JP2009161822A - Plasma treatment device, and plasma treatment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma treatment device where heating treatment and plasma treatment to a substrate in a film deposition stage can be continuously performed in the same position, and to provide a plasma treatment method. <P>SOLUTION: The plasma treatment device includes: a cylindrical earth shield 4 arranged between a substrate 6 and a metallic sheet 3 for a plasma electrode; and shielding plates 5 (5a, 5b) movably provided in the vicinity of the edge part on the side of the substrate in the earth shield 4 and whose surfaces are subjected to blackening treatment. In the case plasma treatment is not performed, each shielding plate 5 covers the opening part of the earth shield 4, and shields the space between the metal plate 3 for a plasma electrode and the substrate 6, thus the substrate 6 can be subjected to the heating treatment with each shielding plate 5 heated by plasma discharge. Further, upon plasma treatment, the shielding plates 5a, 5b move to open the opening part of the earth shield 4, thus plasma treatment can be performed to the surface of the substrate 6 facing the metallic plate 3 for a plasma electrode without moving the substrate even after heating treatment. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a plasma processing apparatus and a plasma processing method capable of continuously performing heating of a substrate using plasma discharge and plasma processing of the substrate.

  In a substrate surface treatment process by a conventional plasma discharge method, usually, before the plasma treatment is performed on the substrate, pretreatment such as drying or surface modification is performed by heating the substrate with a heater in a vacuum chamber. At that time, in order to process the substrate at the same position, after the pre-treatment of the substrate, the heater and the plasma discharge electrode are replaced, or if the substrate is movable, the plasma surface of the substrate by plasma discharge. A process such as moving the substrate to a position for processing is required.

  Therefore, the apparatus is increased in size by the replacement means of the heater and the plasma discharge electrode, the transport means for moving the substrate, and the equipment cost is also increased. Further, there has been a problem that the plasma processing operation becomes complicated due to the switching operation of the heater for drying the substrate and the electrode for plasma discharge or the transfer operation of the substrate.

  On the other hand, in JP-A-2004-43880 (Patent Document 1), a plurality of vapor deposition sources are provided in a vacuum vessel, and a shielding plate with a devised shape is arranged between the vapor deposition source and the substrate, so that As compared with a thin film formed using a vapor deposition source, a method for improving the uniformity of the film thickness and refractive index of the thin film formed on the substrate has been proposed.

  In addition, in JP-A-5-279845 (Patent Document 2), a shielding plate disposed around a target and a substrate in a vacuum vessel is configured to have a heating element or a heating element as a component. In addition, a method has been proposed in which temperature control is performed by connecting a power source to the shielding plate to suppress the internal stress of the thin film adhering to the shielding plate and to reduce scattering of foreign matter.

In this method, the temperature of the shielding plate is maintained at the time of thin film formation, so that the thermal stress component of the thin film adhering to the shield plate cooled after the thin film formation is controlled so as to cancel out the intrinsic stress component. It is possible to control the stress range so that no occurrence occurs. In addition to the Pt—Rh alloy, the heat generating material may be an Ni-based alloy containing Cr as a main alloy element, an Fe-based alloy containing Cr, Al, or Co as an alloy element, or an alloy containing Cr, Al, or Ti. Fe-based alloys as elements have been proposed.
JP 2004-43880 A JP-A-5-279845

  In view of the above-described conventional circumstances, the present invention provides a substrate heat treatment and plasma treatment before forming a thin film without changing the position of the substrate or the heater and the plasma electrode in the plasma surface treatment step of the substrate using plasma discharge. It is an object of the present invention to provide a plasma processing apparatus and a plasma processing method that can be continuously performed at the same position.

  In order to achieve the above object, a plasma processing apparatus provided by the present invention is a plasma processing apparatus in which a substrate held by a substrate holder in a processing chamber is opposed to a plasma electrode and plasma processing is performed on the substrate by plasma discharge. A cylindrical earth shield whose central axis is disposed between the electrode and the plasma electrode in a direction perpendicular to both, and a shield plate that is movably provided in the vicinity of the substrate side end of the earth shield and has a blackened surface. When the plasma treatment is not performed, the shield plate covers the opening of the earth shield to shield between the plasma electrode and the substrate, and the substrate is heated with the shield plate heated by plasma discharge. The shielding plate is moved to open the opening of the earth shield, and the plasma processing is performed on the substrate facing the plasma electrode.

