Patent Publication Number: US-6700089-B1

Title: Plasma processing device, its maintenance method, and its installation method

Description:
TECHNICAL FIELD 
     The present invention relates to a plasma processing device, and a maintenance method and an installation method thereof. 
     BACKGROUND ART 
     Plasma processing devices are widely used during the process of manufacturing semiconductor devices in the prior art. A plasma processing device includes an upper electrode and a lower electrode facing opposite each other inside an air-tight processing chamber. During the process, high-frequency power is applied to the upper electrode to generate plasma from a processing gas induced into the processing chamber. Thus, a specific type of plasma process is implemented on a workpiece placed on the lower electrode. 
     An upper electrode unit at which the upper electrode is provided assumes a complex structure having a shield box in which a power supply member such as a power supply rod for supplying the high-frequency power to the upper electrode is housed, a matching box in which a matcher and the like are housed, a processing gas supply system and the like assembled as an integrated unit. Accordingly, the upper electrode unit as a whole becomes large and heavy. 
     This necessitates the operator to perform maintenance work such as cleaning the upper electrode and the inside of the processing chamber after disassembling the upper electrode unit into members with weights and in sizes that allow for easier handling. In addition, when the maintenance work is completed, the individual members must be reassembled into the upper electrode unit. 
     As described above, the device must be disassembled and reassembled each time maintenance work is performed in the prior art. This poses a problem of lowered device operating efficiency. In addition, the disassembled members must be accurately aligned during the reassembly process. Such a process is bound to be complicated and time-consuming. The shield box and the matching box are normally set at high positions that are hard for the operator to access. As a result, the operator is forced to assume an uncomfortable posture when mounting or dismounting the members. Thus, there is a problem in that a great onus is placed on the operator. 
     In addition, numerous piping systems and wirings such as a processing gas supply system, and an evacuating system, a cooling water circulating system and a power supply system are usually connected to the processing device. When installing such a processing device at a semiconductor manufacturing plant or the like, it is crucial to reduce the length of time required for the installation work by efficiently connecting the piping systems and the wirings. However, the pipings and the wirings are connected after delivering the device to the installation site. 
     The present invention has been completed by addressing the problems of the prior art discussed above. An object of the present invention is to provide a new and improved plasma processing device that addresses the problems discussed above and problems other than those discussed above and a maintenance method and an installation method thereof. 
     DISCLOSURE OF THE INVENTION 
     In order to achieve the object described above, in a first aspect of the present invention, a plasma processing device having a processing chamber in which a plasma process is implemented on a workpiece and an upper electrode unit constituting the upper wall of the processing chamber, which is characterized in that the upper electrode unit is capable of vacuum-locking the processing chamber by using its own weight and the difference between the pressure inside the processing chamber and the pressure outside the processing chamber without having to employ a means for locking, is provided. 
     According to the present invention, the upper electrode unit vacuum locks the processing chamber without utilizing a means for locking. When this structure is adopted, the processing chamber can be opened by simply removing the upper electrode unit. In addition, by placing the upper electrode unit on the processing chamber and reducing the pressure inside the processing chamber to a pressure lower than the pressure outside the processing chamber, the upper electrode unit is placed in air-tight contact with the wall of the processing chamber due to the weight of the upper electrode unit and the difference between the pressure inside the processing chamber and the pressure outside the processing chamber. As a result, a high degree of air-tightness is assured inside the processing chamber. As described above, the processing chamber can be opened and then sealed easily and quickly. Consequently, the onus on the operator is reduced and, in addition, the length of time required for performing maintenance inside the processing chamber is reduced as well. 
     In a second aspect of the present invention, a plasma processing device having a processing chamber in which a plasma process is implemented on a workpiece and an upper electrode unit constituting the upper wall of the processing chamber, which is characterized in that the upper electrode unit is constituted of a plurality of assemblies including, at least, one assembly capable of vacuum-locking the processing chamber by using its own weight and the difference between the pressure inside the processing chamber and the pressure outside the processing chamber without having to employ a means for locking and another assembly on which the one assembly can be placed, is provided. 
     According to the present invention, the upper electrode unit is constituted of a plurality of members to facilitate work performed by the operator. Thus, the heavy upper electrode unit can be disengaged in separate parts. This structure further reduces the onus placed on the operator. In addition, the one assembly is placed on the other assembly. As a result, the weight of the one assembly in addition to the difference between the pressure inside the processing chamber and the pressure outside the processing chamber allows the one assembly to be placed in air-tight contact with the other assembly. Consequently, the degree of air-tightness between the one assembly and the other assembly is improved. 
     It is desirable to include a first assembly having an electrode for supplying high-frequency power into the processing chamber or a grounded electrode, a second assembly that holds the first assembly and a third assembly having a high-frequency power supply path or a grounding path in the upper electrode unit. In this structure, the upper electrode unit is constituted of integrated assemblies that facilitate work performed by the operator. As a result, the upper electrode unit can be mounted and dismounted with ease and its maintenance is facilitated as well. 
     In addition, it is desirable to constitute the one assembly as the first assembly and the other assembly as the second assembly. This structure allows maintenance on the electrode to be performed with ease. 
     Under normal circumstances, the third assembly weighs more than the first assembly or the second assembly. For this reason, it is desirable to constitute the one assembly as the third assembly and the other assembly as the first assembly. When this structure is adopted, the processing chamber can be vacuum-locked with a higher degree of reliability by using the weight of the third assembly. 
     In a third aspect of the present invention, a plasma processing device having a processing chamber in which a plasma process is implemented on a workpiece and an upper electrode unit constituting the upper wall of the processing chamber, which is characterized in that a removing mechanism utilized to disengage the upper electrode unit from the processing chamber is provided, in that the upper electrode unit is constituted of a plurality of assemblies and in that the removing mechanism is capable of disengaging at least one assembly among the plurality of assemblies by itself and also capable of disengaging at least two assemblies among the plurality of assemblies together as an integrated member, is provided. 
