When the toilet 15 is further lifted together with the lift pins 18, the lower surface 2c of the substrate 2 is pushed up by the substrate support portion 21 of the tray 15 as shown in FIG. From 31 The raising / lowering pin 18 rises to a raised position indicated by a two-dot chain line in FIG.

  Thereafter, the tray 15 is transferred to the transfer arm 16 that has entered the chamber 3 from the load dock chamber 10 through the gate 3a. The tray 15 is carried out to the load dock chamber 10 by the transfer arm 16.

  7 to 10 show various alternatives relating to the substrate support portion 21 of the tray 15 and the substrate placement portion 4 of the dielectric plate 23.

  In the example of FIG. 7, the connection portion between the outer peripheral surface 38 of the substrate placement portions 29 </ b> A to 29 </ b> D and the substrate placement surface 31 is not only chamfered into a round surface, but also the front end surface 21 b of the substrate support portion 21 of the tray 15. Is a tapered surface in which the amount of protrusion from the hole wall 15d increases from the lower surface 15c side of the tray 15 toward the upper surface 15b side. If the front end surface 21b of the substrate support portion 21 is such a tapered surface, the substrate mounting portion 19A to 19D and the substrate placement portions 29A to 29D can be mounted on the substrate even when there is a slight shift in the plan view. The placement portions 29A to 29D can be more reliably and smoothly inserted into the substrate housing holes 19A to 19D.

  In the example of FIG. 8, the outer peripheral surfaces 38 of the substrate placement portions 29 </ b> A to 29 </ b> D are tapered surfaces whose outer diameter increases from the substrate placement surface 31 toward the tray support portion 21. Further, the front end surface 21b of the substrate support portion 21 of the tray 15 is a tapered surface in which the protruding amount from the hole wall 15d increases from the lower surface 15c side of the tray 15 toward the upper surface 15b side. As described above, even when both the outer peripheral surfaces of the substrate placement portions 29A to 29D and the front end surface 21b of the substrate support portion 21 are tapered surfaces, the substrate placement portions 29A to 29D can be more reliably and more easily configured with respect to the substrate accommodation holes 19A to 19D. Can be inserted smoothly.

  In the example of FIGS. 9 and 10, not only is the connection portion between the outer peripheral surface 38 of the substrate mounting portions 29 </ b> A to 29 </ b> D and the substrate mounting surface 31 chamfered into a round surface, but also the front end surface 21 a of the substrate support 21 is formed. The tray 15 has an arcuate surface in which the amount of protrusion from the hole wall 15d increases from the lower surface 15c side to the upper surface 15b side. In the example of FIG. 9, the radius of curvature of the arc that forms the tip surface 21a is set to be relatively large, and the height from the lower surface 21c to the upper surface 21a of the substrate support portion 21 is set to be large. On the other hand, in the example of FIG. 10, the radius of curvature of the arc constituting the tip surface 21 a is set to be relatively small, and the height of the substrate support 21 is set to be small.

  In the first embodiment (FIGS. 5A and 5B) and various alternatives shown in FIGS. 7 to 10, one or both of the front end surface 21b of the substrate support portion 21 and the outer peripheral surface 38 of the substrate placement portions 29A to 29D. The surface may be coated with a relatively hard material such as yttria. By providing such a coating, when the tray 15 is placed on the dielectric plate 23 or when the tray 15 is lowered from the dielectric plate 23, the substrate support portion 21 of the tray 15 and the substrate placement portion of the dielectric plate 23 are placed. Generation of dust due to contact with 29A to 29D can be prevented.

(Second Embodiment)
The second embodiment of the present invention shown in FIGS. 11 to 13B is different from the first embodiment in the structure of the tray 15 and the dielectric plate 23 of the substrate susceptor 9.

