JP5849232B2 - Plasma processing apparatus and plasma processing method - Google Patents

Description

  The present invention relates to a plasma processing apparatus and a plasma processing method.

  The plasma processing apparatus of Patent Literature 1 includes a transport carrier including an adhesive sheet to which an object (for example, a wafer or a semiconductor substrate) for plasma processing such as dicing and cleaning is attached, and a frame to which the adhesive sheet is attached. This carrier is placed on the stage of the plasma processing unit, and the object is plasma processed. The plasma processing apparatus also includes a cover that covers the frame and the adhesive sheet (region between the object and the frame) during the plasma processing. By shielding the frame and the adhesive sheet from the plasma by the cover, plasma concentration on the frame, thermal deformation of the adhesive sheet, contamination of the object due to reattachment of the gasified adhesive component, and the like are reduced or alleviated.

  The cover disclosed in Patent Document 1 is always disposed in the plasma processing unit and is moved up and down by a lifting mechanism. Specifically, the cover is located at a raised position away from the stage when the carrier is carried in and out, and is located at a lowered position that covers the frame and the adhesive sheet during plasma processing. However, when a cover lifting device is provided in the plasma processing unit, the structure of the plasma processing unit is inevitably complicated. In addition, if there is an elevating device for the cover in the plasma processing unit, it is difficult to make the gas flow in the plasma processing unit uniform or smooth, which is disadvantageous in improving the processing performance.

  Patent Document 2 discloses a plasma processing apparatus in which a transport carrier is held by another cover type carrier and can be transported. Since the frame and the adhesive sheet (area between the object and the frame) are covered with the cover type carrier, they are shielded from the plasma. Since a cover-type carrier (a member corresponding to the cover of Patent Document 1) is attached to each transport carrier, it is not necessary to always place a cover in the plasma processing unit, and a lifting device for the cover is unnecessary. However, since a cover-type carrier is provided for each individual transport carrier, the same number of cover-type carriers as the transport carrier is required, resulting in an increase in cost.

JP 2009-94436 A JP 2006-66602 A

  It is an object of the present invention to provide a plasma processing apparatus and a plasma processing method that do not require a cover lifting mechanism for shielding from plasma without increasing the cost.

  According to a first aspect of the present invention, there is provided a transport carrier including a plasma processing unit that performs plasma processing on an object, a holding sheet that holds the object, and a frame to which the holding sheet is attached. A first storage part that is stored in a possible manner, a main body for covering the holding sheet and the frame, and a window part for exposing the object formed in the main body so as to penetrate in the thickness direction; A transporting device capable of transporting while holding the cover so that the cover is positioned on the transport carrier, and a transport device. And controlling the object so that the object is taken out of the carrier before being plasma-treated from the first storage unit, and then positioned on the removed carrier. The cover is taken out from the storage unit 2, the carrier is carried into the plasma processing unit together with the cover, and the carrier in which the object has been plasma treated is carried out from the plasma processing unit together with the cover. And a controller that stores the transport carrier in the first storage section after the cover is stored in the second storage section.

  The cover taken out from the second storage unit by the carrying device is carried into the plasma processing unit in a state of being positioned on the carrying carrier taken out from the first carrying unit. During the plasma processing on the object in the plasma processing section, the main body of the cover shields the holding sheet and the frame of the carrier from the plasma. After the plasma processing, the cover is unloaded from the plasma processing unit together with the transport carrier by the transport device, and returned to the second storage unit. Therefore, it is not necessary to always place a cover in the plasma processing unit and lift and lower it by the lifting device when the carrier is carried in and out.

  Since it is not necessary to provide an elevating device for the cover in the plasma processing unit, the configuration of the plasma processing unit is simplified. Further, since there is no lifting device, the flow of process gas in the plasma processing unit can be made uniform or smooth, and the processing performance can be improved. Furthermore, since it is not necessary to connect to the lifting device, the outer dimensions of the cover can be reduced. As a result of reducing the outer dimensions of the cover, the flow area of the process gas can be secured in the plasma processing unit, and the flow of the process gas in the plasma processing unit can be made uniform or smooth. By smoothing the flow of the process gas, the characteristics of the plasma treatment for the object can be improved.

  The cover returned to the second storage unit after the plasma processing is carried into the plasma processing unit together with the next carrier (the object is before the plasma processing). That is, since the cover is used repeatedly, it is not necessary to provide a cover for each individual carrier. Therefore, it is not necessary to prepare as many covers as the number of transport carriers, and an increase in cost can be avoided.

  The first storage unit includes a plurality of first shelves in a multi-stage arrangement in which the transport carriers are stored, and the second storage unit is arranged in a multi-stage with the first shelves, and the cover Is provided with at least one second shelf. In particular, it is preferable that the first shelf and the second shelf are provided in a single cassette. By providing the first shelf (conveyance carrier) for the transport carrier and the second shelf for the cover in the same cassette, the apparatus configuration can be simplified.

  The transport device includes a support portion on which the transport carrier and the cover can be placed simultaneously. Specifically, the support portion includes a first placement portion for placing the transport carrier and a second placement portion for placing the cover located outside and above the first portion. The mounting part is provided. Preferably, the difference in height between the first placement unit and the second placement unit is set on the transport carrier placed on the first placement unit and the second placement unit. It sets so that a clearance gap may be formed between the said covers.