     In this structure, an assembly that is harder for the operator to work on, for instance, can be disengaged by employing the removing mechanism. As a result, the onus placed on the operator is reduced. In addition, depending upon the type of maintenance being performed, an assembly can be disengaged by itself or a plurality of assemblies can be disengaged together as necessary. Consequently, the maintenance work can be performed with a high degree of efficiency within a short period of time. 
     It is desirable to allow at least one assembly to be mounted detachably at the processing chamber by employing a first locking mechanism. In this structure, by opening/closing the first locking mechanism, the one assembly can be mounted/dismounted with ease. In addition, the position of the one assembly can be determined by the first locking mechanism. As a result, the one assembly can be set in air-tight contact at the processing chamber with a high degree of reliability. Thus, a high degree of air-tightness is assured inside the processing chamber. 
     In addition, it is desirable to allow at least two assemblies to be detachably assembled with each other by employing a second locking mechanism. In this structure, the individual assemblies can be mounted/dismounted and their positions can be determined with ease and accuracy. Furthermore, by locking the second locking mechanism, the two assemblies can be mounted/dismounted as an integrated unit. When the second locking mechanism is released, either one of the assemblies can be mounted/dismounted by itself. 
     It is desirable to include a first assembly having an electrode for supplying high-frequency power into the processing chamber or a grounded electrode, a second assembly that holds the first assembly and a third assembly having a high-frequency power supply path or a grounding path in the upper electrode unit. 
     In a fourth aspect of the present invention, a method for performing maintenance on a plasma processing device having a processing chamber in which a plasma process is implemented on a workpiece, an upper electrode unit constituting the upper wall of the processing chamber and a removing mechanism used to disengage the upper electrode unit from the processing chamber with the upper electrode unit having at least a first assembly, a second assembly and a third assembly, which comprises a step in which the third assembly is secured to the removing mechanism and is disengaged, a step in which the first assembly is disengaged without using the removing mechanism, a step in which the third assembly and the second assembly are assembled together as an integrated unit, a step in which the third assembly coupled with the second assembly is secured to the removing mechanism and is disengaged and a step in which maintenance work is performed on at least one of; the first assembly, the second assembly, the third assembly and the processing chamber, is provided. 
     According to the present invention, after disengaging the large third assembly with relatively great weight which includes, for instance, a power supply path through which the high-frequency power is supplied or a grounding path with the removing mechanism, the relatively small first assembly with relatively little weight which includes, for instance, an electrode for supplying the high-frequency power into the processing chamber or a grounded electrode can be disengaged. Thus, the operator can perform maintenance on, for instance, the first assembly through a simple operation without having to disassemble the upper electrode unit into separate parts. In addition, after disengaging the first assembly, the second assembly having relatively great weight and a relatively large size that holds the first assembly, for instance, can be disengaged together with the third assembly by utilizing the removing mechanism. As a result, maintenance work can be performed inside the processing chamber, for instance, through a simple operation and the onus on the operator can be reduced. Furthermore, the reassembly process to be performed when the maintenance work is completed is facilitated. 
     In a fifth aspect of the present invention, a method for performing maintenance on a plasma processing device having a processing chamber in which a plasma process is implemented on a workpiece, an upper electrode unit constituting the upper wall of the processing chamber and a removing mechanism used to disengage the upper electrode unit from the processing chamber with the upper electrode unit having at least a first assembly and a second assembly, which comprises a step in which the first assembly is secured to the removing mechanism and is disengaged, a step in which the second assembly is disengaged without using the removing mechanism, a step in which maintenance work is performed on the disengaged second assembly, a step in which the second assembly having been serviced is reinstalled to the original position without using the removing mechanism and a step in which the first assembly secured to the removing mechanism is reinstalled to the original position, is provided. 
     According to the present invention, after the first assembly which includes, for instance, a supply path through which the high-frequency power is supplied or a grounding path is disengaged by using the removing mechanism, the second assembly that includes, for instance, an electrode for supplying the high-frequency power into the processing chamber or a grounded electrode can be disengaged. Thus, the second assembly can be serviced through a simple operation. In addition, after remounting the second assembly having undergone the maintenance process, the first assembly can be reinstalled at the original mounting position by using the removing mechanism. As a result, the onus placed on the operator after the maintenance work on the second assembly is completed is reduced. 
     In a sixth aspect of the present invention, a plasma processing device having a processing chamber in which a plasma process is implemented on a workpiece and a base frame on which the processing chamber is set, which is characterized in that the base frame includes a link piping having a means for switching and in hat the piping type links a pipe connected to a fluid supply source from which a fluid to be used in the processing chamber is supplied to a pipe connected to the processing chamber, is provided. 
     According to the present invention, the link piping is provided in the base frame. Thus, before the main device is installed, e.g., while the main device is being manufactured, the installation of the base frame and the piping work between the link piping at the base frame and the supply source can be completed. Then, the final piping process can be performed simply by connecting the link piping and the processing chamber through piping after installing the device at the base frame. As a result, the piping process is facilitated and also a reduction in the length of time required for the installation is achieved. In addition, as long as the means for switching is closed, the fluid does not leak even if the fluid is supplied to the link piping in advance prior to the installation of the main device. Consequently, the fluid can be supplied promptly after the piping becomes connected to the processing chamber. This means that the device is allowed to enter an operating state without a great delay. It is to be noted that the processing chamber as referred to in this description includes all the spaces at various devices installed on the base frame and used during the semiconductor manufacturing step during which various types of pipings become connected, including the delivery chamber of the delivery device which delivers the workpiece, as well as the processing chamber itself, in which the plasma process is implemented on the workpiece. Furthermore, the fluid as referred to in the description may be any substance distributed via a piping including a gas such as a processing gas or a liquid such as cooling water. 
     It is also desirable to provide a link wiring having an on/off means at the base frame, to link a wiring connected to a power source that provides power to be applied to the plasma processing device to a wiring connected to the plasma processing device. By adopting this structure, the wirings can be connected in a manner similar to that with which the pipings are connected as described above. 