  On the lower surface 15c side of the hole wall 15d of each of the substrate housing holes 19A to 19D formed in the tray main body 15a, four protruding substrate support portions 21 are provided at intervals in the circumferential direction. Specifically, when viewed from the penetration direction of the substrate accommodation holes 19A to 19D, the four substrate support portions 21 are provided at equiangular excess intervals (90 ° intervals) with respect to the centers of the substrate accommodation holes 19A to 19D. . On the other hand, four receiving grooves 65 extending from the substrate mounting surface 31 toward the tray support surface 28 are formed on the outer peripheral surface 38 of each of the substrate mounting portions 29A to 29D of the dielectric plate 23. In plan view, four receiving grooves 65 are provided at equiangular intervals with respect to the centers of the individual substrate placement portions 29A to 29D. The size and shape of the receiving groove 65 in plan view are set slightly larger than the protruding substrate support 21.

  As shown in FIG. 11, if any of the substrate accommodation holes 19 </ b> A to 19 </ b> D of the tray 15 is positioned above the individual substrate placement portions 29 </ b> A to 29 </ b> D of the dielectric plate 23, the tray 15 is placed on the dielectric plate 23. When descending, the four substrate support portions 21 of the individual substrate accommodation holes 19A to 19D are fitted into the accommodation grooves 65 of the corresponding substrate placement portions 29A to 29D. Accordingly, in this case, the tray 15 can be lowered until the lower surface 15 c of the tray 15 reaches the tray support surface 28 and the lower surface 2 a of the substrate 2 is placed on the substrate placement surface 31. However, as shown by arrows C1 and C2 in FIG. 11, when the angle around the center of the tray 15 is relatively large, the positions of the substrate support portion 21 and the receiving groove 56 are shifted in plan view. The substrate support portion 21 does not fit into the accommodation groove 65 and interferes with the substrate placement portions 29A to 29D. As a result, the substrate placement portions 29A to 29D are prevented from entering the substrate accommodation holes 19A to 19D. Therefore, by providing the protruding substrate support portions 21 and the accommodation grooves 65 arranged at intervals in the circumferential direction, the positioning accuracy of the substrate 2 with respect to the substrate placement surface 31 of the dielectric plate 23 is further improved.

  Since 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.

  14 and 15 show various alternatives for the tray 15. In the example of FIG. 14, seven substrate housing holes 19 </ b> A to 19 </ b> G are formed in the tray body 15 a for housing substrates each having an orientation flat in which a part of the outer peripheral edge is cut out linearly. The hole walls 15d of the substrate housing holes 19A to 19G have the same cylindrical surface as that of the first embodiment, but a part thereof is a flat surface corresponding to the orientation flat. In the example of FIG. 15, nine substrate housing holes 19 </ b> A to 19 </ b> I for housing a rectangular substrate are formed in the tray body 15 a. 14 and 15, the shape and number of the substrate accommodation holes of the tray 15 can be variously set according to the shape and number of the substrates accommodated. In addition, the shape and number of substrate placement portions provided on the dielectric plate 23 of the substrate susceptor 9 can be variously set according to the shape and number of substrate accommodation holes.

(Third embodiment)
The third embodiment of the present invention shown in FIG. 16 includes an annular guide plate 67 for positioning the tray 15 with respect to the dielectric plate 23. The guide plate 67 is fixed to the upper surface of the guide cylinder 26 and surrounds the four substrate placement portions 29A to 29D of the dielectric plate 23. The inner peripheral surface 67a of the guide plate 67 is a tapered surface that extends from the lower surface 67b toward the upper surface 67c. The thickness of the guide plate 67 is set to be approximately the same as the thickness of the tray 15.

  Referring also to FIG. 17, in this embodiment, the outer peripheral surface 15f of the tray 15 is a tapered surface whose outer diameter increases from the lower surface 15c toward the upper surface 15b. The dimensions and shape including the taper degree of the inner peripheral surface 67a of the guide plate 67 and the outer peripheral surface 15f of the tray 15 are such that when the lower surface 15c of the tray 15 is placed on the tray support surface 28, the inner peripheral surface 67a of the guide plate 67. Thus, the outer peripheral surface 15f of the tray 15 is set so as to be positioned and guided.