  The second storage unit detachably stores a plurality of covers, and one of the covers is used to shield the holding sheet of the carrier and the plasma from the frame in the plasma processing unit. While being done, it is preferred that the other cover is cooled. For example, the plasma processing apparatus includes a transfer unit in which the transfer device is accommodated, and a gas cooling mechanism that injects and exhausts an inert gas to the transfer unit, and the control device includes a plurality of covers. While the one is in the plasma processing unit, the transport device takes the other cover out of the second storage unit and moves it to the transport unit, and the cooling mechanism causes the inert gas to the transport unit to move. After the injection and the exhaust are performed, the transport device is caused to return the other cover from the transport unit to the second storage unit. With this configuration, while one cover is in the plasma processing unit for plasma processing on the object of the transport carrier, the other cover can be cooled to suppress an increase in temperature. As a result, radiant heat from the cover to the object can be suppressed.

  According to a second aspect of the present invention, a carrier that includes a holding sheet that holds an object to be plasma-treated and a frame to which the holding sheet is attached is taken out of the first storage unit, and the holding sheet and the frame A cover including a main body for covering the main body and a window portion formed so as to penetrate the main body in the thickness direction is taken out from the second storage portion so as to be positioned on the taken-out transport carrier, and the transport The carrier is carried into the plasma processing unit together with the cover, and the body of the cover covers the holding sheet and the frame, and the object is exposed from the window portion of the cover together with the carrier. Is placed on a stage in the plasma processing unit, and plasma is generated in the plasma processing unit to plasma process the object. To provide a method. After the plasma processing of the object, the carrier is lifted from the stage of the plasma processing unit together with the cover, is unloaded from the plasma processing unit, the cover is returned to the second storage unit, and the carrier Is returned to the first storage portion.

  According to the present invention, the cover taken out from the second storage unit by the carrying device is carried into the plasma processing unit in a state of being positioned on the carrying carrier taken out from the first carrying unit. Since it is not necessary to provide an elevating device for the cover in the plasma processing unit, the configuration of the plasma processing unit is simplified. Further, since there is no lifting device, the flow of process gas in the plasma processing unit can be made uniform or smooth, and the processing performance can be improved. Furthermore, since it is not necessary to connect to the lifting device, the outer dimensions of the cover can be reduced. As a result of reducing the outer dimensions of the cover, the flow area of the process gas can be secured in the plasma processing unit, and the flow of the process gas in the plasma processing unit can be made uniform or smooth. By smoothing the flow of the process gas, the characteristics of the plasma treatment for the object can be improved.

  The cover returned to the second storage unit after the plasma processing is carried into the plasma processing unit together with the next carrier (the object is before the plasma processing). That is, since the cover is used repeatedly, it is not necessary to provide a cover for each individual carrier. Therefore, it is not necessary to prepare as many covers as the number of transport carriers, and cost increase can be avoided.

The schematic diagram of the plasma processing apparatus which concerns on 1st Embodiment of this invention. The schematic diagram of a plasma processing part. The typical perspective view of a cassette and a conveyance apparatus. Sectional drawing in the IV-IV line of FIG. The top view of the support fork of the conveying apparatus of the state holding the conveyance carrier and the cover. Sectional drawing in the VI-VI line of FIG. The perspective view for demonstrating the outline of the taking-out operation | movement from the cassette of a conveyance carrier and a cover. The perspective view for demonstrating the outline of the accommodation operation | movement to the cassette of a conveyance carrier and a cover. The schematic diagram for demonstrating operation | movement of the cassette at the time of taking out a conveyance carrier and a cover, and a conveyance apparatus. The schematic diagram for demonstrating operation | movement of the cassette and conveyance apparatus at the time of accommodation of a conveyance carrier and a cover. The typical perspective view for demonstrating the operation | movement at the time of arrangement | positioning to the stage of a conveyance carrier and a cover. The top view of the stage in the state in which the conveyance carrier and the cover were mounted. Sectional drawing in the XIII-XIII line | wire of FIG. Sectional drawing similar to FIG. 12 which shows the alternative of a cover. The flowchart which shows operation | movement of the plasma processing apparatus which concerns on 1st Embodiment. The schematic diagram for demonstrating the operation | movement at the time of taking out from the cassette of a conveyance carrier and a cover. The schematic diagram for demonstrating the operation | movement at the time of carrying in to the plasma processing part of a conveyance carrier and a cover. The schematic diagram for demonstrating the operation | movement at the time of cooling of a cover. The schematic diagram for demonstrating the operation | movement at the time of carrying out from the plasma processing part of a conveyance carrier and a cover. The schematic diagram for demonstrating the operation | movement at the time of accommodation to the cassette of a conveyance carrier and a cover. Sectional drawing similar to FIG. 6 of the cassette with which the plasma processing apparatus which concerns on 2nd Embodiment of this invention is provided. The flowchart which shows operation | movement of the plasma processing apparatus which concerns on 2nd Embodiment.

(First embodiment)
1 and 2 show a dry etching apparatus 1 which is an example of a plasma processing apparatus according to an embodiment of the present invention. The dry etching apparatus 1 includes a plasma processing unit 2 that performs dry etching on a wafer or substrate 14 that is an example of an object, and a transfer unit 3 that is provided adjacent to the plasma processing unit 2. A transport device 25 is accommodated in the transport unit 3. In addition, a load lock unit 4 is provided adjacent to the transport unit 3. The transport unit 3 communicates with the plasma processing unit 2 and the load lock unit 4. Gate valves 6 </ b> A and 6 </ b> B for opening and closing these are provided in the communication port 5 </ b> A of the transfer unit 3 and the plasma processing unit 2 and the communication port 5 </ b> B of the transfer unit 3 and the load lock unit 4. The transport unit 3 and the load lock unit 4 are connected to a nitrogen gas source 8 which is an example of an inert gas source through partition valves 7A and 7B, and connected to the vacuum exhaust unit 10 through partition valves 9A and 9B. Yes.