     In a seventh aspect of the present invention, a method for installing a plasma processing device having a processing chamber in which a plasma process is implemented on a workpiece and a base frame on which the processing chamber is placed with the base frame having a link piping provided with a means for switching and the link piping used to link a pipe connected to a fluid supply source from which a fluid to be used in the processing chamber is supplied to a pipe connected to the processing chamber, which comprises a first step in which the base frame is secured onto the base on which the processing chamber is placed, a second step implementation after the first step, in which the pipe connected to the fluid supply source from which the fluid to be used in the processing chamber is supplied is connected to the link piping, a third step implemented after the second step, in which the processing chamber is secured to the base frame and a fourth step implemented after the third step, in which the pipe connected to the processing chamber is connected to the link piping, is provided. 
     According to the present invention, the plasma processing device having the base frame can be installed speedily over a shorter period of time. 
     It is even more desirable to provide a link wiring having an on/off means at the base frame to link a wiring connected to a power source that provides power to be applied to the plasma processing device to a wiring connected to the plasma processing device, implement a step in which the wiring connected to the power source that provides the power to be applied to the plasma processing device is connected to the link wiring during the third step and implement a step in which the wiring connected to the plasma processing device is connected to the link wiring during the fourth step. Through this method, the wirings can be connected through a process similar to that implemented to connect the pipings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic sectional view of an etching device that may adopt the present invention; 
     FIG. 2 is an enlarged schematic sectional view of the upper electrode unit of the etching device shown in FIG. 1; 
     FIG. 3 schematically illustrates a step implemented to perform maintenance on the upper electrode and inside the processing chamber of the etching device shown in FIG. 1; 
     FIG. 4 schematically illustrates a step implemented to perform maintenance on the upper electrode and inside the processing chamber of the etching device shown in FIG. 1; 
     FIG. 5 schematically illustrates a step implemented to perform maintenance on the upper electrode and inside the processing chamber of the etching device shown in FIG. 1; 
     FIG. 6 schematically illustrates a step implemented to perform maintenance on the upper electrode and inside the processing chamber of the etching device shown in FIG. 1; 
     FIG. 7 schematically illustrates the base frame of the etching device in FIG. 1; 
     FIG. 8 is a schematic perspective of the base frame in FIG. 7; 
     FIG. 9 schematically illustrates a method for installing the etching device shown in FIG. 1; 
     FIG. 10 schematically illustrates the method for installing the etching device shown in FIG. 1; and 
     FIG. 11 schematically illustrates the method for installing the etching device shown in FIG.  1 . 
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     The following is a detailed explanation of the preferred embodiments of the plasma processing device and the methods for performing maintenance on and installing the plasma processing device according to the present invention, given in reference to the attached drawings. 
     First Embodiment 
     First, in reference to FIGS.  1 ˜ 6 , a first embodiment in which the plasma processing device and the maintenance method according to the present invention are adopted in a plasma etching device and a maintenance method thereof is explained. 
     (1) Overall Structure of Etching Device 
     The structure of an etching device  100  is briefly explained. As illustrated in FIG. 1, a processing chamber  102  is provided in a conductive processing container  104  which is formed in a roughly cylindrical shape with an open top. At the ceiling of the processing chamber  102 , an upper electrode unit  103  is mounted by assuring a high degree of air-tightness. A conductive lower electrode  108  is provided inside the processing chamber  102 . The lower electrode  108  is formed so as to allow a workpiece such as a semiconductor wafer (hereafter referred to as a “wafer”) W to be placed on it. In addition, the lower electrode  108  is internally provided with a coolant circulating passage  110 . Through the coolant circulating passage  110 , a coolant which cools the wafer W to sustain the temperature of the wafer W at a specific level circulates. 
     A detailed explanation is to be given later on the structure and the operation of the upper electrode unit  103  which constitutes the core of the present invention. It is to be noted that high frequency power output from a high frequency power source  134  is supplied to the upper electrode unit  103  via a matcher  138 . The high-frequency power may have a frequency of, for instance, 13.56 MHz. High-frequency power output from a high-frequency power source  140  is supplied to the lower electrode  108  via a matcher  142 . The frequency of the high-frequency power may be, for instance, 380 KHz. Through this power application, a processing gas induced into the processing chamber  102  is raised to plasma. As a result, a specific type of etching process is implemented on the wafer W with the plasma. 
     In addition, a shield ring  144  is provided inside the processing chamber  102 . The shield ring  144  constituted of a dielectric material such as quartz covers the ceiling of the processing chamber  102  excluding the upper electrode  124 . By assuming such a structure, it becomes possible to prevent the ceiling of the processing chamber  102  from becoming worn down by the impact of the plasma. It is to be noted that the shield ring  144  is fitted so as to interlock the outer edge of the shield ring  144  at a staged portion  104   a  formed at the inner edge of the top of the processing container  104 . 
     An evacuating baffle plate  126  is provided around the lower electrode  108 . The evacuating baffle plate  126  allows the gas inside the processing chamber  102  to be evacuated as necessary by a turbo-molecular pump  132  via a switching valve  128  and an evacuating quantity control valve  130 . 
     The etching device  100  in the embodiment is constituted of the main components described above. Next, a detailed explanation is given on the structure of the upper electrode unit  103  constituting the core of the present invention. 
     (2) Structure of Upper Electrode Unit 
     As illustrated in FIG. 2, the upper electrode unit  103  mainly comprises first˜third assemblies  202 ,  204  and  206 . It is to be noted that the first assembly  202  is constituted of the upper electrode  124 , a cooling plate  154  and a baffle plate  164 . The second assembly  204  is constituted of a supporting plate  146  and an insulator  158 . The third assembly  206  is constituted of a shield box  106 , a matching box  136 , a power supply rod  178  and an electro-body  172 . The following is an explanation of the structure adopted in each assembly. 
