JP2008244079A - Film-forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide film-forming apparatus capable of forming a film stably without generating abnormal discharge in the film-forming equipment. <P>SOLUTION: In the film-forming apparatus, a coil 60 for blocking a gap having an annular center axis is interposed between a heater 15 and a heater base 3 along the periphery of the heater 15. The heater 15 and the heater base 3 are composed so that they can be elevated. A flexible, conductive plate member 30 for holding the chamber 2, heater 15 and heater base 3 at the same potential is arranged so that it joins the chamber 2, heater base 3 and heater 15. The plate member 30 is energized to the heater base 3 and heater 15 by a coil 60 for energizing plates having an annular center axis arranged in parallel with the plate member 30. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a film forming apparatus.

  2. Description of the Related Art Conventionally, a plasma CVD apparatus that decomposes a source gas using plasma and forms a thin film on a substrate is known (see, for example, Patent Document 1). With this plasma CVD apparatus, for example, an amorphous silicon (a-Si) film can be formed on a substrate.

  7 and 8 show a film forming apparatus 101 that performs a conventionally known plasma CVD method. The film forming apparatus 101 has a vacuum chamber 102. A support column 125 is disposed below the vacuum chamber 102 so as to pass through the bottom surface of the vacuum chamber 102. A plate-like heater base 103 is attached to the tip of the column 125 in the vacuum chamber 102. An electrode flange 104 is attached to the upper portion of the vacuum chamber 102 via an insulating flange 181.

  The electrode flange 104 is formed in a bottomed container shape, and a shower plate 105 is attached to the container opening so as to cover the inside of the container. Therefore, a space 124 is formed between the shower plate 105 and the electrode flange 104.

  A gas introduction pipe 107 is connected to the electrode flange 104 so that a film forming gas can be introduced into the space 124 from the film forming gas supply unit 121. The shower plate 105 is provided with a large number of gas jets 106, and the film forming gas introduced into the space 124 is jetted into the vacuum chamber 102 from the gas jets 106.

  Further, when the substrate 110 is formed, the film forming material adheres to the inner wall surface of the vacuum chamber 102 and the like, so that the fluorine gas supplied from the fluorine gas supply unit 122 connected to the vacuum chamber 102 is converted into radical It is configured so that it can be decomposed by the source 123, and fluorine radicals thereby can be supplied to the film formation space in the vacuum chamber 102 to remove the deposit (film formation material).

  The heater base 103 has a flat surface, and the heater 115 is placed on the upper surface thereof. By placing the heater 115 on the heater base 103 in this way, the deformation amount of the heater 115 can be suppressed. The heater 115 has a flat surface similar to the heater base 103, and the substrate 110 is placed on the upper surface thereof. When the board | substrate 110 is arrange | positioned, the board | substrate 110 and the shower plate 105 are comprised so that it may mutually adjoin and may be located in substantially parallel. When the deposition gas is ejected from the gas ejection port 106 with the substrate 110 placed on the heater 115, the deposition gas is sprayed onto the surface of the substrate 110.

  The electrode flange 104 and the shower plate 105 are both made of a conductive material, and the electrode flange 104 is connected to an RF power source (high frequency power source) 109 provided outside the vacuum chamber 102.

  A plurality of ground plates 130 made of a conductive material are arranged so as to connect the back surface 112 of the heater base 103 and the wall surface 133 of the vacuum chamber 102. One end of the ground plate 130 is fixed to the back surface 112 of the heater base 103 with a bolt 141, and the other end is fixed to the inner wall surface 133 of the vacuum chamber 102 with a bolt 141. That is, when the vacuum chamber 102 is maintained at the ground potential, the heater 115 and the heater base 103 are also maintained at the ground potential via the ground plate 130.

  In order to form a thin film on the surface of the substrate 110 using the film forming apparatus 101 having the above configuration, first, the vacuum chamber 102 is evacuated by the vacuum pump 128. With the vacuum chamber 102 maintained in a vacuum state, the substrate 110 is carried into the vacuum chamber 102 and placed on the heater 115. Thereafter, a deposition gas (raw material gas) is introduced from the gas introduction pipe 107, and the deposition gas is ejected from the gas ejection port 106 into the vacuum chamber 102.

  The electrode flange 104 is insulated from the vacuum chamber 102 via the insulating flange 181, and the RF power source 109 is activated to apply a high frequency voltage to the electrode flange 104 with the vacuum chamber 102 connected to the ground potential. Then, a high frequency voltage is applied between the shower plate 105 and the heater 115 to generate a discharge, and plasma is generated between the electrode flange 104 and the surface of the substrate 110. The deposition gas is decomposed in the plasma generated in this way, and a vapor phase growth reaction occurs on the surface of the substrate 110, whereby a thin film is formed on the surface of the substrate 110.

  Further, when the film formation on the substrate 110 is repeated several times, the film forming material adheres to the inner wall surface 133 of the vacuum chamber 102 and the like, and thus the inside of the vacuum chamber 102 is cleaned. In the cleaning, the fluorine gas supplied from the fluorine gas supply unit 122 connected to the vacuum chamber 102 is decomposed by the radical source 123, and the resulting fluorine radicals are supplied to the film forming space in the vacuum chamber 102 to cause a chemical reaction. To remove deposits.