  A control device 11 schematically shown only in FIGS. 1 and 2 includes, in addition to the plasma processing unit 2, a transport unit 3 (particularly the transport unit 25) and a load lock unit 4 (particularly a lifter 20 of a cassette 21 described later). The entire dry etching apparatus 1 is comprehensively controlled to perform plasma processing (dry etching) on the substrate 14.

  The dry etching apparatus 1 performs plasma processing in a state where the substrate 14 as an object is held on the transport carrier 13. The carrier 13 is generally circular in plan view, and includes a holding sheet 15 that detachably holds a substrate 14 (circular in this embodiment). As the holding sheet 15, for example, an adhesive tape (so-called UV tape) that can be elastically extended and holds the substrate 14 by adhesive force, but its chemical properties change due to irradiation of ultraviolet rays to greatly reduce the adhesive force. ) Can be used. The holding sheet 15 is flexible, and can be easily bent by itself to hold a fixed shape. Therefore, in the present embodiment, an annular and thin frame 16 is attached to the outer peripheral edge of the holding sheet 15. The frame 16 is made of, for example, metal and has rigidity that can hold the shape of the holding sheet 15. As will be described in detail later, the transport carrier 13 is housed in a cassette 21 housed in the load lock unit 4 so that it can be taken in and out, and is transported in the load lock unit 4, the transport unit 3, and the plasma processing unit 2 by the transport device 25. Is done.

  The dry etching apparatus 1 covers the holding sheet 15 (the region between the substrate 14 and the frame 16, hereinafter referred to as an exposed portion of the holding sheet 15) of the transport carrier 13 and the frame 16 from above and shields them from the plasma. Two covers 17 having the same shape for exposing only 14 to the plasma are provided. The cover 17 has a generally thin annular shape, and includes a main body 17a for covering the exposed portion of the holding sheet 15 and the frame 16, and a circular window portion 17b for exposing the substrate 14 in the thickness direction at the center of the main body 17a. It is formed through. As will be described in detail later, the cover 17 is housed in a cassette 21 housed in the load lock unit 4 so as to be able to be taken in and out, and is transported together with the transport carrier 13 through the load lock unit 4, the transport unit 3, and the plasma processing unit 2. Is done. The outer dimension (outer diameter) of the cover 17 in plan view is set larger than the outer dimension (outer diameter) of the transport carrier 13 so as to cover the frame 16 of the transport carrier 13 to the outermost periphery.

  Referring to FIG. 6, the main body 17 a of the cover 17 includes a supported portion 17 c that protrudes downward from the lower surface of the outermost peripheral portion. The supported portion 17c has an annular shape with a flat bottom end. Further, an annular main escape groove 17d having a constant width is provided adjacent to the supported portion 17c on the lower surface of the main body 17a. Further, an annular auxiliary escape groove 17e having a constant width is provided at the bottom of the main escape groove 17d.

  The load lock unit 4 will be described with reference to FIGS. 3 and 4 in addition to FIGS.

  The load lock unit 4 accommodates a cassette 21 that is lifted and lowered by a lifter 20. As shown in FIG. 1, the load lock unit 4 is provided with a loading / unloading port 4a for the cassette 21 and a gate 4b for opening and closing the loading / unloading port 4a. As shown most clearly in FIG. 4, the cassette 21 comprises a plurality of shelves. The cassette 21 in the present embodiment includes eight carrier shelves (first shelves) 22 from the lowest level. One carrier carrier 13 is accommodated in each carrier shelf 22 so as to be able to be taken in and out in a horizontal posture. These carrier shelves 22 constitute a first storage portion in the present invention. The cassette 21 further includes two-stage cover shelves (second shelves) 23A and 23B arranged in multiple stages on the uppermost carrier shelf 22. A single cover 17 is accommodated in each cover shelf 23A, 23B in a horizontal posture so that it can be taken in and out. These cover shelves 23A and 23B constitute a second storage portion in the present invention.

  The cassette 21 includes a side wall 21c and a back wall 21d between the top plate 21a and the bottom plate 21b. From the side wall 21c and the back wall 21d, the carrier shelf 22 and the cover shelves 23A and 23B protrude horizontally. The amount of protrusion from the side wall 21c and the back wall 21d of the carrier shelf 22 is set so that the frame 16 of the transport carrier 13 is placed on the upper surface. The amount of protrusion of the cover shelves 23A, 23B from the side wall 21c and the back wall 21d is set so that the supported portion 17c at the outermost periphery of the cover 17 is placed on the upper surface. As shown most clearly in FIG. 8, the eight-stage carrier shelves 22 are provided at the same arrangement pitch P, and the two-stage cover shelves 23 </ b> A and 23 </ b> B are also provided at the same arrangement pitch P as the carrier shelves 22. ing. The lifter 20 can raise and lower the cassette 21 at a pitch ½ of the pitch P of the carrier shelf 22 and the cover shelves 23A and 23B. A large area opening 21e including all the carrier shelves 22 and the cover shelves 23A and 23B is provided on the side (the right side in FIG. 3) of the cassette 21 that faces the transport 3 (the transport device 25). ing. A support fork 26 of the transfer device 25 described later enters and leaves the inside of the cassette 21 through the opening 21e.

  The transport unit 3 will be described with further reference to FIGS. 3, 5, and 6 in addition to FIGS. 1 and 2.