     (a) Structure of First Assembly 
     First, the structure adopted in the first assembly  202  is explained. The upper electrode  124  constituting the first assembly  202  may be formed by using, for instance, silicon or aluminum having undergone an anodizing treatment, and is formed in a roughly disk shape. In addition, a plurality of gas outlet holes  124   a  are formed at the upper electrode  124 . The processing gas is supplied into the processing chamber  102  through the gas outlet holes  124   a . The cooling plate  154  is mounted on top of the upper electrode  124  by using fastening members  156  such as screws or bolts. Through the cooling plate  154 , power is delivered to the upper electrode  124  and also the heat generated at the upper electrode  124  during the process is communicated to the electro-body  172  which is to be detailed later. The cooling plate  154 , which is constituted of, for instance, aluminum having undergone an anodizing treatment, is formed in a roughly cylindrical shape. A staged portion  154   a  is formed at the outer circumference of the cooling plate  154 . The staged portion  154   a  is formed so as to interlock with a staged portion  158   a  formed at the insulator  158  which is to be detailed later. A space in which the baffle plate  164  for diffusing the processing gas is to be housed is formed toward the top of the cooling plate  154 . 
     The baffle plate  164  is constituted of a first baffle plate  166  and a second baffle plate  168  each constituted of aluminum having undergone an anodizing treatment and formed in a roughly disk shape. In addition, the baffle plate  164  is fastened inside the upper space at the cooling plate  154  by fastening members  170 . Through holes  166   a  and  168   a  are formed respectively at the upper baffle plate  166  and the lower baffle plate  168 . In such a structure, the processing gas having travelled through the baffle plate  164  is supplied to the gas outlet holes  124   a  via gas supply paths  154   c  formed at the cooling plate  154 . 
     (b) Structure of Second Assembly 
     Next, the structure adopted in the second assembly  204  is explained. The supporting plate  146 , which is a component of the second assembly  204 , constitutes part of the ceiling of the processing chamber  102  and supports the first and third assemblies  202  and  206  provided over the processing chamber  102 . The supporting plate  146 , which is constituted of, for instance, aluminum having undergone an anodizing treatment, is formed in a roughly toroidal shape. In addition, the supporting plate  146  and the processing container  104  are detachably secured to each other by a first locking mechanism  200  such as a buckling mechanism. The first locking mechanism  200  also achieves a function of determining the position of the second assembly  204 . Thus, once the first locking mechanism  200  is secured, the second assembly  204  is positioned at a specific position on the processing chamber  102  and becomes secured. Such a structure simplifies the process of positioning the second assembly  204 . As a result, the second assembly  204  is mounted quickly. O rings  196  and  198  are provided between the supporting plate  146  and the processing container  104 . The O-ring  196  is provided to maintain air-tightness. The O-ring  198  assures electrical conductivity. 
     In addition, the insulator  158  is fitted at the inner edge of the supporting plate  146 . The insulator  158  is provided to insulate the first assembly  202  and the electro-body  172  constituting the third assembly  206  to be detailed later from the supporting plate  146 . The insulator  158 , which may be constituted of, for instance, ceramic, is formed in a roughly cylindrical shape so as to enclose the outer circumferences of the first assembly  202  and the electro-body  172 . The insulator  158  is detachably supported by the supporting plate  146  at its projecting portion  158   b  formed at the outer circumference of the insulator  158  that interlocks with the inner edge of the supporting plate  146 . In addition, an O-ring  162  is provided between the projecting portion  158   b  and the supporting plate  146 . The staged portion  158   a  is formed inside the insulator  158 . The staged portion  158   a  is provided to detachably support the first assembly  202  inserted at the insulator  158  by interlocking with the staged portion  154   a  formed at the cooling plate  154  mentioned earlier. Thus, once the first assembly  202  is inserted at the insulator  158 , the first assembly  202  is set at a specific position. An O-ring  160  is provided between the staged portion  154   a  and the stage portion  158   a.    
     (c) Structure of Third Assembly 
     The structure of the third assembly  206  is now explained. The shield box  106 , which is a component of the third assembly  206 , prevents the high-frequency power from leaking to the outside of the etching device  100 . The shield box  106 , which may be constituted of, for instance, stainless steel, is formed in a roughly cylindrical shape so as to enclose the periphery of the power supply rod  178 , the electro-body  172  and the first and second assemblies  202  and  204 . The shield box  106  also functions as a cover that covers the various mechanical units such as the first assembly  202 . 
     The shield box  106  is set on the supporting plate  146 . The shield box  106  is secured by a second locking mechanism  150 , which detachably locks the shield box  106  to the supporting plate  146 . The second locking mechanism  150  also achieves a function of determining the position of the third assembly  206 . Thus, once the second locking mechanism  150  is secured, the third assembly  206  is set at a specific position at the second assembly  204  and becomes secured. Such a structure facilitates the process of positioning the third assembly  206 . As a result, the third assembly  206  can be mounted quickly. In addition, the shield box  106  is grounded via the supporting plate  146  and the processing container  104 . 
     The matching box  136  is set on the shield box  106 . The matching box  136 , which may be constituted of, for instance, stainless steel, houses the matcher  138 . In addition, the matching box  136  is secured to the shield box  106  by fastening members  174 . At the bottom of the matching box  136 , an output unit  176  of the matcher  138 , which is constituted as a projection protruding into the shield box  106  is secured via an insulating member (not shown). The power supply rod  178  for communicating high-frequency power to the first assembly  202  is connected to the output unit  176 . 
     The power supply rod  178  may be constituted of, for instance, a stainless steel member formed in a roughly tubular shape. The power supply rod  178  is connected to the output unit  176  and an input unit  172   a  formed at the electro-body  172 . An electrically conductive multi-plane contact (not shown) achieving elasticity is provided between the power supply rod  178  and the output unit  176  and between the power supply rod  178  and the input unit  172   a . The output unit  176  of the matcher  138  is secured to the upper end of the power supply rod  178  via screws (not shown). The input unit  172   a  of the electro-body  172  is secured care the lower end of the power supply rod  178  via a pin or the like (not shown) in such a manner that a movement over approximately several mm is allowed along the vertical direction. When the third assembly  206  is set on the first assembly  202  in this structure, the electro-body  172  is placed in air-tight contact with the cooling plate  154  due to its own weight. As a result, a high degree of air-tightness is assured in the processing chamber  102 . 