  Here, in the plasma CVD method, it is common to use a high-frequency power source whose oscillation frequency is usually 13.56 MHz. In order to obtain a film forming speed that can be used for mass production with a plasma CVD apparatus, the pressure in the film forming space is often set to 100 Pa to 300 Pa. Under this pressure condition, the interelectrode distance between the shower plate 105 to which a voltage is applied and the heater 115 functioning as a ground electrode is generally about 15 to 25 mm.

It is difficult to take in and out the substrate 110 in such a narrow space. In particular, in the current situation where the size of the substrate 110 is increasing, the difficulty of taking in and out the substrate 110 is further increased. In order to solve this problem, the heater base 103 and the heater 115 are known so as to be movable up and down. In the film forming apparatus 101 configured such that the heater base 103 and the heater 115 can be moved up and down, the potential of the heater base 103 and the heater 115 and the potential of the vacuum chamber 102 are set to the same potential, that is, to the ground potential. For this purpose, a ground plate 130 having flexibility is provided.
JP-A-10-310866

  By the way, in the above-described film forming apparatus 101, the heater 115 is heated to 200 to 480 ° C. and the heater base 103 is heated to 180 to 450 ° C. during film formation. (By the way, since the vacuum chamber 102 is cooled with water, the temperature becomes 80 to 100 ° C.) Since the heater 115 is made of, for example, an aluminum alloy, the heater 115 is deformed by heat at such a high temperature. A gap d ′ is formed between 115 and the heater base 103. When such a gap d ′ is formed, there is a problem that the impedance between the heater 115 and the heater base 103 changes and abnormal discharge occurs.

  Further, a gap is also generated at the connection portion between the heater base 103 and the earth plate 130, and fluorine radicals enter the gap during cleaning, whereby corrosion progresses or abnormal discharge occurs. was there. As a result, the stability of the plasma is lowered, and there is a risk that the film formation varies.

  Therefore, the present invention has been made in view of the above circumstances, and provides a film forming apparatus capable of performing stable film formation without causing abnormal discharge in the film forming apparatus.

  According to the first aspect of the present invention, there is provided a chamber configured to be capable of applying an AC voltage by introducing a film forming material gas, a heater disposed in the chamber and configured to be capable of mounting a substrate, and the heater In the film forming apparatus including the heater base configured to be capable of mounting a gap, a gap closing coil having an annular central axis along the peripheral edge of the heater is interposed between the heater and the heater base. It is characterized by being dressed.

  With this configuration, even when the heater becomes hot and deforms and a gap is generated between the heater and the heater base, the heater and the heater are elastically deformed by the gap closing coil provided on the peripheral edge of the heater. Since the gap formed between the base and the base can be connected semi-continuously and closed as a high-frequency circuit due to the skin effect, it is possible to prevent electromagnetic waves from entering between the heater and the heater base. Therefore, it is possible to prevent the occurrence of abnormal discharge in the gap and to achieve stable film formation.

  The invention described in claim 2 includes a chamber configured to be capable of applying an AC voltage by introducing a film forming material gas, and a table disposed in the chamber and configured to be capable of mounting a substrate. In the film forming apparatus, the table is configured to be movable up and down, and in order to hold the chamber and the table at the same potential, a plate member having flexibility and conductivity is joined to the chamber and the table, and the plate The member is biased to the table by a plate biasing coil having an annular central axis arranged in parallel with the plate member.

  With this configuration, even when a gap is generated between the table and the plate member due to aged reasons, the gap between the table and the plate member is blocked by the biasing force of the plate biasing coil. Therefore, it is possible to prevent occurrence of abnormal discharge due to an increase in contact resistance. As a result, there is an effect that stable film formation can be performed.

  The invention described in claim 3 includes a chamber configured to be capable of applying an AC voltage by introducing a film forming material gas, and a table disposed in the chamber and configured to be capable of mounting a substrate. In the film forming apparatus, the table is configured to be movable up and down, and in order to hold the chamber and the table at the same potential, a plate member having flexibility and conductivity is joined to the chamber and the table, and the plate The member is urged against the table by a plate urging coil having an annular central axis arranged in parallel with the plate member, and the table includes a heater configured to mount the substrate, A heater base configured to be capable of placing a heater, and a gap having an annular central axis along a peripheral edge of the heater between the heater and the heater base. Is characterized by occlusive coil is interposed.

With this configuration, even when a gap is generated between the table and the plate member due to aged reasons, the gap between the table and the plate member is blocked by the biasing force of the plate biasing coil. Therefore, it is possible to prevent occurrence of abnormal discharge due to an increase in contact resistance.
Even when the heater becomes hot and deforms to form a gap between the heater and the heater base, the gap is formed between the heater and the heater base by elastic deformation of the gap closing coil provided on the peripheral edge of the heater. Since the gaps to be formed can be connected semi-continuously and closed as a high-frequency circuit due to the skin effect, intrusion of electromagnetic waves between the heater and the heater base can be prevented. Therefore, occurrence of abnormal discharge in the gap can be prevented.
As a result, a plate energizing coil is arranged at the connection portion between the table and the plate member, and a gap closing coil is arranged between the heater and the heater base, so that more reliable and stable film formation can be performed. There is an effect that can.