  The transport device 25 accommodated in the transport unit 3 is a single arm type transport robot in the present embodiment. Specifically, the transport device 25 includes a single support fork (support portion) 26 that can place and support both the transport carrier 13 and the cover 17 at the same time. The support fork 26 includes a base portion 26a and a pair of finger portions 26b extending from the base portion 26a in a generally parallel manner with a space therebetween. The base 26a of the support fork 26 is connected to a two-link type horizontal movement mechanism 27 that can move in two directions in a horizontal plane, and the horizontal movement mechanism 27 is mounted on a pivot 28 that extends in the vertical direction. The pivot 28 can rotate about its own axis. Therefore, the support fork 26 can be linearly moved and swiveled in two directions within a certain horizontal plane.

  As shown in FIGS. 5 and 6, the base portion 26a and the finger portion 26b of the support fork 26 have a carrier mounting portion (first mounting portion) that is a horizontal flat surface having a substantially partial arc shape in plan view. Part) 26c. A recess 26d is provided adjacent to the inside of the carrier placement portion 26c. The bottom surface of the recess 26d is positioned below the carrier placement portion 26c. Adjacent to the outer side of the carrier placement portion 26c, a cover placement portion (second placement portion) 26e, which is a horizontal flat surface having a substantially partial arc shape and a constant width in plan view, is provided. The cover placing part 26e is located above the carrier placing part 26c.

  As shown in FIG. 6, the frame 16 of the transport carrier 13 can be placed on the carrier placement portion 26c. An interval is provided between the pair of finger portions 26b, and a recess 26d is provided inside the carrier placement portion 26c. For this reason, when the frame 16 is placed on the carrier placement portion 26 c, there is a gap between the most area of the lower surface of the holding sheet 15 of the transport carrier 13 and the upper surface of the support fork 26. In other words, the carrier 13 is substantially supported by the support fork 26 from the lower surface side only on the frame 16.

  As shown in FIG. 6, the cover 17 can be placed on the cover placement portion 26e. The lower end surface of the supported portion 17c of the cover 17 is placed on the cover placement portion 26e. The cover 17 placed on the cover placing portion 26e is positioned above the transport carrier 13 placed on the carrier placing portion 26c with a space on the entire lower surface. In particular, the frame 16 of the transport carrier 13 placed on the carrier placement portion 26c is not in contact with the lower surface of the cover 17 because the upper end faces the main escape groove 17d. The difference between the height positions of the carrier mounting portion 26c and the cover mounting portion 26e of the support fork 26 depends on the protruding amount of the supported portion 17c and the depth of the main escape groove 17d. It is set so that the entire lower surface side of the cover 17 is not in contact with the transport carrier 13 when the 17 is placed simultaneously.

  The support fork 26 includes inclined surfaces 26f and 26g on the outer side of the carrier mounting portion 26c and the outer side of the cover mounting portion 26e. These inclined surfaces 26f and 26g are placed in a correct posture with respect to the carrier placing portion 26c and the cover placing portion 26e when the carrier 13 and the cover 17 are placed on the support fork 26 described later. And a function of guiding the carrier 13 and the cover 17.

  By moving the support fork 26 of the transport device 25 with respect to the cassette 21 and moving the cassette 21 up and down by the lifter 20, the transport carrier 13 is put in and out of the individual carrier shelf 22, and the cover 17 of the individual cover shelf 23 A, 23 B is moved. Putting in and out is performed. When the transport carrier 13 and the cover 17 are taken out from the cassette 21, the transport carrier 13 is first taken out from the cassette 21 by the support fork 26 (see FIG. 7), and then the support fork 26 of the transport device 25 (the transport carrier 13 is removed). The cover 17 is taken out from the cassette 21 (see FIG. 8). On the contrary, when the transport carrier 13 and the cover 17 are stored in the cassette 21, first, the cover 17 is stored in the cassette 21 from the support fork 26 (both the transport carrier 13 and the cover 17 are placed). Subsequently, the transport carrier 13 is stored in the cassette 21 from the support fork 26 (FIG. 8).

  With reference to FIG. 9, the operation of taking out the carrier 13 and the cover 17 from the cassette 21 will be described.

  First, the support fork 26 enters the lower side of the carrier 13 to be taken out (step 1). Specifically, the support fork 26 enters an intermediate height position between the carrier carrier 13 to be taken out and the carrier carrier 13 one level below. Next, as shown in step 2, the cassette 21 is lowered by ½ of the pitch P (hereinafter referred to as ½P), so that the frame of the transport carrier 13 is placed on the carrier mounting portion 26 c of the support fork 26. 16 is placed. Subsequently, the cassette 21 is further lowered by 1 / 2P, so that the transport carrier 13 is lifted by the support fork 26 and is lifted from the carrier shelf 22 of the cassette 21 (step 3). That is, the transport carrier 13 is transferred from the carrier shelf 22 of the cassette 21 to the support fork 26. At this time, the conveyance carrier 13 is reliably placed on the carrier placement portion 26c of the support fork 26 in a horizontal posture by being guided by the inclined surface 26f shown in FIG. The support fork 26 on which the transport carrier 13 is placed temporarily leaves the cassette 21 (step 4).

  Next, after the cassette 21 is lowered by a predetermined amount, the support fork 26 on which the transport carrier 13 is placed again enters the cassette 21 (step 5). At the time of this re-entry, the support fork 26 enters a lower height position by 1 / 2P of one of the two covers 17 (in this example, the cover 17 housed in the upper cover shelf 23A). Next, when the cassette 21 is lowered by 1 / 2P, the cover 17 is placed on the cover placement portion 26e of the support fork 26 (step 6). Subsequently, when the cassette 21 is further lowered by 1 / 2P, the cover 17 lifted by the support fork 26 is lifted from the cover shelf 23A (step 7). That is, the cover 17 is delivered from the cover shelf 23A to the support fork 26. At this time, the cover 17 is surely placed on the cover placement portion 26e of the support fork 26 in a horizontal posture by being guided by the inclined surface 26g shown in FIG. Finally, the support fork 26 supporting both the transport carrier 13 and the cover 17 is withdrawn from the cassette 21 (step 8).