     In addition, the cooling plate  154  is placed in air-tight contact with the insulator  158  by the weight of the electro-body  172  and the first assembly  202 . The insulator  158 , in turn, is placed in air-tight with the supporting plate  146  by the weight of the electro-body  172  and the first assembly  202  and also by its own weight. The supporting plate  146  is then placed in air-tight contact with the processing container  104  by the weight of the first and third assemblies  202  and  206  and the weight of the insulator  158  and also by its own weight. As a result, the individual members are placed in air-tight contact with each other to assure a high degree of air-tightness in the processing container  104 . By performing evacuation in the processing container  104 , an even higher degree of air-tight contact is achieved between the cooling plate  154  and the insulator  158 , between the insulator  158  and the supporting plate  146  and between the supporting plate  146  and the processing container  104  due to the difference between the air pressure inside the processing container  104  and the air pressure outside the processing container  104 . Consequently, the degree of air-tightness in the processing container  104  is further improved. 
     As explained earlier, the electro-body  172  is provided to deliver the high-frequency power to the first assembly  202 . The electro-body  172  may be a member achieved by forming anodized aluminum, for instance, in a roughly disk shape. The electro-body  172  is formed in a size which allows it to be housed within the insulator  158 . Thus, the outer circumference of the electro-body  172  becomes enclosed by the insulator  158  when it is mounted. 
     The electro-body  172  is internally provided with a gas supply path  172   b . As a result, when it is mounted, the processing gas supplied from a gas supply source  184  such as a fluorocarbon gas is supplied to the baffle plate  164  via a flow-regulating valve  188  and a switching valve  190  housed inside a gas box  186  and a switching valve  192 , a gas inlet  194  and the gas supply path  172   b  provided inside the shield box  106 . The electro-body  172  is also internally provided with a coolant circulating passage  172   c . Through the coolant circulating passage  172   c , the coolant circulates. The coolant absorbs the heat generated at the upper electrode  124  during the process. As a result, the temperature of the upper electrode  124  is sustained at a predetermined level. An O-ring  195  for sustaining the air-tightness and an electrically conductive O-ring  182  for assuring electrical conductivity are provided between the electro-body  172  and the cooling plate  154 . 
     (d) Structure of Removing Mechanism 
     Next, the removing mechanism  208  is explained. The removing mechanism  208  is provided to move the third assembly  206  by itself from its mounting position are to move the third assembly  206  and the second assembly  204  as an integrated unit from their mounting positions in order to disengage the third assembly  206  or the integrated unit constituted of the third assembly  206  and the second assembly  204  from the etching device  100 . The removing mechanism  208  comprises a plate unit  212 , an arm unit  214  and a drive shaft  216  which is connected to a drive mechanism (not shown). The plate unit  212  is fastened to the matching box  136  by fastening members  210 . The arm unit  214  supports the plate unit  212 . The drive shaft  216  causes the plate unit  212  to travel along the vertical direction or to rotate along the horizontal direction via the arm unit  214 . It is to be noted that the operation of the removing mechanism  208  and the structure adopted to achieve mounting/dismounting operations of the second and third assemblies  204  and  206  are to be detailed later. 
     (3) Structure Adopted to Allow Mounting/Dismounting of First˜Third Assemblies 
     Next, in reference to FIGS.  3 ˜ 6 , a detailed explanation is given on the structure adopted to allow mounting/dismounting of the first˜third assemblies  202 ,  204  and  206 . The explanation given below focuses on an example for performing maintenance on the upper electrode  124  and inside the processing chamber  102 . FIGS.  3 ( a ),  4 ( a ),  5 ( a ) and  6 ( a ) present schematic perspectives of the entire etching device  100 , whereas FIGS.  3 ( b ),  4 ( b ),  5 ( b ) and  6 ( b ) present an enlarged schematic sectional views of the area around the shield box  106 . 
     As shown in FIGS.  3 ( a ) and  3 ( b ), the plate unit  212  of the removing mechanism  208  is fastened to the matching box  136  by the fastening members  210 . Next, the second locking mechanism  150  which secures the shield box  106  to the supporting plate  146  is released. Then, the drive shaft  216  is raised and rotated by the drive mechanism (not shown). As a result, the third assembly  206  is also raised and rotated and thus the third assembly  206  moves away from the mounting position. It is to be noted that the third assembly  206  is constituted of the matching box  136 , the shield box  106 , the power supply rod  178  and the electro-body  172  as explained earlier. Through this procedure, the first and second assembly  202  and  204  become exposed. This procedure is enabled since the electro-body  172  of the third assembly  206  and the cooling plate  154  of the first assembly  202  are not secured to each other via screws or the like. 
     Next, a jig  218  is mounted at the cooling plate  154  housed inside the insulator  158  as shown in FIGS.  4 ( a ) and  4 ( b ). By using the jig  218 , the maintenance worker disengages the first assembly  202  by hand. It is to be noted that the first assembly  202  is constituted of the cooling plate  154 , the upper electrode  124  and the baffle plate  164  as explained earlier. Thus, only the second assembly  204  is left on the processing chamber  102 . A specific type of maintenance work is performed on the disengaged first assembly  202 . For instance, if reaction products and the like formed during the process are adhering to the upper electrode  124 , the upper electrode  124  should be cleaned. Or if the upper electrode  124  has become worn due to plasma collisions, the upper electrode  124  should be replaced. It is to be noted that when the first assembly  202  is serviced, the first assembly  202  is reinstalled into the original state by performing a procedure which is a reversal of the procedure described above. 
     Next, as shown in FIGS.  5 ( a ) and  5 ( b ), the drive shaft  216  is rotated and lowered while the first assembly  202  is still disengaged. Then, the third assembly  206  is mounted at the second assembly  204 , and the shield box  106  and the supporting plate  146  are secured by the second locking mechanism  150 . 