  The invention described in claim 4 is characterized in that the chamber is configured to be capable of introducing a cleaning gas for removing deposits inside the chamber.

  With this configuration, even if a cleaning gas composed of fluorine radicals or the like is introduced into the chamber, the cleaning gas enters between the table and the plate member that is energized by the plate energizing coil. Can be prevented. Therefore, it is possible to prevent the occurrence of corrosion at the contact between the table and the plate member, thereby preventing the occurrence of abnormal discharge due to the increase in contact resistance. As a result, there is an effect that stable film formation can be performed.

  According to a fifth aspect of the present invention, the central axis of the plate biasing coil is disposed so as to surround a shaft portion of a bolt that joins the plate member to the table, and the plate biasing coil is It is characterized by being interposed between the head of the bolt and the plate member.

  With this configuration, the plate member and the table can be firmly tightened with the bolt, and even when the bolt is loosened over time, the plate urging coil can be used to connect the plate member and the table between the plate member and the table. Therefore, it is possible to prevent the entry of gas such as fluorine radicals between the table and the plate member at the portion energized by the plate energizing coil. Therefore, it is possible to prevent the occurrence of corrosion at the contact between the table and the plate member, thereby preventing the occurrence of abnormal discharge due to the increase in contact resistance. As a result, there is an effect that stable film formation can be performed.

  According to a sixth aspect of the present invention, the table includes a heater configured to mount the substrate, and a heater base configured to mount the heater, and the plate member includes the plate. The heater base is biased by a bias coil and is joined to the heater base.

  With this configuration, even when the bolt that joins the heater base and the plate member is loosened due to aging, etc., the bias between the heater base and the plate member is caused by the biasing force of the plate biasing coil. Since the gap between them can be closed, it is possible to prevent the entry of gas such as fluorine radicals between the heater base and the plate member in the portion energized by the plate energizing coil. Therefore, it is possible to prevent the corrosion of the contact between the heater base and the plate member, and it is possible to prevent the occurrence of abnormal discharge due to the increase in contact resistance. As a result, there is an effect that stable film formation can be performed.

  According to a seventh aspect of the present invention, the table includes a heater configured to be capable of mounting the substrate, and a heater base configured to be capable of mounting the heater. The plate biasing coil is biased to the heater base and joined to the heater base, and the second plate biasing coil is biased to the heater and joined to the heater. It is characterized by that.

With this configuration, even when the bolt that joins the heater base and the plate member is loosened due to aging or the like, the heater base and the plate are biased by the biasing force of the first plate biasing coil. Since the gap between the member and the member can be closed, intrusion of gases such as fluorine radicals between the heater base and the plate member in the portion energized by the first plate energizing coil is prevented. be able to. Therefore, it is possible to prevent the corrosion of the contact between the heater base and the plate member, and it is possible to prevent the occurrence of abnormal discharge due to the increase in contact resistance.
Similarly, even when the bolt that joins the heater and the plate member is loosened due to aging, the gap between the heater and the plate member is reduced by the urging force of the second plate urging coil. Since it can be blocked, the same effect can be obtained.
Further, since the plate member is fixed not only to the heater base but also to the heater with bolts, the plate member can be fixed more firmly. Accordingly, it is possible to make it difficult to form a gap between the heater and the heater base at a high temperature, and it is possible to perform more stable film formation without causing abnormal discharge.

  The invention described in claim 8 is characterized in that the bolt is made of a nickel alloy.

  With this configuration, the bolt has strength, heat resistance and corrosion resistance, so it will not be deformed even at high temperatures and will not corrode even when fluorine radicals or other gases are present in the vacuum chamber. Function. Therefore, there is an effect that the occurrence of abnormal discharge can be prevented.

  The invention described in claim 9 is characterized in that the plate biasing coil is made of a nickel alloy.

  By configuring in this way, the plate biasing coil has heat resistance and corrosion resistance, so it does not deform even at high temperatures, and even if a gas such as fluorine radicals is present in the vacuum chamber, it is difficult to corrode. Works reliably. Therefore, there is an effect that the occurrence of abnormal discharge can be prevented.

The invention described in claim 10 is characterized in that the gap closing coil is made of a nickel alloy.
With this configuration, the gap closing coil has heat resistance and corrosion resistance, so that it does not deform even at high temperatures, and even if a gas such as fluorine radicals is present in the vacuum chamber, it is difficult to corrode and reliably. To work. Therefore, there is an effect that the occurrence of abnormal discharge can be prevented.

  According to the present invention, even when a heater is heated and deformed at the time of film formation or the like and a gap is generated between the heater and the heater base, due to the elastic deformation of the gap closing coil provided on the peripheral edge of the heater. Since the gap formed between the heater and the heater base can be semi-continuously connected and closed as a high-frequency circuit due to the skin effect, electromagnetic waves can be prevented from entering between the heater and the heater base. it can. Therefore, occurrence of abnormal discharge in the gap can be prevented. As a result, by providing the gap closing coil between the heater and the heater base, there is an effect that stable film formation can be performed.