  With reference to FIG. 10, the operation | movement which accommodates the conveyance carrier 13 and the cover 17 in the cassette 21 is demonstrated.

  First, on the upper side of the cover shelves 23A and 23B where the cover 17 is not placed (in this example, the cover shelf 23A), the carrier carrier 13, the support fork 26 on which the cover 17 and the cover 17 are placed is provided. Enter (step 1). Specifically, the support fork 26 enters upward by 1 / 2P of the cover shelf 23A. Next, as shown in step 2, when the cassette 21 is raised by 1 / 2P, the support fork 26 is lowered relative to the cover shelf 23A, and the supported portion 17c of the cover 17 is moved to the cover shelf 23A. It is placed on (step 2). Subsequently, when the cassette 21 is further raised by 1 / 2P, the cover 17 is separated from the support fork 26 (step 3). That is, the cover 17 is delivered from the support fork 26 to the cover shelf 23A. The support fork 26 that has transferred the cover 17 to the cover shelf 23A once leaves the cassette 21 (step 4).

  Next, after the cassette 21 is raised by a predetermined amount, the support fork 26 on which the transport carrier 13 is placed again enters the cassette 21 (step 5). At the time of this re-entry, the support fork 26 enters a height position that is 1 / 2P above any one of the carrier shelves 22 in which the transport carrier 13 is not stored (in this example, the uppermost carrier shelf 22). Next, as shown in step 6, the cassette 21 is raised by 1 / 2P, so that the support fork 26 is relatively lowered toward the uppermost carrier shelf 22, and the transport carrier 13 is moved to the carrier shelf 22. Placed on. Subsequently, when the cassette 21 is further raised by 1 / 2P, the transport carrier 13 is separated from the support fork 26 (step 7). That is, the transport carrier 13 is transferred from the support fork 26 to the uppermost carrier shelf 22. Finally, the support fork 26 is withdrawn from the cassette 21 (step 8).

  The plasma processing unit 2 will be described with reference to FIGS. 2 and 11 to 13. The plasma processing apparatus of this embodiment is a parallel plate electrode type plasma processing apparatus having an upper electrode and a lower electrode. The plasma processing unit 2 includes an upper electrode 31 on the top wall side. The upper electrode 31 is grounded. The upper electrode 31 is provided with a process gas supply port 33. The process gas supplied from the process gas supply unit 34 is ejected from the process gas supply port 33 into the plasma processing unit 2. On the other hand, in the present embodiment, a circular stage 35 is provided on the bottom wall side of the plasma processing unit 2 in a plan view. The stage 35 includes a lower electrode 36 and a table portion 37 provided on the outer periphery around the lower electrode 36. The lower electrode 36 is electrically connected to the high frequency power supply 32. The plasma processing unit 2 cools the lower electrode 36 by circulating a temperature-controlled refrigerant and a substrate holding mechanism 38 (for example, an electrostatic chuck) that detachably holds the substrate 14 on the upper end surface of the lower electrode 36. And a cooling mechanism 39. A vacuum exhaust unit 41 for suction exhaust is connected to the exhaust port 40 provided at the lower part of the plasma processing unit 2. A plurality of push-up pins (push-up members) 42 that can be moved up and down are provided so as to penetrate the stage 35. The push-up pin 42 is driven up and down by the up-and-down drive unit 43 and is movable between a lowered position where the upper end is housed in the stage 35 and a raised position where the upper end is located above the upper surface of the stage 35.

  The carrier 13 and the cover 17 taken out from the cassette 21 by the carrier device 25 are carried into the plasma processing unit 2 from the load lock unit 4 through the carrier unit 3 and placed on the stage 35. Referring to FIG. 11, when placing the transport carrier 13 and the cover 17 on the stage 35, first, the support fork 26 (the transport carrier 13 and the cover 17 are placed) of the transport device 25 is placed on the stage 35. Enter above. Next, the push-up pin 42 rises and pushes up the lower surface of the frame 16 of the transport carrier 13. As a result, the transport carrier 13 is lifted from the carrier placement portion 26 c of the support fork 26. That is, the transport carrier 13 is transferred from the support fork 26 to the push-up pin 42. The upper part of the cover 17 pushed up by the push-up pin 42 comes into contact with the bottom part of the main escape groove 17 d provided in the frame 16 of the transport carrier 13. Therefore, the cover 17 is placed on the frame 16 as the push-up pin 42 is raised, and is transferred from the support fork 26 to the push-up pin 42 together with the transport carrier 13. After the transport carrier 13 and the cover 17 are transferred to the push-up pin 42, the support fork 26 is retracted from above the stage 35. After the support fork 26 is retracted, the push-up pin 42 is in the lowered position, and the transport carrier 13 and the cover 17 are placed on the stage 35. After the plasma processing on the substrate 14, the transport carrier 13 and the cover 17 are transferred from the stage 35 to the support fork 26 by an operation reverse to the operation shown in FIG. 11.

  12 and 13 show the transport carrier 13 and the cover 17 placed on the stage 35. FIG. The exposed portion of the holding sheet 15 of the transport carrier 13 and the frame 16 placed on the stage 35 are covered with the main body 17a of the cover 17 from above. The substrate 14 is exposed from the cover 17 through the window portion 17b. The substrate 14 on the holding sheet 15 is disposed on the lower electrode 36, and the frame 16 is disposed on the table unit 37. The cover 17 has a lower end of the supported portion 17c in contact with the upper surface of the table portion 37, and a bottom portion of the main escape groove 17d is in contact with an upper portion of the frame 16, so that the cover 17 is covered on the stage 35 from above. Retained.