  In FIG. 16, when the tray 15 is lowered toward the dielectric plate 23 from the rising position indicated by the two-dot chain line, the outer peripheral surface 15 f of the tray 15 is guided to the inner peripheral surface 67 a of the guide plate 67. The substrate placement portions 29A to 29D are inserted into the substrate accommodation holes 19A to 19F of the tray 15 so that the substrate 2 in the substrate accommodation holes 19A to 19D is positioned with respect to the substrate placement surface 31 of the dielectric plate 23. In addition, the tray 15 itself holding the substrate 2 is positioned with respect to the dielectric plate 23 by the guide plate 67. As a result, the positioning accuracy of the substrate 2 with respect to the substrate mounting surface 31 of the dielectric member 23 is further improved.

  18A and 18B show alternatives to the tray 15 and the guide plate 67. FIG. In the example of FIG. 18A, the outer peripheral surface 15f of the tray 15 is a tapered surface whose outer diameter increases from the lower surface 15c toward the upper surface 15b. However, the inner peripheral surface 67a of the guide plate 67 is a flat surface extending in the vertical direction. The connecting portion with 67b is rounded off. On the other hand, in the example of FIG. 18B, the outer peripheral surface 15f of the tray 15 is a flat surface extending in the vertical direction, the connecting portion with the lower surface 15c is chamfered to a round surface, and the inner peripheral surface 67a of the guide plate 67 is changed from the lower surface 67b to the upper surface 67a. The taper surface has an outer diameter that increases toward the surface. Even if the combination of the shapes of the outer peripheral surface 15f of the tray 15 and the inner peripheral surface 67a of the guide plate 67 shown in FIGS. 18A and 18B is employed, the positioning accuracy with respect to the dielectric plate 23 of the tray 15 can be further improved. The chamfering of the outer peripheral surface 15f of the tray 15 and the inner peripheral surface 67a of the guide plate 67 is not limited to a round surface, and may be chamfered to a square surface.

  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 illustrated in FIG. 19, the dry etching apparatus 1 includes the heat transfer gas supply mechanisms 45 </ b> A to 45 </ b> D for each of the four substrate mounting portions 29 </ b> A to 29 </ b> D included in the dielectric member 4. The heat transfer gas supply mechanisms 45 </ b> A to 45 </ b> D include a common heat transfer gas source 46. However, the supply flow path 47, the flow meter 48, the flow control valve 49, the pressure gauge 50, the discharge flow path 51, the cutoff valve 52, the bypass flow path 53, and the exhaust port 54 are individually connected to the heat transfer gas supply mechanisms 45 </ b> A to 45 </ b> A. It is provided separately for each 45D. Accordingly, each of the heat transfer gas supply mechanisms 45 </ b> A to 45 </ b> D can individually control the supply and discharge of the heat transfer gas between the substrate placement surface 31 and the substrate 2. The supply of heat transfer gas between the substrate placement surface 31 and the substrate 2 is adjusted separately for each of the four substrates 2 placed on the substrate placement surfaces 31 of the four substrate placement portions 29A to 29D. it can. As a result, the cooling efficiency of the substrate 2 and the control accuracy of the substrate temperature can be further improved, thereby improving the etching accuracy.

  Further, the dry etching apparatus 1 includes DC voltage application mechanisms 43A to 43D that can be individually controlled for each of the four electrostatic chucking electrodes 40 built in the substrate platforms 29A to 29D. Each of the DC voltage application mechanisms 43 </ b> A to 43 </ b> D includes a DC power supply 41 and an adjusting resistor 42. Since the DC voltage applied to the electrostatic attraction electrodes 40 incorporated in the individual substrate placement portions 29A to 29D can be individually controlled, the placement is performed on the substrate placement surfaces 31 of the four substrate placement portions 29A to 29D. It is possible to eliminate the variation in electrostatic attraction force between the four substrates 2 thus made uniform.