Further, even when a gap occurs between the heater base and the plate member due to aging, the heater base and the plate are urged by the urging force of the first plate urging coil provided between the bolt and the plate member. The gap between the members can be closed.
Further, even when a gap is generated between the heater and the plate member due to aging, the heater and the plate member are separated by the urging force of the second plate urging coil provided between the bolt and the plate member. The gap between the two can be closed.

  Therefore, it is possible to prevent entry of fluorine radicals or the like as a cleaning gas between the heater base and the plate member of the portion urged by the plate urging coil and between the heater and the plate member. Corrosion of the contact between the heater and the heater base and the plate member can be prevented. Therefore, it is possible to prevent the occurrence of abnormal discharge due to the increase in contact resistance. As a result, the first and second plate urging coils are provided in the connection portion between the heater base and the plate member and the connection portion between the heater and the plate member, thereby providing an effect of performing stable film formation. is there.

  Next, an embodiment of the present invention will be described with reference to FIGS. In each drawing used for the following description, the scale of each member is appropriately changed to make each member a recognizable size.

FIG. 1 is a schematic configuration diagram of a film forming apparatus in the present embodiment.
As shown in FIG. 1, a film forming apparatus 1 that performs a plasma CVD method has a vacuum chamber 2. A support column 25 is disposed below the vacuum chamber 2 so as to pass through the bottom 11 of the vacuum chamber 2, and the tip of the support column 25 (in the vacuum chamber 2) is connected to the bottom surface 12 of the plate-shaped heater base 3. Has been. The electrode flange 4 is attached to the upper part of the vacuum chamber 2 via an insulating flange 81. In addition, an exhaust pipe 27 is connected to the vacuum chamber 2, and a vacuum pump 28 is provided at the tip of the vacuum chamber 2, so that the inside of the vacuum chamber 2 can be evacuated.

  The support column 25 is connected to an elevating mechanism (not shown) provided outside the vacuum chamber 2 and is configured to be movable in the vertical direction. That is, the heater base 3 and the heater 15 connected to the tip of the column 25 can be moved up and down. A bellows 26 is provided outside the vacuum chamber 2 so as to cover the periphery of the column 25.

  The electrode flange 4 is formed in a bottomed container shape, and a shower plate 5 is attached to the container opening so as to cover the inside of the container. Therefore, a space 24 is formed between the shower plate 5 and the electrode flange 4.

A gas introduction pipe 7 is connected to the electrode flange 4 and is configured to supply a source gas (for example, SiH ₄ ) to the space 24 from a film forming gas supply unit 21 provided outside the vacuum chamber 2. Yes. The shower plate 5 is provided with a large number of gas jets 6, and the film forming gas introduced into the space 24 is jetted from the gas jets 6 into the vacuum chamber 2.

  The electrode flange 4 and the shower plate 5 are both made of a conductive material, and the electrode flange 4 is connected to an RF power source (high frequency power source) 9 provided outside the vacuum chamber 2.

  Further, another gas introduction pipe 8 is connected to the vacuum chamber 2. The gas introduction pipe 8 is provided with a fluorine gas supply unit 22 and a radical source 23. The fluorine gas supplied from the fluorine gas supply unit 22 is decomposed by the radical source 23, and the resulting fluorine radicals are converted into the vacuum chamber 2. It is configured to be supplied to the film forming space inside.

  The heater base 3 is a plate-like member having a flat surface, and the heater 15 is placed on the upper surface thereof. The heater base 3 is formed of a nickel-based alloy such as Inconel (registered trademark). The heater base 3 only needs to have rigidity, corrosion resistance, and heat resistance.

  The heater 15 is a plate-like member having a flat surface similar to the heater base 3, and the substrate 10 is placed on the upper surface thereof. The heater 15 is made of, for example, an aluminum alloy. Since the heater 15 functions as a ground electrode, a conductive material is employed. When the substrate 10 is disposed on the heater 15, the substrate 10 and the shower plate 5 are configured to be positioned close to each other and in parallel. When the deposition gas is ejected from the gas ejection port 6 with the substrate 10 placed on the heater 15, the deposition gas is sprayed onto the surface of the substrate 10.

  The heater 15 includes a heater wire 16 therein, and is configured to be temperature adjustable. The heater wire 16 protrudes from the bottom surface 17 of the substantially central portion in the plan view of the heater 15, and passes through the inside of the through hole 18 and the column 25 formed in the substantially central portion of the heater base 3 in the plan view. 2 to the outside. The heater wire 16 is connected to a power source (not shown) outside the vacuum chamber 2 so that the temperature is adjusted.

FIG. 2 is an enlarged detail view of part A in FIG.
As shown in FIG. 2, a recess 55 is formed along the outer peripheral shape of the heater 15 at a position corresponding to the inside of the peripheral edge of the heater 15 on the surface 31 of the heater base 3. An annular gap closing coil 60 is disposed in the recess 55.