  The substrate 14 during the plasma processing is held in close contact with the upper surface of the lower electrode 36 via the holding sheet 15 by the substrate holding mechanism 38. While introducing the process gas from the process gas supply unit 34 through the process gas supply port 33, the process gas supply unit 34 exhausts the gas by the vacuum exhaust unit 41, and the inside of the plasma processing unit 2 is maintained at a predetermined pressure. Thereafter, high frequency power is supplied from the high frequency power supply 32 to the lower electrode 36 to generate plasma in the plasma processing unit 2 and irradiate the substrate 14 exposed from the window 17 b of the cover 17. Further, the lower electrode 36 is cooled by the cooling mechanism 39, and the stage 35 is also cooled by heat conduction with the lower electrode 36. The exposed portion of the frame 16 and the holding sheet 15 of the transport carrier 13 is covered with the main body 17a of the cover 17 so that it is shielded from plasma.

  The cover 17 during the plasma treatment is cooled by heat conduction with the stage 35 because the supported portion 17 c is in contact with the stage 35 cooled by the cooling mechanism 39. Further, the cover 17 and the frame 16 of the carrier 13 are in contact with each other only at the bottom of a main escape groove 17 d provided in the main body 17 a of the cover 17. In addition, since the auxiliary escape groove 17e is provided in the main escape groove 17d, the contact area between the frame 16 and the cover 17 is minimized. As a result, even if the cover 17 is heated to a high temperature during the plasma processing, the heat transfer from the cover 17 to the frame 16 is limited, and the temperature rise of the frame 16 is suppressed to a minimum. The sheet 15 is not damaged, and thus troubles caused by the damage of the holding sheet 15 can be avoided.

  FIG. 14 shows an alternative to the cover 17. In this alternative, a projection 17f is provided at the bottom of the main escape groove 17d of the main body 17a instead of the auxiliary escape groove 17e of FIG. The cover 17 and the frame 16 of the transport carrier 13 are in contact with each other only at the lower end of the projection 17f, and thereby the contact area between the frame 16 and the cover 17 is minimized.

  Next, a dry etching method executed by the dry etching apparatus 1 of the present embodiment will be described with reference to the flowchart shown in FIG.

  After the cassette 21 containing the transport carrier 13 (the substrate 14 is not plasma-treated) and the cover 17 is loaded into the load lock unit 4 from the loading / unloading port 4a, the load lock unit 4 is first evacuated. Specifically, the gate valve 9B is opened, and the inside of the load lock unit 4 is exhausted by the vacuum exhaust unit 10 (step S1). Next, the transport carrier 13 is removed from the cassette 21 by the support fork 26 of the transport device 11 (step S2), and then the cover 17 is removed from the cassette 21 (step S3).

  The operation of steps S2 and S3 in FIG. 15 will be described with reference to FIG. The support shaft 26 is directed to the load lock unit 4 in the transport unit 3 by the turning shaft 28, and the gate valve 6B of the communication port 5B is opened (state 1). Next, the support fork 26 advances straight by the horizontal movement mechanism 27, enters the load lock portion 4 through the communication port 5B, and enters the cassette 21. Then, by the operation described with reference to FIG. 9, one transport carrier 13 is placed on the carrier placement portion 26c (see FIG. 6) of the support fork 26 (state 2). The support fork 26 on which the transport carrier 13 is placed moves straight by the horizontal movement mechanism 27, exits from the cassette 21, and returns to the transport unit 3 through the communication port 5B (state 3). Next, the support fork 26 on which the transport carrier 13 is placed moves straight by the horizontal movement mechanism 27 and enters the cassette 21, and the cover placement portion 26e of the support fork 26 is obtained by the operation described with reference to FIG. One cover 17 is placed on the (state 4). The support fork 26 on which the transport carrier 13 and the cover 17 are placed moves straight by the horizontal movement mechanism 27 and returns to the transport unit 3 (state 5). Next, the support fork 26 is directed to the plasma processing unit 2 by the turning shaft 28, and the communication port 5B of the transfer unit 3 and the load lock unit 4 is closed by the gate valve 6B (state 6).

  In step S <b> 4 of FIG. 15, the transport carrier 13 and the cover 17 placed on the support fork 26 are carried into the plasma processing unit 2 and placed on the stage 35. This operation will be described with reference to FIG. The support fork 26 on which the transport carrier 13 and the cover 17 are placed faces the plasma processing unit 2 (state 1). The gate valve 6A is opened, and the support fork 26 goes straight by the horizontal movement mechanism 27 and enters the plasma processing unit 2 through the communication port 5A (state 2). Further, the transport carrier 13 and the cover 17 are transferred from the support fork 26 to the stage 35 by the operation described with reference to FIG. After the transport carrier 13 and the cover 17 are placed on the stage 13, the support fork 26 advances straight by the horizontal movement mechanism 27 and returns to the transport unit 3 through the communication port 5A (state 3). Thereafter, the gate valve 6A is closed.

  After the placement of the carrier 13 and the cover 17 on the stage 35 (Step S4) is completed, the plasma processing is performed on the substrate 14 in the plasma processing unit 2 (Step S5).

  In the present embodiment, between the start and end of the plasma processing (step S5), the two covers 17 that are not used for shielding the plasma (the plasma processing unit 2 out of the two covers 17). Rather than those stored in the cassette 21 (steps S9 to S13).