     In the next step, the first locking mechanism  200  securing the supporting plate  146  and the processing container  104  is released, as shown in FIG.  6 ( a ) and  6 ( b ). Then, the drive shaft  216  is rotated and moved upwards again to move the second assembly  204  away from its mounting position together with the third assembly  206 . As a result, the processing chamber  102  becomes opened. Then, the worker removes the shield ring  144  provided inside the processing chamber  102  to completely open up the processing chamber  102 . Next, the processing chamber  102  is serviced to, for instance, clean any matter adhering to the inner wall of the processing container  104 . During this process, the disengaged shield ring  144 , too, can be serviced. 
     When the specific maintenance work is completed, the first˜third assemblies  202 ,  204  and  206  are remounted through a procedure which is a reversal of the procedure described above. Namely, first, the shield ring  144  is fitted at a sidewall of the processing chamber  102  as shown in FIGS.  6 ( a ) and  6 ( b ). Next, the second and third assemblies  204  and  206  having been moved out of the way are placed upon the processing container  104 , as shown in FIGS.  5 ( a ) and  5 ( b ). In the next step, the supporting plate  146  is secured to the processing container  104  with the first locking mechanism  200 . Then, the second locking mechanism  150  is released to allow the third assembly  206  alone to move away from its mounting position. Next, as shown in FIGS.  4 ( a ) and  4 ( b ), the first assembly  202  is mounted at the second assembly  204 . In the following step, as shown in FIGS.  3 ( a ) and  3 ( b ), the third assembly  206  having been moved out of the way is mounted at the second assembly  204  to restore the state illustrated in FIG.  2 . Then, the shield box  106  and the supporting plate  146  are secured by employing the second locking mechanism  150 . Thus, the first˜third assemblies  202 ,  204  and  206  are remounted at the etching device  100 . 
     In the example described above, the upper electrode  124  and the processing chamber  102  are both serviced. However, the upper electrode  124  alone may be serviced as described below. Namely, the first assembly  202  is disengaged through steps equivalent to those in FIGS.  3 ( a ) and  3 ( b ) and FIGS.  4 ( a ) and  4 ( b ) explained earlier. Then, maintenance work is performed on the upper electrode  124  of the disengaged first assembly  202 . After the first assembly  202  has been serviced it is remounted at the second assembly  204 . During this process, by mounting a spare first assembly  202  which has already been serviced at the second assembly  204  instead of remounting the disengaged first assembly  202 , the length of time required for the maintenance work is reduced. Then, the third assembly  206  is mounted as illustrated in FIG. 2 to complete the maintenance process. 
     The embodiment assumes the structure described above. In this structure, the upper electrode unit  103  is constituted of three separate assemblies, i.e., the first˜third assemblies  202 ,  204  and  206 , that are each provided as an integrated unit. In addition, the second and third assemblies  204  and  206 , which are heavy and large, are moved by utilizing the removing mechanism  208 . Thus, the onus placed on the maintenance worker is reduced. Furthermore, the first assembly  202  is pulled upward off the second assembly  202 *[1] by the maintenance worker. This allows the operator to maintain a better work posture. Moreover, it is not necessary to mount or dismount the fastening members when mounting/dismounting the first˜third assemblies  202 ,  204  and  206 . Consequently, a great reduction is achieved in the length of time required for the maintenance work. 
     Second Embodiment 
     Next, an embodiment in which the base frame of the plasma processing apparatus and the installation method thereof according to the present invention are adopted in an etching device and an installation method thereof is explained in reference to FIGS.  7 ˜ 11 . 
     (1) Structure of Base Frame 
     As shown in FIG. 7, an etching device  100  is installed on a base on which various devices are installed, e.g., on a floor  352  of a clean room, together with a load lock device  362 , by utilizing a process ship (casters)  302  and a base frame  306 . The load lock device  362 , which connects the etching device  100  to a delivery device  364 , includes a delivery path through which a wafer W is delivered. The process ship  302  also functions as a supporting frame which supports the etching device  100  and the load lock device  362 . The process ship  302 , which is provided with detachable casters  370 , is allowed to move freely. 
     The base frame  306  supports the process ship  302  and the delivery device  364 . It is to be noted that the delivery device  364  may be installed on the floor  352  instead of on the base frame  306 . In addition, the base frame  306  should be constituted of a material such as a steel material that has sufficient strength to withstand the heavy load which includes the weight of the etching device  100 , the load lock device  362  and the delivery device  364  and should be formed in a rough frame shape, as illustrated in FIG.  8 . It is to be noted that while the base frame  306  is formed as an integrated unit in the sample shown in FIG. 8, it may be constituted of two or three separate parts instead. In addition, a staged portion  306   a  is formed at the base frame  306 . The staged portion  306   a  has a thickness smaller than the thickness at the remaining portion of the base frame  306 . This structure allows the process ship  302  to pass over the base frame  306 . 
     In addition, as shown in FIGS. 7 and 8, the base frame  306  is internally provided with or mounted with first˜fifth link pipings  308 ,  310 ,  312 ,  314  and  316 . By adopting this structure, the various pipes to be detailed later which are provided to supply specific types of gases and liquids to the etching device  100  can be connected instantly. The first˜fifth link pipings  308 ,  310 ,  312 ,  314  and  316  are pre-designed and pre-installed in conformance to the connecting positions at which the pipings are connected to the etching device  100 . 
     As illustrated in FIG. 7, a first feed pipe  116   a  and a second feed pipe  116   b  through which the coolant is supplied from a coolant tank (not shown) to the coolant circulating passage  110  are connected to the first link piping  308 . A first drain pipe  118   a  and a second drain pipe  118   b  through which the coolant is drained into the coolant tank from the coolant circulating passage  110  are connected to the second link piping  310 . A first gas supply pipe  322   a  and a second gas supply pipe  322   b  for supplying dry air from a gas supply source (not shown) to the etching device  100  are connected to the third link piping  312 . A third gas supply pipe  324   a  and a fourth gas supply pipe  324   b  through which an inert gas is supplied from a gas supply source (not shown) into the processing chamber  102  are connected to the fourth link piping  314 . A first evacuating pipe  330   a  and a second evacuating pipe  330   b  through which discharged gas is evacuated from the turbo-molecular pump  132  mentioned earlier to a dry pump (not shown) are connected to the fifth link piping  316 . 