4A and 4B show the gap closing coil 60, where FIG. 4A is a plan view and FIG. 4B is a partial side view.
As shown in FIG. 4, the gap closing coil 60 is formed such that one steel wire is formed in a spiral shape and the central shaft 61 is annular. When a load is applied to the gap closing coil 60 having an annular shape in plan view from above, the steel wires stacked in a spiral shape are inclined and contract in the height direction. At this time, an upward urging force for returning to the original shape works. The gap closing coil 60 has a size that slightly protrudes from the surface 31 in a state where it is disposed in the recess 55. The heater 15 is placed above the gap closing coil 60 in the recess 55.

FIG. 3 is a perspective view showing a ground plate attached state.
As shown in FIGS. 2 and 3, a plurality of ground plates 30 are arranged at substantially equal intervals so as to connect between the heater base 3 and the heater 15 and the vacuum chamber 2. One end of the ground plate 30 is fixed to the surface 31 of the heater base 3 and the side surface 32 of the heater 15 with bolts 40, and the other end is fixed to the inner wall surface 33 of the vacuum chamber 2 with bolts 41.

  Here, the ground plate 30 is connected to the inner wall surface 33 of the vacuum chamber 2 by bolts 41, extends downward from the connecting portion along the inner wall surface 33, and is slightly forward of the bottom 11 of the vacuum chamber 2. Is folded in a substantially U shape and extended upward. The ground plate 30 extended upward is extended further upward on the side surface 34 while being in contact with the side surface 34 of the heater base 3, and is folded back at a substantially right angle so as to contact the surface 31 of the heater base 3. 31 is extended along the side surface 32 of the heater 15 by being folded upward at a substantially right angle at a connecting portion 35 between the heater base 3 and the heater 15.

  The ground plate 30 is formed of a flexible metal plate, and is made of, for example, a nickel alloy or an aluminum alloy. The earth plate 30 has a width of about 50 mm and a thickness of about 0.1 mm. The earth plate 30 may be made of a conductive material having a width of about 10 to 200 mm, high corrosion resistance, and flexibility.

  The bolt 40 is formed of a nickel-based alloy such as Inconel (registered trademark) or Hastelloy (registered trademark). A concave portion 47 is formed on the bottom surface 45 of the head portion 44 of the bolt 40 along the periphery of the shaft portion 46. Here, an annular plate biasing coil 50 formed of a nickel-based alloy such as Inconel (registered trademark) or Hastelloy (registered trademark) is disposed in the recess 47 through the shaft portion 46. The plate urging coil 50 has substantially the same configuration as the gap closing coil 60 and has a different size. The plate biasing coil 50 has a size such that it slightly protrudes from the bottom surface 45 in a state where it is disposed in the recess 47. The bolt 40 is fixed by screwing a shaft portion 46 into a screw hole 51 formed in the heater base 3 and the heater 15. Furthermore, a through hole 52 through which the shaft portion 46 of the bolt 40 can be inserted is formed at a position corresponding to the screw hole 51 in the ground plate 30.

  Further, the inner wall surface 33 of the vacuum chamber 2 and the earth plate 30 are fixedly connected by bolts 41. The material of the bolt 41 is not particularly limited because the vicinity of the inner wall surface 33 of the vacuum chamber 2 does not become high temperature.

(Function)
Next, an operation when a film is formed on the substrate 10 using the film forming apparatus 1 will be described.
In order to form a thin film on the surface of the substrate 10 using the film forming apparatus 1 having the above configuration, first, the vacuum chamber 2 is evacuated by the vacuum pump 28. With the vacuum chamber 2 maintained in a vacuum state, the substrate 10 is carried into the vacuum chamber 2 and placed on the heater 15. Here, before the substrate 10 is placed, the heater 15 is positioned below the vacuum chamber 2. That is, the space between the heater 15 and the shower plate 5 is wide, and the substrate 10 is held in a state where it can be easily placed on the heater 15. Then, after the substrate 10 is placed on the heater 15, a lifting device (not shown) is activated and the support column 25 is pushed upward, and the substrate 10 placed on the heater 15 moves upward accordingly. Thus, the distance from the shower plate 5 is kept at an appropriate distance for film formation. Thereafter, a film forming gas (raw material gas) is introduced from the gas introduction pipe 7, and the film forming gas is ejected into the vacuum chamber 2 from the gas ejection port 6.

  The electrode flange 4 is insulated from the vacuum chamber 2 via an insulating flange 81, and the RF power source 9 is activated to apply a high frequency voltage to the electrode flange 4 in a state where the vacuum chamber 2 is connected to the ground potential. Then, a high frequency voltage is applied between the shower plate 5 and the heater 15 to generate a discharge, and plasma is generated between the electrode flange 4 and the surface of the substrate 10. The deposition gas is decomposed in the plasma generated in this way, and a vapor phase growth reaction occurs on the surface of the substrate 10, whereby a thin film is formed on the surface of the substrate 10.