  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 dry etching apparatus 1 according to the fifth embodiment of the present invention shown in FIG. 20, the high-frequency applying mechanism 56 is not a metal plate 24 but electrostatics built in the individual substrate mounting portions 29 </ b> A to 29 </ b> D of the dielectric member 4. It is electrically connected to the adsorption electrode 40. A high frequency as a bias voltage is applied to each of the electrostatic attraction electrodes 40 by the high frequency application mechanism 56 so as to be superimposed on the electrostatic attraction DC voltage applied by the DC voltage application mechanism 43. By applying the bias voltage to the electrostatic chucking electrode 40 instead of the metal plate 27, the consumption of the tray 15 can be reduced. Further, similarly to the fourth embodiment, individually controllable heat transfer gas supply mechanisms 45A to 45D are provided for the individual substrate placement units 29A to 29D.

  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.

(Sixth embodiment)
In the dry etching apparatus 1 according to the sixth embodiment of the present invention shown in FIG. 21, a static voltage applied by the DC voltage application mechanism 43 is provided for each electrostatic attraction electrode 40 built in each of the substrate mounting portions 29A to 29D. High frequency application mechanisms 56 </ b> A to 56 </ b> D for applying a high frequency as a bias voltage are provided so as to overlap with the DC voltage for electroadsorption. Each of the high frequency application mechanisms 56A to 56D includes a high frequency power source 57 and a variable capacitor 58, and can be individually controlled. According to the characteristics of the four substrates 2 placed on the substrate placement surfaces 31 of the four substrate placement portions 29A to 29D, high frequency power applied as a bias voltage to be applied to the electrostatic chucking electrode 40 is obtained. Since the adjustment can be performed, a uniform etching process with no variation among the four substrates 2 can be realized.

  Since the other configuration and operation of the sixth 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.

(Seventh embodiment)
In the dry etching apparatus 1 according to the seventh embodiment of the present invention shown in FIG. 22, a DC voltage application mechanism 43 </ b> A that can be individually controlled for each electrostatic attraction electrode 40 built in each of the substrate mounting portions 29 </ b> A to 29 </ b> D. ˜43D. In addition, a common high-frequency application mechanism 56 is provided for applying a high frequency as a bias voltage to the electrostatic attraction electrodes 40 built in the individual substrate placement units 29A to 29D. Since the DC voltage applied to the electrostatic attraction electrodes 40 incorporated in the individual substrate placement portions 29A to 29D can be individually controlled, the placement is performed on the substrate placement surfaces 31 of the four substrate placement portions 29A to 29D. It is possible to eliminate the variation in electrostatic attraction force between the four substrates 2 thus made uniform.

  Since the other configuration and operation of the seventh 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.

(Eighth embodiment)
In the dry etching apparatus 1 according to the eighth embodiment of the present invention shown in FIG. 23, the electrostatic chucking electrode 40 is built in each of the substrate mounting portions 29A to 29D. Each of the substrate mounting portions 29A to 29D includes a bias applying electrode 68 on the metal plate 24 side (lower side in the drawing) with respect to the electrostatic attraction electrode 40. The bias application voltage 68 is electrically insulated from the electrostatic adsorption electrode 40. A high frequency as a bias voltage is applied from a common high frequency applying mechanism 56 to the bias applying electrode 68 incorporated in each of the substrate mounting portions 29A to 29D.

  A high-frequency application mechanism that can be individually controlled may be provided for each bias voltage electrode 68 of each of the substrate placement portions 29A to 29D. By individually adjusting the high frequency applied as the bias voltage for each of the bias electrodes 68 incorporated in the four substrate placement units 29A to 29D, the substrate placement surfaces 31 of the four substrate placement units 29A to 29D are adjusted. A uniform etching process with no variation among the four substrates 2 placed thereon can be realized.