  In the plasma processing apparatus of the present invention, a preferred embodiment of the shielding plate is divided into two parts, and one end of each is attached to the substrate side end of the earth shield, and when the plasma treatment is not performed, the opening of the earth shield The plasma electrode and the substrate are covered and shielded between the plasma electrode and the substrate, and moved to the square cylindrical inner peripheral surface side of the earth shield during the plasma processing, and the plasma electrode and the substrate are opposed to each other. .

  The plasma processing method provided by the present invention is a plasma processing method in which a substrate held by a substrate holder in a processing chamber is opposed to a plasma electrode and plasma processing is performed on the substrate by plasma discharge, between the substrate and the plasma electrode. A cylindrical earth shield is arranged in the direction in which the central axis is orthogonal to both of them, and a shielding plate whose surface is blackened is provided in the vicinity of the substrate side end of the earth shield so that the shielding plate can move the earth shield. With the opening covered and the space between the plasma electrode and the substrate shielded, the substrate was heat-treated with a shielding plate heated by plasma discharge, and then the shielding plate was moved to open the ground shield opening. The plasma treatment is performed on the substrate facing the plasma electrode.

  In the plasma processing method of the present invention, the substrate heat treatment temperature by the shielding plate can be controlled by the amount of electric power applied to the plasma electrode in plasma discharge.

  According to the present invention, there is no need to change the position of the substrate or the heater and the plasma discharge electrode in the plasma surface treatment process of the substrate using plasma discharge, and the substrate is heated without performing plasma surface treatment by plasma discharge. Then, the substrate can be plasma treated at the same position.

  Therefore, by using the plasma processing apparatus or the plasma processing method according to the present invention, the substrate heat treatment before the thin film formation and the plasma treatment to the substrate can be continuously performed at the same position. It is possible to improve the efficiency of the apparatus, reduce the size of the apparatus, and reduce the equipment cost, which is extremely useful industrially.

  In the present invention, the structure of the electrode for plasma discharge of the plasma processing apparatus is improved, and the surface of the cylindrical earth shield disposed between the substrate and the plasma electrode is blackened near the substrate side end. A shielding plate is movably provided. When the plasma treatment is not performed, this shielding plate moves in the vicinity of the substrate so as to be substantially parallel to the substrate, and covers the opening of the cylindrical earth shield to shield between the plasma electrode and the substrate. Further, during the plasma processing, the opening of the earth shield is opened by moving the shielding plate, and the plasma electrode and the substrate can be opposed to each other inside the earth shield.

  By installing a movable shielding plate as described above, when plasma processing is not performed, the opening of the earth shield is covered with the shielding plate and the space between the plasma electrode and the substrate is shielded. However, no thin film is formed on the substrate. On the other hand, since the shielding plate is heated by plasma discharge, it is possible to heat-treat the substrate located substantially in the vicinity of the shielding plate by the radiant heat from the heated shielding plate. Further, during the plasma processing, the shielding plate moves to open the opening portion of the cylindrical earth shield, and the plasma electrode and the substrate are opposed to each other, so that the plasma processing gas can be introduced to perform the plasma processing on the substrate.

  The means for moving the shielding plate is not limited, and an open / close type or a slide type means can be used. Further, as the shielding plate, in order to heat the substrate with radiant heat, it is necessary to use a plate material whose surface is blackened so as to increase the emissivity and has good thermal conductivity. As a material of the shielding plate, a metal material satisfying the above conditions is preferable, but ceramics, a heat-resistant resin material, or the like may be used.

  For example, the surface of the metal material can be blackened by applying several μm of black nickel plating or black chrome plating. In particular, when aluminum is used, the surface can be black anodized, and when copper or a copper alloy is used, the surface can be oxidized and blackened by forming a copper oxide film. The surface blackened in this way exhibits an emissivity of about 0.95. As other blackening treatments, a method of applying a heat-resistant black paint on the surface and a method of sandblasting or etching the surface are possible. Other than the metal material, it is also possible to use a material having a high thermal conductivity such as carbon, which is black.