  Note that a high frequency power supply of 13.56 MHz is used as the oscillation frequency. Further, in order to obtain a film forming speed that can be used for mass production with such a film forming apparatus 1, the pressure in the film forming space is set to 100 Pa to 300 Pa. Under this pressure condition, the interelectrode distance between the shower plate 5 to which a voltage is applied and the heater 15 as a ground electrode is generally about 15 to 25 mm.

  When the film formation on the substrate 10 is repeated several times, the film forming material adheres to the inner wall surface 33 of the vacuum chamber 2 and the like, so that the inside of the vacuum chamber 2 is periodically cleaned. In the cleaning, the fluorine gas supplied from the fluorine gas supply unit 22 provided in the gas introduction pipe 8 connected to the vacuum chamber 2 is decomposed by the radical source 23, and the fluorine radicals formed thereby are formed into a film in the vacuum chamber 2. The deposits are removed by supplying to the space and causing a chemical reaction.

  By the way, in the above-mentioned film-forming apparatus 1, the heater 15 will be in a high temperature state by heating the heater wire 16 at the time of film-forming. At this time, the heater 15 has a temperature of 450 to 460 ° C., and the heater base 3 is substantially the same as the heater 15 and has a slightly lower temperature. (By the way, since the vacuum chamber 2 is water-cooled, the temperature is 80 to 100 ° C.) Since the heater 15 is made of an aluminum alloy, the heater 15 is bent up and down by heat at such a high temperature. . That is, it deform | transforms so that the center part of the heater 15 may rise, or it deform | transforms so that the peripheral part of the heater 15 may float. Since the heater base 3 is formed of Inconel (registered trademark), the amount of deformation is small as compared with the aluminum alloy. Accordingly, a gap d is formed between the heater 15 and the heater base 3 (see FIG. 2).

  Here, a gap closing coil 60 is interposed between the heater 15 and the heater base 3. The gap closing coil 60 is arranged so as to close the gap d formed at the peripheral edge of the heater 15 by elastic deformation of the gap closing coil 60. Accordingly, the gap d between the heater 15 and the heater base 3 can be semi-continuously connected and closed as a high-frequency circuit due to the skin effect, so that intrusion of electromagnetic waves into the gap d can be prevented.

  In addition, the plate biasing coil 50 is disposed on the bottom surface 45 of the head 44 of the bolt 40 that joins the heater base 3 and the earth plate 30, and then the heater base 3 and the earth plate 30 are joined by the bolt 40. ing. Therefore, even if the bolt 40 is loosened with time, the gap formed between the heater base 3 and the earth plate 30 can be closed by the biasing force of the plate biasing coil 50, so Intrusion of gas such as fluorine radicals supplied when cleaning the inside of the vacuum chamber 2 can be prevented between the heater base 3 and the earth plate 30 in the energized portion.

  Similarly, after the plate biasing coil 50 is disposed on the bottom surface 45 of the head 44 of the bolt 40 that connects the heater 15 and the earth plate 30, the heater 15 and the earth plate 30 are joined by the bolt 40. Yes. Therefore, even if the bolt 40 is loosened with time, the gap formed between the heater 15 and the ground plate 30 can be closed by the urging force of the plate urging coil 50, so that the urging force is applied by the plate urging coil 50. Intrusion of gas such as fluorine radicals supplied when the inside of the vacuum chamber 2 is cleaned can be prevented between the heater 15 and the earth plate 30 at the portion.

  Further, since the earth plate 30 is provided so as to connect the heater 15 and the heater base 3, it is possible to prevent the gap d from being formed between the heater 15 and the heater base 3 at a high temperature. it can.

  According to the present embodiment, the vacuum chamber 2 configured to be capable of applying an AC voltage by introducing a film forming material gas, and the heater 15 disposed in the vacuum chamber 2 and configured to mount the substrate 10 thereon. In the film forming apparatus 1 including the heater base 3 configured to be able to place the heater 15, an annular central axis 61 along the peripheral edge of the heater 15 is provided between the heater 15 and the heater base 3. A gap closing coil 60 was interposed.

  With this configuration, even when the heater 15 becomes hot and deforms and a gap is generated between the heater 15 and the heater base 3, due to the elastic deformation of the gap closing coil 60 provided at the periphery of the heater 15. A gap d formed between the heater 15 and the heater base 3 can be connected semi-continuously, and can be closed as a high-frequency circuit due to the skin effect. Therefore, electromagnetic waves can be prevented from entering between the heater 15 and the heater base 3, so that abnormal discharge in the gap d can be prevented and stable film formation can be performed.

  Further, the heater 15 and the heater base 3 are configured to be movable up and down, and in order to maintain the vacuum chamber 2 and the heater 15 and the heater base 3 at the same potential, the ground plate 30 having flexibility and conductivity is attached to the vacuum chamber 2. In addition to being joined to the heater base 3, the heater base 3 is arranged to be urged by a first plate urging coil 50 having an annular center shaft 61 arranged in parallel to the earth plate 30.

  With this configuration, even when a gap is generated between the heater base 3 and the ground plate 30 due to aging or the like, the heater base 3 and the ground plate 30 are biased by the biasing force of the first plate biasing coil 50. The gap between the two can be closed. Therefore, the occurrence of abnormal discharge due to the increase in contact resistance can be prevented, and stable film formation can be performed.