  Since the other configurations and operations of the eighth 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.

(Ninth embodiment)
FIG. 24 shows a dry etching apparatus 1 according to the ninth embodiment of the present invention. As shown in FIGS. 25 to 26B, the tray 15 is formed with a single substrate accommodation hole 19 penetrating in the thickness direction. An annular substrate support portion 21 protrudes from the hole wall 15 d of the substrate accommodation hole 19. One substrate 2 accommodated in the substrate accommodation hole 19 is supported by the upper surface 21 a of the substrate support portion 21. As shown in FIGS. 25, 27A, and 27B, the dielectric plate 23 of the substrate susceptor 9 includes a single substrate mounting portion 29. When the tray 15 is placed on the dielectric plate 23, the substrate placement portion 29 enters the substrate accommodation hole 19 from the lower surface 15 c side of the tray 15, and the lower surface of the tray 15 is supported by the tray support surface 28 of the dielectric plate 23. At the same time, the substrate 2 is placed on the substrate placement surface 31 at the upper end of the substrate placement portion 29.

  The electrode for electrostatic attraction that electrostatically attracts the substrate 2 is a bipolar type. Specifically, the substrate mounting portion 29 includes two electrostatic adsorption electrodes 40A and 40B. Further, DC voltage application mechanisms 43E and 43F are provided for the individual electrostatic attraction electrodes 40A and 40B, and DC voltages having opposite polarities are applied to the individual electrostatic attraction electrodes 40A and 40B. In the first to eighth embodiments, the electrostatic chucking electrode may be a bipolar type. On the contrary, in this embodiment, the electrostatic chucking electrode may be a single electrode type.

  In the dry etching apparatus 1 of the present embodiment, since the substrate 2 accommodated in the tray 15 is one sheet, single wafer processing is possible. Moreover, it is suitable for processing the substrate 2 having a relatively large area.

  Since the other configurations and operations of the ninth 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.

(Experiment 1)
A simulation was performed to confirm that the cooling efficiency of the substrate is improved by the present invention. Specifically, the relationship between the increase in bias power and the increase in substrate temperature was simulated for Experimental Example, Comparative Example 1, and Comparative Example 2.

  The experimental example corresponds to the ninth embodiment of the present invention. The substrate 2 was a 2-inch silicon wafer. The tray 15 containing the substrate 2 is placed on the dielectric plate 23 of the substrate susceptor 9 in the substrate accommodation hole 19 penetrating the tray 15 in the thickness direction, and the lower surface 2 a of the substrate 2 is directly on the substrate placement surface 31. The electrode was placed and electrostatically attracted by bipolar electrostatic attracting electrodes 40A and 40B. The DC voltage applied to each of the electrostatic attraction electrodes 40A and 40B was ± 900V. Further, helium gas was supplied as a heat transfer gas between the substrate placement surface 31 and the lower surface 2a of the substrate 2, and the pressure was 800 Pa.

  Comparative Example 1 is an example in which a bottomed tray on which a substrate is placed is placed on a substrate susceptor, and the substrate is indirectly electrostatically attracted to the substrate susceptor via the tray. The substrate was a 2 inch size silicon wafer. The DC voltage applied to the electrostatic chucking electrode was ± 900 V, helium gas was supplied as the heat transfer gas to the lower surface of the tray, and the pressure was 800 Pa.

  In Comparative Example 2, a bottomed tray on which a substrate is placed is placed on a substrate susceptor, and the vicinity of the outer peripheral edge of the substrate is mechanically pressed to the substrate susceptor side by a clamp ring, whereby the substrate is pressed against the substrate susceptor. This is an example of fixing. The substrate was a 4 inch size silicon wafer. Moreover, helium was supplied to the lower surface of the substrate as a heat transfer gas, and the pressure was 600 Pa.