  Next, the plasma processing apparatus and the plasma processing method of the present invention will be described in detail with reference to the drawings. FIG. 1A is a cross-sectional view of the electrode portion for plasma discharge in the film forming apparatus of the present invention. A cooling water passage 2 is provided in the plasma electrode container 1 in the processing chamber of the apparatus, as in the conventional apparatus. The plasma electrode container 1 and the substrate holder 7 are arranged to face each other so as to be substantially parallel to each other. A plasma electrode metal plate 3 is fixed to the front surface of the plasma electrode container 1 by a fixing jig (not shown). There is an earth shield 4 at the periphery of the space between the plasma electrode metal plate 3 and the substrate 6 to be subjected to plasma treatment and the substrate holder 7 that holds the substrate 6, and between the substrate 6 and the plasma electrode metal plate 3. A shielding plate 5 is installed in the vicinity of the substrate in parallel with the substrate 6. The shielding plate 5 can be moved from between the plasma electrode metal plate 3 and the substrate 6 by a method such as opening / closing or sliding as required.

  Between the above-described plasma electrode metal plate 3 and the substrate 6, a cylindrical earth shield 4 for preventing the plasma formed on the plasma electrode metal plate 3 from spreading to the surroundings is centered on the plasma. It is arranged and fixed in a direction substantially orthogonal to the electrode metal plate 3 and the substrate 6. Accordingly, the plasma electrode metal plate 3 and the substrate 6 face each other through the opening formed inside the cylindrical earth shield 4 so as to be substantially parallel to each other. The outer shape of the cross section of the earth shield 4 is preferably substantially the same as that of the plasma electrode metal plate 3 or the substrate 6.

  Further, a shielding plate 5 whose surface is blackened is movably provided in the vicinity of the end of the earth shield 4 on the substrate 6 side. The illustrated shielding plate 5 is an open / close type that is divided into a shielding plate 5a and a shielding plate 5b, and one end of each of the shielding plate 5a and the shielding plate 5b is connected to the end of the earth shield 4 on the substrate 6 side, for example, a hinge or the like. It is attached so that it can be folded. When the plasma treatment is not performed, the shielding plate 5a and the shielding plate 5b cover the opening of the earth shield 4 to shield the plasma electrode metal plate 3 and the substrate 6 as shown in FIG. . On the other hand, at the time of plasma processing, as shown in FIG. 1B, the shielding plate 5 a and the shielding plate 5 b are moved and stored on the inner peripheral surface side of the square cylindrical shape of the earth shield 4, and within the opening of the earth shield 4. The plasma electrode metal plate 3 and the substrate 6 face each other.

  Therefore, in the plasma processing, the shielding plate 5a and the shielding plate 5b are moved and stored, the opening of the earth shield 4 is opened, and the plasma electrode metal plate 3 and the substrate 6 are opposed to each other. When the plasma processing is not performed, the stored shielding plate 5a and shielding plate 5b are opened to cover the opening of the earth shield 4. In this state, by applying power to the plasma electrode metal plate 3 and performing plasma discharge, the shielding plate 5 is heated from the plasma electrode side, and the substrate 6 is heat-treated by the radiant heat from the heated shielding plate 5. Can do. The heat treatment temperature of the substrate 6 by the shielding plate 5 can be controlled by the amount of electric power applied to the plasma electrode metal plate 3. At this time, since the space between the plasma electrode metal plate 3 and the substrate 6 is shielded by the shielding plate 5, the substrate 6 is not subjected to plasma treatment.

  FIG. 2 shows a specific example of a film forming apparatus provided with the above-described electrode portion for plasma discharge of the present invention. In this film forming apparatus, the electrode portion for plasma discharge shown in FIG. 1 is housed and installed in the processing chamber 9, and a vacuum pump 11 for evacuating the inside of the vacuum chamber (processing chamber) 9, plasma discharge A gas supply port and a discharge port (not shown) are provided. The substrate holder 7 can be equipped with a temperature control mechanism 10 having heating or cooling in order to control the temperature of the substrate 6.

  Various discharge modes such as direct current (DC), high frequency (RF), and alternating current (MF) can be used for the plasma treatment using the plasma discharge electrode of the film formation apparatus or the heat treatment of the substrate. Various substrates such as glass, ceramics, metals, plastics, and polymer films can be used as substrates that can be subjected to plasma surface treatment after the vacuum heat treatment using the plasma electrode of the present invention. . Further, the substrate holder 7 on which the substrate is mounted can be equipped with a heating or cooling temperature control mechanism 10 (see FIG. 2) for controlling the temperature of the substrate.