     Switching valves  320 ,  326  and  328  each constituting a means for switching are provided respectively at the first link piping  308 , the third link piping  312  and the fourth link piping  314 . The switching valves  320 ,  326  and  328  are all internally mounted at the base frame  306 . In this structure, by leaving the switching valves  320 ,  326  and  328  in a closed state, the gases and the like can be supplied to the first, third and fourth by the link pipings  308 ,  312  and  314  before the etching device  100  is installed. As a result, the gas and the like can be promptly supplied after the etching device  100  is installed. 
     In addition, as shown in FIGS. 7 and 8, the gas box  186  explained earlier is secured at the base frame  306 . A sixth link piping  318  is provided at the gas box  186 . A fifth gas supply pipe  332   a  and a sixth gas supply pipe  332   b  through which the processing gas is supplied from the gas supply source  184  into the processing chamber  102  are connected to the sixth link piping  318 . A switching valve  330  internally mounted at the gas box  186  is provided at the sixth link piping  318 . It is to be noted that while only a single gas supply system is shown inside the gas box  186  in FIG. 7, a plurality of gas supply systems, the number of which corresponds to the number of gases constituting the processing gas to be supplied into the processing chamber  102  are provided in the gas box  186  in reality. 
     The base frame  306  is also internally provided with a link wiring  354  as shown in FIGS. 7 and 8. A first wiring  356   a  and a second wiring  356   b  through which power output from a source (not shown) is supplied to the etching device  100  are connected to the link wiring  354  as illustrated in FIG.  7 . In this structure, the wirings through which the power is supplied to the etching device  100 , too, can be connected instantly. Furthermore, the link wiring  354  is pre-designed and pre-installed in conformance to the position at which the wiring is connected at the etching device  100 . A switch  360  constituting an on/off means is provided at the link wiring  354 , as illustrated in FIG.  7 . The switch  360  is internally mounted at the base frame  306 . This structure allows power to be supplied to the link wiring  354  before the etching device  100  is installed as long as the switch  360  is turned off. As a result, it is possible to supply power promptly after the etching device  100  is installed. 
     It is to be noted that although not shown, link pipings and a link wiring structured roughly identically to those described above are provided in conjunction with the load lock device  362  as well at the base frame  306 . In addition, pipes for supplying and draining the fluids in a manner similar to that described above and a power supply source are connected to these link pipings and link wirings. A switching valve or a switch is provided at each of the link pipings and the link wiring as necessary as well. 
     (2) Method of Processing Device Installation 
     Next, the method of installing the etching device  100  is explained. First, as shown in FIGS. 7 and 9, the base frame  306  is secured to the floor  352  of the clean room by using earthquake-proof metal fixtures such as bolts. In addition, before installing the etching device  100  and the like, the first˜sixth pipes  116   a ,  118   b ,  322   a ,  324   a ,  332   a  and  330   b  connected to the gas/liquid supply sources and the fluid source constituted of a vacuum pump and the first wiring  356   a  connected to the power supply source are buried under the floor of the clean room, for instance, as shown in FIGS. 7 and 8. Then, the first˜sixth pipes  116   a ,  118   b ,  322   a ,  324   a ,  332   a  and  330   b  and the first wiring  35   a  are respectively connected to the first˜sixth link pipings  308 ,  310 ,  312 ,  314 ,  316  and  318  and the link wiring  354 . 
     Next, as shown in FIG. 9, the delivery device  364  is set on the base frame  306 . It is to be noted that if the delivery device  364  is not to be installed on the base frame  306 , the delivery device  364  should be installed on the floor  352 . In addition, a delivery mechanism (not shown) which delivers the wafer W is provided inside the delivery device  364 . Subsequently, a cassette chamber  366  is connected to the delivery device  364 . The cassette (not shown) to house the wafer W is provided inside the cassette chamber  366 . 
     Next, the process ship  302  is moved close to the base frame  306 . At this point, the etching device  100  and the load lock device  362  are set on the process ship  302  in a connected state. Then, as illustrated FIG. 10, the process ship  302  is set parallel to, for instance, the base frame  306 . In the next step, the process ship  302  is aligned so as to allow the delivery device  364  to be connected with the load lock device  362  as shown in FIG.  11 . Afterward, an elevator mechanism  372  connected to the casters  370  is lowered to set the process ship  302  on the base frame  306 . Next, the casters  370  are taken off and the process ship  302  is secured to the base frame  306  with the earthquake proof metal fixture and the like. It is to be noted that the process ship  302  may be secured to the floor  352  instead. In addition the load lock device  362  is connected to the delivery device  364 . 
     Then, as illustrated in FIG. 7, the pipes  116   b ,  118   a ,  322   b ,  324   b ,  332   b  and  330   a  and the second wiring  356   b  already connected to the etching device  100  are respectively connected to the first˜sixth link pipings  308 ,  310 ,  312 ,  314 ,  316  and  318  and the link wiring  354 . During this process, the individual connections are made via a through opening  302   a  provided at the process ship  302 . 
     The embodiment adopting the structure described above allows the base frame  306 , which is provided to support the etching device  100  and the like, to be secured to the base before the etching device  100  and the like are brought to the installation site, e.g., while the etching device  100  and the like are being manufactured. In addition, the pipes  116   a ,  118   b ,  322   a ,  324   a ,  332   a  and  330   b  on the fluid source side which require difficult piping work can be laid out and connected to the first˜sixth link pipings  308 ,  310 ,  312 ,  314 ,  316  and  318  in advance during the production. As a result, the length of time to elapse between the installation of the etching device  100  and the like and the start of the actual operation is greatly reduced. Furthermore, as long as the switching valves  320 ,  326 ,  328  and  330  remain closed, the gases and the like do not leak before the etching device  100  is connected. 
     While the invention has been particularly shown and described with respect to preferred embodiments thereof by referring to the attached drawings, the present invention is not limited to these examples and it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit, scope and teaching of the invention. 