The following conditions were unified for the experimental example and comparative examples 1 and 2. The etching gas was chlorine gas (Cl ₂ ), the flow rate was 50 sccm, and the pressure was 2 Pa. The high frequency power supplied to the ICP coil was 300 W. The discharge time was 60 seconds. The temperatures of the top plate, chamber, and substrate susceptor (electrode) were 100 ° C., 100 ° C., and 20 ° C., respectively.

  FIG. 28 shows the simulation result. In Comparative Example 1, when the bias power is about 50 W, the substrate temperature rises to about 110 ° C. where resist burning occurs. In Comparative Example 2, when the bias power is about 200 W, the substrate temperature rises to about 110 ° C. where resist burning occurs. On the other hand, in the experimental example, even when the bias power is set to 400 W, the substrate temperature does not reach about 110 ° C. where resist burning occurs. This simulation result shows that the cooling efficiency of the substrate in the experimental example (the present invention) is significantly higher than in the conventional examples 1 and 2.

(Experiment 2)
A simulation for confirming that the plasma treatment in the entire region of the substrate surface is made uniform by the present invention was performed. In the above experimental example and comparative example 2, orthogonal coordinates (XY coordinate system) with the center of the substrate as the origin were set on the substrate surface, and the etching rate (E / R) distribution was simulated for these. In both the experimental example and the comparative example 2, the material of the substrate was nickel cobalt (NiCo).

  FIG. 29 shows the simulation result of Comparative Example 2, and FIG. 30 shows the simulation result of the experimental example. In Comparative Example 2, the etching rate is low near the outer periphery of the substrate as compared with the vicinity of the center of the substrate, and the distribution of the etching rate is non-uniform due to the presence of the clamp ring at the outer periphery of the substrate. Specifically, the average value of the etching rate at the position of 5 mm in the X direction and 5 mm in the Y direction from the center of the substrate is 42.5 nm / min, whereas it is 10 mm in the X direction from the center of the substrate and the Y direction. The average value of the etching rate at a position of 10 mm is 43.9 nm / min, and there is a difference of 1.4 nm / min between the two. On the other hand, in the experimental example, the etching rate is uniform in the entire region from the vicinity of the center of the substrate to the vicinity of the outer periphery. Specifically, the average value of the etching rate at a position of 5 mm in the X direction and 5 mm in the Y direction from the center of the substrate is 44.5 nm / min, 10 mm in the X direction and 10 mm in the Y direction from the center of the substrate. The average value of the etching rate is 43.9 nm / min, and the difference between them is only a difference of 0.6 nm / min. Compared to Comparative Example 2, in the experimental example (the present invention), the difference between the average values of the etching rates at the position of 5 mm and the position of 10 mm from the center of the substrate is reduced to less than ½.

  The present invention is not limited to the above embodiment, and various modifications can be made. For example, the present invention has been described by taking an ICP type dry etching processing apparatus as an example, but the present invention can be applied to an RI (reactive ion) type dry etching, a plasma processing apparatus for plasma CVD, and a plasma processing method.