  Furthermore, the plasma processing apparatus of the present invention can be attached to various plasma processing apparatuses such as a batch type plasma processing apparatus, an inline type plasma processing apparatus, and a winding type plasma processing apparatus. For example, a plasma processing method when the plasma processing apparatus of the present invention is attached to a batch type plasma processing apparatus will be described.

For example, a plasma processing method of a batch type plasma processing apparatus to which the plasma processing apparatus of the present invention is applied will be specifically described with reference to FIGS. First, as shown in FIG. 2, a desired plasma electrode metal plate 3 is mounted on the plasma electrode container 1, and a substrate 6 is mounted on the substrate holder 7. Therefore, after the inside of the vacuum chamber 9 is evacuated by the vacuum pump 11, a plasma discharge gas such as O _{2 is} supplied to the plasma processing portion to maintain a predetermined pressure.

  Next, the shield plates 5a and 5b divided into two parts are inserted between the plasma electrode metal plate 3 and the substrate 6, and power is applied to the plasma electrode metal plate 3 while the opening of the earth shield 4 is shielded. The plasma discharge is supplied to cause plasma discharge, and the plasma discharge input power is adjusted so that the shielding plate 5 has a predetermined temperature. The shielding plate 5 is heated by the plasma discharge, and the substrate 6 is heated for a predetermined time by radiant heat from the heated shielding plate 5 to perform pretreatment. Thereafter, the plasma discharge is temporarily stopped, and the shielding plate 5 and the substrate 6 are allowed to cool, or the substrate 6 is controlled to a predetermined temperature using the temperature control mechanism 10 of the substrate holder 7.

  Subsequently, while keeping the vacuum state of the vacuum chamber 9, the two divided shielding plates 5 a and 5 b are moved from between the plasma electrode metal plate 3 and the substrate 6, folded and stored on the inner peripheral surface side of the earth shield 4. (See FIG. 3). In this state, power is supplied to the plasma electrode metal plate 3 to cause plasma discharge, the substrate 6 is subjected to a predetermined plasma surface treatment, and then the power supply to the plasma electrode metal plate 3 is stopped. Thereafter, the substrate 6 is cooled, a vacuum leak is performed, and the substrate 6 is taken out.

  In this way, the heat treatment of the substrate before the thin film formation and the plasma treatment to the substrate can be continuously performed at the same position without changing the position of the substrate or the heater and the plasma electrode, The efficiency of processing and operation can be improved, and the plasma processing apparatus can be downsized and the equipment cost can be reduced.

[Example 1]
The batch type plasma processing apparatus according to the present invention shown in FIG. 2 is used. After the polymer film substrate 6 is mounted on the substrate holder 7 of the processing apparatus, the inside of the vacuum chamber 9 is evacuated using the vacuum pump 11, and The inside of the vacuum chamber 9 was maintained at 13.3 Pa (100 mm Torr) by flowing O ₂ gas through the plasma electrode portion. The earth shield 4 is a square cylinder having substantially the same outer shape as the plasma electrode metal plate 3 and the substrate 6, and the shield plate 5 is divided into two shield plates 5a and 5b. The copper was blackened by black chrome plating.

  With the shielding plates 5 a and 5 b inserted between the plasma electrode metal plate 3 and the polymer film substrate 6, power was supplied to the plasma electrode metal plate 3 to perform plasma discharge. At that time, the plasma discharge input power was adjusted so that the polymer film substrate 6 was held at about 150 ° C. by the radiant heat from the shielding plates 5a and 5b, and the substrate 6 was heated for 5 minutes to perform a drying process.

  Next, the plasma discharge is stopped, the temperature of the substrate 6 is controlled to 5 ° C. using the temperature control mechanism 10 of the substrate holder 7, and the shielding plates 5 a and 5 b are folded while maintaining the vacuum state, thereby plasma electrode metal It was moved from between the plate 3 and the substrate 6 and stored on the inner peripheral surface side of the earth shield 4. Thereafter, power was supplied to the plasma electrode metal plate 3 to cause plasma discharge, and plasma treatment was performed for 10 minutes. Thereafter, the power supply to the plasma electrode metal plate 3 was stopped, the substrate 6 was cooled, and then a vacuum leak was performed to take out the substrate 6.