  First, the cover 17 is removed from the cassette 21 (step S9). Specifically, as shown in FIG. 18, the fork 26 is directed to the load lock portion 4 by the pivot shaft 28, and the gate valve 6B is opened (state 1). Subsequently, the support fork 26 advances straight by the horizontal movement mechanism 26, enters the load lock unit 4 through the communication port 5B, enters the cassette 21, and the cover 17 covers the cover placement unit 26e of the support fork 26 (see FIG. 6). (State 2). The support fork 26 on which the cover 17 is placed moves straight by the horizontal movement mechanism 26 and returns to the transport unit 3 (state 3). Further, the gate valve 6B between the transport unit 3 and the load lock unit 4 is closed (state 4).

  After moving to the transport unit 3 on which the cover 17 is placed and the gate valve 6B is closed, the interior of the transport unit 3 is evacuated (step S9). Specifically, the gate valve 9A is opened, and the inside of the transport unit 3 is exhausted by the vacuum exhaust unit 10 (step S10). Next, nitrogen gas is injected into the transport unit 3 (step S11). Specifically, the partition valve 7 </ b> A is opened, and nitrogen gas is injected into the transport unit 3 from the nitrogen gas source 8. Next, nitrogen gas is exhausted from the transport unit 3 (step S12). Specifically, the partition valve 9 </ b> A is opened, and the nitrogen gas in the transport unit 3 is exhausted by the vacuum exhaust unit 10. The cover 17 placed on the support fork 26 in the transport unit 3 is cooled by injecting and exhausting nitrogen gas. After exhausting the nitrogen gas, the cover 17 is stored in the cassette 21. Specifically, after the gate valve 6B is opened, the horizontal fork mechanism 26 causes the support fork 26 to enter the load lock portion 4 via the communication port 5B and enter the cassette 21 (state 5 in FIG. 18). Further, the cover 17 is transferred from the support fork 26 to one of the cover shelf portions 23A and 23B of the cassette 21 by the operation described with reference to FIG. After the cover 17 is stored in the cassette 21, the support fork 26 advances straight by the horizontal movement mechanism 27 and returns to the transport unit 3 (state 6 in FIG. 18).

  After the plasma processing (step S5) on the substrate 14 is completed, the transport carrier 13 and the cover 17 are unloaded from the plasma processing unit 2 by the support fork 26 of the transport device 11 (step S6). Specifically, the gate valve 6A is opened (state 1 in FIG. 19), and then the support fork 26 advances straight by the horizontal movement mechanism 27 and enters the plasma processing unit 2 through the communication port 5A (in FIG. 19). State 2). Further, the transport carrier 13 and the cover 17 are transferred from the stage 35 to the support fork 26 by an operation reverse to the operation shown in FIG. The support fork 26 on which the transport carrier 13 and the cover 17 are placed moves straight by the horizontal movement mechanism 27 and moves from the plasma processing unit 2 to the transport unit 3 through the communication port 5A (state 3 in FIG. 19). Thereafter, the gate valve 6A is closed, and the support fork 26 is directed to the load lock portion 4 by the pivot shaft 28 (state 4 in FIG. 19).

  Next, the cover 13 placed on the support fork 26 is housed in the cassette 21 (state 7), and the transport carrier 13 (the substrate 14 has been plasma-treated) placed on the support fork 26 is also loaded into the cassette 21. Stored.

  The operations in steps S7 and S8 in FIG. 15 will be described with reference to FIG. The support shaft 26 is directed to the load lock unit 4 in the transport unit 3 by the pivot shaft 28, and the gate valve 6B is opened (state 1). Next, the support fork 26 advances straight by the horizontal movement mechanism 27, enters the load lock portion 4 through the communication port 5B, and enters the cassette 21. Then, by the operation described with reference to FIG. 10, one of the cover shelves 23 </ b> A and 23 </ b> B of the cassette 21 (the cover 17 is not accommodated) from the cover mounting portion 26 e (see FIG. 6) of the support fork 26. ), The cover 17 is delivered (state 2). Next, the support fork 26 on which only the transport carrier 13 is placed goes straight by the horizontal movement mechanism 27 and returns to the transport unit 3 through the communication port 5B (state 3). Next, the support fork 27 on which the transport carrier 13 is placed moves straight by the horizontal movement mechanism 27 and enters the cassette 21. Then, by the operation described with reference to FIG. 10, the transport carrier 13 is moved from the carrier mounting portion 26 c of the support fork 26 to any one of the carrier shelves 22 of the cassette 21 (the transport carrier 13 is not stored). Passed (state 4). Next, the support fork 26 advances straight by the horizontal movement mechanism 27 and returns to the transport unit 3 (state 5).

  The operations in steps S2 to S13 in FIG. 15 are repeated until the substrate 14 has been subjected to plasma processing for all the transport carriers 13 accommodated in the cassette 21.

  The dry etching apparatus 1 of this embodiment has the following characteristics.

  The cover 17 is taken out from the cassette 21 together with the carrier carrier 14 and carried into the plasma processing unit 2, and is returned to the cassette 21 together with the carrier carrier 14 after the plasma treatment of the substrate 14 is completed. That is, the cover 17 that shields the holding sheet 15 and the frame 16 of the transport carrier 14 from the plasma during plasma processing on the substrate 14 is not always disposed in the plasma processing unit 2, but the transport carrier 14 is mounted on the stage 35. There is no need to raise and lower during placement and removal. Therefore, since it is not necessary to provide an elevating device for the cover 17 in the plasma processing unit 2, the configuration of the plasma processing unit 2 is simplified. Further, since there is no lifting device, the flow of process gas in the plasma processing unit 2 can be made uniform or smooth, and the processing performance can be improved. Furthermore, since it is not necessary to connect to the lifting device, the outer dimensions of the cover 17 can be reduced. As a result of reducing the outer dimensions of the cover 17, the flow area of the process gas can be secured in the plasma processing unit 2, and the flow of the process gas in the plasma processing unit 17 can be made uniform or smooth. By smoothing the flow of the process gas, the characteristics of the plasma treatment for the object can be improved.