1 is a schematic cross-sectional view of a dry etching apparatus according to a first embodiment of the present invention. 1 is a schematic plan view of a dry etching apparatus according to a first embodiment of the present invention. The perspective view which shows a tray and a dielectric material board. The top view of a tray. Sectional drawing in the IV-IV line of FIG. 4A. The partial expanded sectional view of a tray and a dielectric material board (before tray mounting). The partial expanded sectional view of a tray and a dielectric material board (after tray mounting). The top view of a dielectric material board. Sectional drawing in the VI-VI line of FIG. The partial expanded sectional view of the 1st alternative of a tray and a dielectric material board. The partial expanded sectional view of the 2nd alternative of a tray and a dielectric material board. The partial expanded sectional view of the 3rd alternative of a tray and a dielectric material board. The partial expanded sectional view of the 4th alternative of a tray and a dielectric material board. Sectional drawing which shows the tray and dielectric plate with which the dry etching apparatus which concerns on 2nd Embodiment of this invention is provided. The top view of a tray. Sectional drawing in the XII-XXII line | wire of FIG. 12A. The top view of a dielectric material board. Sectional drawing in the XIII-XIII line | wire of FIG. The top view which shows the 1st alternative of a tray. The top view which shows the 2nd alternative of a tray. The typical sectional view showing the dry etching device concerning a 3rd embodiment of the present invention. The elements on larger scale of the part XVII of FIG. The partial expanded sectional view which shows the 1st alternative of a tray and a guide plate. The partial expanded sectional view which shows the 2nd alternative of a tray and a guide plate. The typical sectional view showing the dry etching device concerning a 4th embodiment of the present invention. Typical sectional drawing which shows the dry etching apparatus which concerns on 5th Embodiment of this invention. Typical sectional drawing which shows the dry etching apparatus which concerns on 6th Embodiment of this invention. Typical sectional drawing which shows the dry etching apparatus which concerns on 7th Embodiment of this invention. Typical sectional drawing which shows the dry etching apparatus which concerns on 8th Embodiment of this invention. Typical sectional drawing which shows the dry etching apparatus which concerns on 9th Embodiment of this invention. The typical perspective view showing the tray and dielectric board with which the dry etching apparatus concerning a 9th embodiment of the present invention is provided. The top view of the tray with which the dry etching apparatus which concerns on 9th Embodiment of this invention is provided. FIG. 26B is a sectional view taken along line XXVI-XXVI in FIG. 26A. The top view of a dielectric material board. FIG. 27B is a sectional view taken along line XXVII-XXVII in FIG. 27A. The graph which shows the relationship between bias power and substrate temperature. 9 is a graph showing the etching rate distribution in Comparative Example 2. The graph which shows distribution of the etching rate in an experiment example.

DESCRIPTION OF SYMBOLS 1 Dry etching apparatus 2 Substrate 2a Lower surface 3 Chamber 3a Gate 3b Etching gas supply port 3c Exhaust port 4 Top plate 5 ICP coil 6 Matching circuit 7 High frequency power supply 9 Substrate susceptor 10 Load dock chamber 12 Etching gas supply source 13 Vacuum exhaust device 15 Tray 15a tray body 15b upper surface 15c lower surface 15d hole wall 15e positioning notch 15f outer peripheral surface 16 transfer arm 16a positioning protrusion 17 driving device 18 lift pins 19, 19A to 19D substrate accommodation hole 21 substrate support portion 21a upper surface 21b distal end surface 21c lower surface 22A, 22B Sensor 23 Dielectric plate 24 Metal plate 25 Spacer plate 26 Guide cylinder 27 Ground shield 28 Tray support surface 29, 29A to 29D Substrate placement portion 31 Substrate placement surface 32 Annular protrusion 33 Cylindrical protrusion 36 Circular opening 38 Outer peripheral surface 40, 40A, 40B Electrostatic adsorption electrode 41 DC power supply 42 Resistance 43, 43A-43F DC voltage application mechanism 44 Supply hole 45, 45A-45D Heat transfer gas supply mechanism 46 Heat transfer gas source 47 Supply flow Channel 48 Flow meter 49 Flow control valve 50 Pressure gauge 51 Discharge flow path 52 Cut-off valve 53 Bypass flow path 54 Exhaust port 56, 56A to 56D High frequency application mechanism 57 High frequency power supply 58 Variable capacity capacitor 59 Cooling mechanism 60 Refrigerant flow path 61 Refrigerant Circulating device 63 Controller 65 Housing groove 67 Guide plate 67a Inner peripheral surface 67b Lower surface 67c Upper surface 68 Bias application electrode

Claims (3)