  Further, the earth plate 30 is joined to the heater 15 and is urged by the heater 15 by the second plate urging coil 50 having an annular center shaft 61 arranged in parallel with the earth plate 30. Arranged.

  With this configuration, even when a gap is generated between the heater 15 and the ground plate 30 due to aging or the like, the bias between the heater 15 and the ground plate 30 is caused by the biasing force of the second plate biasing coil 50. The gap between them can be closed. Therefore, the occurrence of abnormal discharge due to the increase in contact resistance can be prevented, and stable film formation can be performed.

  Furthermore, the earth plate 30 is joined not only to the heater base 3 but also to the heater 15, and the earth plate 30 can be fixed more firmly. Therefore, even if the gap d is formed between the heater 15 and the heater base 3 at a high temperature, the impedance does not fluctuate and a more stable film formation can be performed without causing abnormal discharge.

  Further, the vacuum chamber 2 is provided with a fluorine gas supply unit 22 and a radical source 23 in order to remove deposits inside the vacuum chamber 2 so that a cleaning gas can be introduced.

  With this configuration, even when a cleaning gas composed of fluorine radicals or the like is introduced into the vacuum chamber 2, the heater base 3 and the earth plate 30 that are energized by the plate energizing coil 50 and the heater It is possible to prevent the cleaning gas from entering between 15 and the ground plate 30. Therefore, it is possible to prevent the corrosion of the contacts of the heater 15 and the heater base 3 and the earth plate 30 and to prevent the occurrence of abnormal discharge due to the increase in contact resistance. As a result, there is an effect that stable film formation can be performed.

  Further, the plate urging coil 50 is arranged so that the central shaft 61 surrounds the shaft portion 46 of the bolt 40 that joins the ground plate 30 and the heater base 3 or the heater 15, and the head 44 of the bolt 40 and the ground. It was interposed between the plates 30.

  With this configuration, the ground plate 30 and the heater base 3 can be firmly tightened by the bolt 40, and the first plate biasing coil 50 can be secured even when the bolt 40 is loosened over time. The gap between the earth plate 30 and the heater base 3 can be closed by the urging force. Therefore, it is possible to prevent entry of fluorine radicals or the like between the heater base 3 and the earth plate 30 in the portion energized by the first plate energizing coil 50 during cleaning of the vacuum chamber 2 or the like. Therefore, the corrosion of the contact between the heater base 3 and the earth plate 30 can be prevented. Therefore, it is possible to prevent the occurrence of abnormal discharge due to the increase in contact resistance, thereby providing an effect of performing stable film formation.

  Similarly, the ground plate 30 and the heater 15 can be firmly tightened by the bolt 40, and when the bolt 40 is loosened with time, the ground plate 30 and the heater 15 are grounded by the biasing force of the second plate biasing coil 50. A gap between the plate 30 and the heater 15 can be closed. Accordingly, it is possible to prevent entry of fluorine radicals or the like between the heater 15 and the earth plate 30 in the portion energized by the second plate energizing coil 50 during cleaning of the vacuum chamber 2 or the like. Therefore, the corrosion of the contact between the heater 15 and the ground plate 30 can be prevented. Therefore, it is possible to prevent the occurrence of abnormal discharge due to the increase in contact resistance, thereby providing an effect of performing stable film formation.

  Furthermore, since the bolt 40 is made of a nickel alloy, the bolt 40 can be provided with strength, heat resistance and corrosion resistance. Therefore, the bolt 40 is not deformed even at a high temperature, is not easily corroded by fluorine radicals, and can reliably function as a bolt. Therefore, occurrence of abnormal discharge can be prevented.

  Since the plate urging coil 50 is made of a nickel alloy, the plate urging coil 50 can be provided with heat resistance and corrosion resistance. Therefore, the plate urging coil 50 is not deformed even at a high temperature, is hardly corroded by fluorine radicals, and can reliably function as a spring coil. Therefore, it is possible to prevent occurrence of abnormal discharge between the ground plate 30 and the heater base 3 and between the ground plate 30 and the heater 15, respectively.

  Similarly, since the gap closing coil 60 is made of a nickel alloy, the gap closing coil 60 can be provided with heat resistance and corrosion resistance. Therefore, the gap closing coil 60 is not deformed even at a high temperature, is hardly corroded by fluorine radicals, and can reliably function as a spring coil. Therefore, it is possible to prevent abnormal discharge from occurring between the heater 15 and the heater base 3.

  It should be noted that the technical scope of the present invention is not limited to the above-described embodiment, and includes those in which various modifications are made to the above-described embodiment without departing from the spirit of the present invention. That is, the specific materials, configurations, and the like given in the embodiment are merely examples, and can be changed as appropriate.

  For example, in the present embodiment, the case where the bolts 40 are provided both between the ground plate 30 and the heater base 3 and between the ground plate 30 and the heater 15 has been described. As shown in FIGS. Further, the bolt 40 may be provided only between one of the ground plate 30 and the heater base 3 and between the ground plate 30 and the heater 15.