     For instance, while an explanation is given above in reference to the first embodiment on an assumption that the upper electrode unit is constituted of the first˜third assemblies and that specific members such as the cooling plate and the like are included in the individual assemblies, the present invention is not restricted by these details. The present invention may be adopted when the number of assemblies is two or four or more or when members included in the individual assemblies are different from those in the embodiment, as well. 
     In addition, while an explanation is given above in reference to the first embodiment on an example in which the position of the second assembly is set by utilizing the first locking mechanism, the present invention is not limited to this example. For instance, the second assembly can be set at a specific position by fitting an indentation and/or a projection formed at the lower surface of the supporting plate with a projection and/or an indentation formed at the top surface of the processing container, without having to utilize the first locking mechanism. It is to be noted that in such a case, too, a high degree of air-tightness is maintained at the processing container due to the weight of the assemblies and the difference between the pressure inside the processing chamber and the pressure outside the processing chamber. 
     While an explanation is given above in reference to the first embodiment on a structural example that adopts the first and second locking mechanisms each constituted of a buckling mechanism, the present invention is not restricted by these structural details. The present invention may be adopted in conjunction with locking mechanisms constituted of other mechanisms as long as the second assembly and the processing container or the second assembly and the third assembly can the positioned relative to each other and secured. 
     Also, while an explanation is given above in reference to the first embodiment on a structural example in which the insulator is supported by the supporting plate, the present invention is not restricted by these details either. The present invention may be adopted by, for instance, securing the insulator to the supporting plate via a retaining member as well. 
     While an explanation is given above in reference to the first embodiment on a structural example in which the removing mechanism is secured to the matching box only for maintenance, the present invention is not limited to this example. The present invention may be implemented by leaving the removing mechanism and the matching box in a locked state at all times instead. 
     While an explanation is given above in reference to the first embodiment on an example in which high-frequency power is applied to the upper electrode, the present invention is not limited to this example. The present invention may be adopted in conjunction with an upper electrode that constitutes a ground electrode, instead. 
     While an explanation is given above in reference to the first embodiment on a structural example in which the electrobody, the power supply rod and the like constitute a power supply path, the present invention is not restricted to these structural details. The present invention may be instead implemented by constituting a grounding path with the electro-body, the power supply rod and the like. 
     In addition, while an explanation is given above in reference to the second embodiment, on a structural example in which link pipings for supplying specific gases or fluids are provided at the base frame, the present invention is not restricted to such structural details. The present invention may be implemented by providing a link piping through which any type of fluid required in a plasma processing device is supplied at the base frame. Furthermore, the number of link pipings and the number of link wirings provided at the base frame can be adjusted as necessary in conformance to the design of a given processing device. 
     While an explanation is given above in reference to the second embodiment on an example in which the link pipings and the link wiring are internally provided or externally mounted at specific positions of the base frame, the present invention is not restricted to these details. The present invention may be implemented by internally providing or externally mounting the link pipings and the link wiring as appropriate at the base frame in conformance to the design of a given processing device. 
     While an explanation is given above in reference to the second embodiment on a structural example in which a unit achieved by connecting the load lock device to the etching device is connected to the delivery device, the present invention is not restricted to these details, and it may be adopted when installing a single processing device or a plurality of various processing devices each requiring link pipings and link wirings to be connected thereto in a connected state. 
     Furthermore, while an explanation is given in reference to the first and second embodiments on an example in which the present invention is adopted in a plane parallel plate etching device, the present invention is not limited to this example. The present invention may be adopted in any of various types of plasma processing devices including magnetron plasma processing devices and inductively coupled plasma processing devices as well. In addition, the present invention may be adopted in an apparatus that performs various types of plasma processing including ashing and film formation processing. Moreover, it may be adopted in an apparatus that performs processing on a glass substrate to constitute an LCD. 
     The present invention makes it possible for the maintenance worker to assume a better work posture while performing maintenance work on the electrode or inside the processing chamber. In addition, the heavy and large members do not need to be mounted or dismounted by the maintenance worker. As a result, the onus placed on the worker is reduced. Furthermore, the work process to be carried out by the maintenance worker is greatly simplified and thus, the length of time required for the maintenance work is reduced. In addition, in another aspect of the present invention, the length of time to elapse between the plasma processing device installation and the start of the actual operation of the device is reduced. Thus, the production of can be started promptly. 
     INDUSTRIAL APPLICABILITY 
     The present invention can be adopted in a plasma processing device and, more specifically, in a plasma etching device, a plasma ashing device and a plasma CVD (chemical vapor deposition) device. 
     Amendments 
     The electro-body  172  is internally provided with a gas supply path  172   b . As a result, when it is mounted, the processing gas supplied from a gas supply source  184  such as a fluorocarbon gas is supplied to the baffle plate  164  via a flow-regulating valve  188  and a switching valve  190  housed inside a gas box  186  and a switching valve  192 , a gas inlet  194  and the gas supply path  172   b  provided inside the shield box  106 . The electro-body  172  is also internally provided with a coolant circulating passage  172   c . Through the coolant circulating passage  172   c , the coolant circulates. The coolant absorbs the heat generated at the upper electrode  124  during the process. As a result, the temperature of the upper electrode  124  is sustained at a predetermined level. An O-ring  195  for sustaining the air-tightness and an electrically conductive O-ring  182  for assuring electrical conductivity are provided between the electro-body  172  and the cooling plate  154 . 
     EXPLANATION OF REFERENCE NUMERALS 
       100  etching device 
       102  processing chamber 
       103  upper electrode unit 
       106  shield box 
       108  lower electrode 
       124  upper electrode 
       134  high frequency source 
       136  matching box 
       138  matcher 
       146  supporting plate 
       150  second locking mechanism 
       154  cooling plate 
       158  insulator 
       164  baffle plate 
       172  electro-body 
       178  power supply rod 
       200  first locking mechanism 
       202  first assembly 
       204  second assembly 
       206  third assembly 
       208  removing mechanism 
       306  base frame 
       308 ,  310 ,  312 ,  314 ,  316 ,  318  first˜sixth link pipings 
       320 ,  326 ,  328 ,  330  switching valve 
       354  link wiring 
       360  switch 
     W wafer