A depressurizable chamber (3);
A plurality of substrate accommodation holes (19, 19A to 19I) each accommodating a substrate (2) are provided, and the chamber includes a substrate support portion (21) protruding from a hole wall (15d) of the substrate accommodation hole. A tray (15) capable of carrying in and out;
Wherein provided in the chamber, the tray support portion (28), a plurality of the lower surface of the substrate is mounted respectively to the projects upward from the tray support portion, and the substrate mounting surface which is the upper end surface thereof (31) A dielectric member (23) comprising a substrate mounting portion (29, 29A to 29D);
An electrostatic chucking electrode (40, 40A, 40B) for electrostatically attracting the substrate to the substrate mounting surface, at least part of which is built in the substrate mounting unit;
A DC voltage application mechanism (43, 43A to 43F) for applying a DC voltage to the electrode for electrostatic attraction;
A heat transfer gas supply mechanism (45, 45A to 45D) for supplying a heat transfer gas between the substrate and the substrate mounting surface;
The connecting portion between the substrate mounting surface and the outer peripheral surface of the substrate mounting portion is chamfered into a round surface, and the outer diameter increases from the substrate mounting surface side toward the tray support portion side,
The front end surface (21b) of the substrate support portion of the tray is a tapered surface in which the protruding amount from the hole wall increases from the lower surface (15c) side to the upper surface (15b) side of the tray,
When transporting the substrate, the outer peripheral edge portion of the lower surface of the substrate housed in the substrate housing hole is supported by the substrate support portion,
During processing of the substrate, the substrate mounting part is inserted from below surface side of the tray to the substrate receiving hole into which the substrate mounting surface is configured to enter the thickness direction of the tray, the substrate supporting unit the distal end surface is guided by the connecting portion of the outer peripheral surface of the substrate mounting portion and the substrate mounting surface of the lower surface of the tray is placed on the tray support portion of the dielectric member, the A plasma processing apparatus. The clearance between the outer peripheral surface of the substrate platform and the tip surface of the substrate support in a state where the tray is placed on the tray support is about 0.5 mm. The plasma processing apparatus as described. A plurality of substrate accommodation holes (19, 19A to 19I) each accommodating a substrate (2) are provided, and a substrate support part (21) protruding from a hole wall (15d) of the substrate accommodation hole is conveyed. A possible tray (15) , wherein the front end surface of the substrate support portion has a protruding amount from the hole wall increasing from the lower surface side to the upper surface side of the tray ;
It is arrange | positioned in the chamber (3) which can be pressure-reduced, It is provided with a tray support part (28) and several board | substrate mounting parts (29A-29D) which protrude upwards from this tray support part, connecting portions between the outer peripheral surface of the substrate mounting surface which is the upper end face the substrate placing portion outside diameter are chamfered into a round surface increases toward the tray support portion from the substrate support surface, and electrostatic Preparing a dielectric member (23) in which at least a part of the substrate mounting portion is built in the adsorption electrodes (40A, 40B);
The substrate (2) to the substrate accommodation hole of the tray housed respectively in a state where the outer peripheral edge portion supported on the lower surface of the substrate by the substrate support portion (2a), carried the tray into the chamber,
Placing the tray above the dielectric member;
The tray is lowered toward the dielectric member, and the substrate placement portions (29A to 29D) are respectively entered into the substrate accommodation holes from the lower surface side of the tray, and the substrate placement surface and the outer peripheral surface Guiding the front end surface of the substrate support portion at the connection portion;
The lower surface of the substrate is placed on the tray support portion (28) of the dielectric member, and the lower surface (2a) of the substrate is lifted by the substrate placement surface of the substrate placement portion that has entered the substrate accommodation hole, The substrate is placed on the substrate placement surface so as to be disposed above the upper surface (21a) of the substrate support portion of the tray with a gap therebetween,
A DC voltage is applied to the electrostatic chucking electrode (40) at least partially incorporated in the substrate mounting part to electrostatically attract the substrate to the substrate mounting surface;
Supplying a heat transfer gas to a space surrounded by the lower surface of each of the substrates and the annular protrusion of each of the substrate mounting portions;
A plasma processing method for generating plasma in the chamber.

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