  As shown in FIG. 5, when the earth plate 30 is joined with the heater base 3 and the bolt 40, the size of the earth plate 30 can be reduced as much as possible, and the same as the above-described embodiment while saving resources. The occurrence of corrosion can be prevented and the occurrence of abnormal discharge due to an increase in contact resistance can be prevented. As a result, stable film formation can be performed. The position where the bolt 40 is provided is not limited to the surface 31 of the heater base 3 but may be the side surface 34 or the bottom surface 12 of the heater base 3.

  As shown in FIG. 6, when the ground plate 30 is joined with the heater 15 and the bolt 40, the ground plate 30 extends between the heater base 3 and the heater 15, so that the heater base 3 and the heater are heated at high temperatures. 15 can be prevented from being formed, and similarly to the above-described embodiment, the occurrence of corrosion can be prevented, and the occurrence of abnormal discharge due to an increase in contact resistance can be prevented. Can be prevented. As a result, stable film formation can be performed.

  Further, in the present embodiment, the case where the concave portion 55 is provided on the heater base 3 side and the gap closing coil 60 is disposed has been described. However, the concave portion may be provided on the heater 15 side and the gap closing coil 60 may be provided. .

  In the present embodiment, when the film is formed, the substrate 10 side is set to the ground potential and the RF power source 109 is connected to the electrode flange 4 side. However, the electrode flange 4 side is set to the ground potential, and the substrate is You may employ | adopt for the film-forming apparatus which connects a power supply to 10 side and forms a film.

It is a schematic block diagram of the film-forming apparatus in embodiment of this invention. It is the A section enlarged detail drawing of FIG. It is a perspective view which shows the attachment state of the earth plate in embodiment of this invention. The plate biasing coil or gap closing coil in the embodiment of the present invention is shown, (A) is a plan view, (B) is a partial side view. It is the A section enlarged detail drawing of Drawing 1 showing another mode in an embodiment of the present invention. It is the A section enlarged detail drawing of Drawing 1 showing another mode in an embodiment of the present invention. It is a schematic block diagram of the conventional film-forming apparatus. It is the B section enlarged detail drawing of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Film-forming apparatus 2 ... Vacuum chamber (chamber) 3 ... Heater base (table) 10 ... Substrate 15 ... Heater (table) 30 ... Earth plate (plate member) 40 ... Bolt 44 ... Head 46 ... Shaft part 50 ... Plate Coil for energizing 60 ... Coil for closing gap 61 ... Central axis

Claims (10)

A chamber configured to introduce an AC voltage by introducing a film forming material gas;
A heater arranged in the chamber and configured to be capable of mounting a substrate;
In a film forming apparatus including a heater base configured to be able to place the heater,
A film forming apparatus, wherein a gap closing coil having an annular central axis along the peripheral edge of the heater is interposed between the heater and the heater base. A chamber configured to introduce an AC voltage by introducing a film forming material gas;
In a film forming apparatus provided with a table disposed in the chamber and configured to be capable of mounting a substrate,
The table is configured to be movable up and down,
In order to hold the chamber and the table at the same potential, a plate member having flexibility and conductivity is joined to the chamber and the table,
The film forming apparatus, wherein the plate member is urged against the table by a plate urging coil having an annular central axis arranged in parallel with the plate member. A chamber configured to introduce an AC voltage by introducing a film forming material gas;
In a film forming apparatus provided with a table disposed in the chamber and configured to be capable of mounting a substrate,
The table is configured to be movable up and down,
In order to hold the chamber and the table at the same potential, a plate member having flexibility and conductivity is joined to the chamber and the table,
The plate member is urged against the table by a plate urging coil having an annular central axis arranged in parallel with the plate member,
The table includes a heater configured to be able to mount the substrate, and a heater base configured to be able to mount the heater.
A film forming apparatus, wherein a gap closing coil having an annular central axis along the peripheral edge of the heater is interposed between the heater and the heater base.   The film forming apparatus according to claim 1, wherein the chamber is configured to be able to introduce a cleaning gas for removing deposits inside the chamber. The central axis of the plate biasing coil is disposed so as to surround a shaft portion of a bolt that joins the plate member to the table,
The film forming apparatus according to claim 2, wherein the plate urging coil is interposed between a head portion of the bolt and the plate member. The table includes a heater configured to be able to mount the substrate, and a heater base configured to be able to mount the heater.
The film forming apparatus according to claim 2, wherein the plate member is biased to the heater base by the plate biasing coil and joined to the heater base. The table includes a heater configured to be able to mount the substrate, and a heater base configured to be able to mount the heater.
The plate member is biased to the heater base by the first plate biasing coil and joined to the heater base, and is biased to the heater by the second plate biasing coil. The film forming apparatus according to claim 2, wherein the film forming apparatus is bonded to the heater.   The film forming apparatus according to claim 5, wherein the bolt is made of a nickel alloy.   9. The film forming apparatus according to claim 2, wherein the plate biasing coil is made of a nickel alloy.   The film forming apparatus according to any one of claims 1, 3, 4, 5, 6, 7, 8, and 9, wherein the gap closing coil is made of a nickel alloy.

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