[Comparative Example 1]
The treatment was performed using an apparatus capable of performing the same treatment as in Example 1 except that a heater and a plasma electrode were separately provided and the substrate could be moved to each treatment zone. First, a polymer film substrate similar to that used in the example was mounted on the substrate holder of the apparatus, the inside of the vacuum chamber was evacuated using a vacuum pump, and then the substrate was placed at 150 ° C. by a heater facing the substrate. The pretreatment for heat drying was carried out for 5 minutes. After the heating and drying process is completed, the substrate is cooled, and further moved to the front surface of the plasma electrode using a moving mechanism of the substrate, and the temperature of the substrate is controlled at 5 ° C. to supply power to the plasma electrode. Plasma treatment was started and treatment was performed for 10 minutes. After the plasma treatment, power supply to the plasma electrode was stopped, the substrate was cooled, a vacuum leak was performed, and the substrate was taken out.

  In the apparatus for performing this operation, a space for installing the heater and the plasma electrode is required independently, and further, a mechanism for moving the substrate is required. Therefore, the apparatus is larger than the apparatus of the first embodiment. In addition, the equipment cost is also increased. Furthermore, there is a problem that the operation of each process becomes complicated.

It is a schematic sectional drawing which shows the principal part of the plasma processing apparatus of this invention. (A) The shield plate 5a, 5b divided into two is inserted between the metal plate 3 for plasma electrodes and the board | substrate 6, and the state which shielded the opening part of the earth shield 4 is shown. (B) The shield plate divided into two 5a and 5b are moved between the plasma electrode metal plate 3 and the substrate 6, folded and stored on the inner peripheral surface side of the earth shield 4, and the opening of the earth shield 4 is shown open. It is a schematic sectional drawing which shows one specific example of the plasma processing apparatus of this invention, and shows the state which heat-processes. It is a schematic sectional drawing which shows one specific example of the plasma processing apparatus of this invention, and shows the state which performs a plasma surface treatment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plasma electrode container 2 Cooling water channel | path 3 Metal plate for plasma electrodes 4 Earth shield 5 (5a, 5b) Shield plate 6 Substrate 7 Substrate holder 8 Deposition plate 9 Vacuum chamber 10 Temperature control mechanism 11 Vacuum pump

Claims (4)

  A plasma processing apparatus in which a substrate held by a substrate holder in a processing chamber is opposed to a plasma electrode and plasma processing is performed on the substrate by plasma discharge, and a central axis is disposed between the substrate and the plasma electrode in a direction perpendicular to both. A cylindrical earth shield and a shield plate that is movably provided in the vicinity of the substrate side end of the earth shield and has a blackened surface. When the plasma treatment is not performed, the shield plate is an opening of the earth shield. The substrate is shielded between the plasma electrode and the substrate, and the substrate is heated with a shield plate heated by plasma discharge. During the plasma treatment, the shield plate moves to open the opening of the earth shield and face the plasma electrode A plasma processing apparatus for performing plasma processing on a processed substrate.   The shielding plate is divided into two parts, and one end of each is attached to the substrate side end of the earth shield, and when the plasma treatment is not performed, covers the opening of the earth shield and shields between the plasma electrode and the substrate, 2. The plasma processing apparatus according to claim 1, wherein the plasma processing is stored by moving to the square cylindrical inner peripheral surface side of the earth shield so that the plasma electrode and the substrate face each other.   A plasma processing method in which a substrate held by a substrate holder in a processing chamber is opposed to a plasma electrode, and plasma processing is performed on the substrate by plasma discharge, and a cylindrical earth shield is interposed between the substrate and the plasma electrode with a central axis therebetween. Arranged in a direction orthogonal to each other, a shield plate whose surface is blackened is provided in the vicinity of the end of the earth shield on the substrate side. The shield plate covers the opening of the earth shield between the plasma electrode and the substrate. In the shielded state, the substrate is heated with a shield plate heated by plasma discharge, and then the shield plate is moved to open the ground shield, and the substrate facing the plasma electrode is subjected to plasma treatment. And a plasma processing method.   The plasma processing method according to claim 3, wherein the heat treatment temperature of the substrate by the shielding plate is controlled by the amount of electric power applied to the plasma electrode in plasma discharge.