  The cover 17 returned to the cassette 21 after the plasma processing is then carried into the plasma processing unit 2 together with another carrier 13 (the substrate 14 is before the plasma processing). That is, since the cover 17 is repeatedly used, it is not necessary to provide a cover for each individual carrier 13. For this reason, it is not necessary to prepare as many covers as the number of the transport carrier 13, and an increase in cost can be avoided.

  The apparatus configuration is simplified in that the cover 17 is housed in a cassette 21 that is shared with the transport carrier 13. That is, a configuration in which the cover 17 is stored in a cassette separate from the transport carrier 13 so as to be able to be taken in and out is possible. However, compared to such a configuration, both the transport carrier 13 and the cover 17 are included in a single cassette 21. In this embodiment, the apparatus configuration is simple.

  While one cover 17 is used to shield the holding sheet 15 and frame 16 of the carrier carrier 13 from plasma during plasma processing of the substrate 14, as shown in steps S9 to S13 of FIG. 17 is cooled. That is, the two covers 17 are cooled alternately. Since the temperature rise of the cover 17 can be suppressed by this cooling, the radiation heat from the cover 17 to the substrate 14 can be suppressed when the holding sheet 15 and the frame 16 of the transport carrier 13 are shielded from plasma during the plasma processing of the substrate 14. Further, during the plasma processing of the substrate 14, the cover 17 is cooled by heat conduction with the stage 35, and the temperature rise of the cover 17 is also suppressed by this cooling.

(Second Embodiment)
FIG. 21 shows a cassette 21 of a dry etching apparatus according to the second embodiment of the present invention. The configuration of the dry etching apparatus excluding the cassette 21 (see, for example, FIGS. 1 and 2) is the same as that in the first embodiment. The cassette 21 in this embodiment is different from the first embodiment in that the cover shelf 23 in which the cover 17 is housed in a horizontal posture so that it can be inserted and removed is only one stage. In other words, while there are two covers 17 in the first embodiment, there is only one cover 17 in the present embodiment. FIG. 22 shows the operation of the dry etching apparatus of the second embodiment. Steps S1 to S8 in FIG. 22 are the same as steps S1 to S8 in FIG. 15 illustrating the operation of the first embodiment. Since there is only one cover 17, the operation of steps S9 to S13 in FIG. 15, that is, the operation of cooling the cover 17 that is not used for shielding the plasma is not performed during the plasma processing on the substrate 14.

  Other configurations and operations of the second embodiment are the same as those of the first embodiment.

  The present invention is not limited to the embodiment. For example, in this embodiment, a parallel plate electrode type plasma processing apparatus is used, but it goes without saying that it may be an ICP system or another type of plasma processing apparatus. Further, the cover 17 may be accommodated in a separate accommodating portion instead of the cassette 21 that is the same as the transport carrier 13. A storage portion for such a cover-dedicated storage portion may be provided separately from the load lock portion 4.

DESCRIPTION OF SYMBOLS 1 Dry etching processing apparatus 2 Plasma processing part 3 Transfer part 4 Load lock part 4a Loading / unloading port 4b Gate 5A, 5B Communication port 6A, 6B Gate valve 7A, 7B, 9A, 9B Partition valve 8 Nitrogen gas source 10 Vacuum exhaust part 11 Control Device 13 Transport carrier 14 Substrate 15 Holding sheet 16 Frame 17 Cover 17a Main body 17b Window portion 17c Supported portion 17d Main escape groove 17e Auxiliary escape groove 17f Projection 20 Lifter 21 Cassette 21a Top plate 21b Bottom plate 21c Side wall 21d Back wall 21e Opening portion 22e Carrier shelf 23A, 23B Cover shelf 25 Conveying device 26 Support fork 26a Base 26b Finger portion 26c Carrier placement portion 26d Recess 26e Cover placement portion 26f, 26g Inclined surface 27 Horizontal movement mechanism 28 Swivel shaft 31 Upper electrode 2 high-frequency power source 33 a process gas supply port 34 process gas supply portion 35 stage 36 lower electrode 37 table portion 38 substrate holding mechanism 39 cooling mechanism 40 exhaust port 41 vacuum exhaust unit 42 push-up pins 43 lift drive unit

Claims (10)

A plasma processing unit for performing plasma processing on an object;
A first storage unit that stores a transport carrier including a holding sheet that holds the object and a frame to which the holding sheet is attached;
A cover that includes a main body for covering the holding sheet and the frame, and a window that is formed so as to penetrate the main body in the thickness direction and that exposes the object. 2 storage units,
A transport device capable of transporting the transport carrier and the cover while holding the transport carrier and the cover so that the cover is positioned;
After the transport device is controlled to take out the transport carrier in which the object is not plasma-treated from the first storage unit, the second storage is positioned so as to be positioned on the transported carrier. The cover is taken out from the part, the carrier is carried into the plasma processing unit together with the cover, and the carrier, which has been subjected to the plasma treatment of the object, is carried out from the plasma processing unit together with the cover, A plasma processing apparatus comprising: a control device configured to store the transport carrier in the first storage unit after storing the cover in the second storage unit. Each of the first storage units includes a plurality of first shelves arranged in multiple stages in which the conveyance carriers are stored,
2. The plasma processing apparatus according to claim 1, wherein the second storage unit includes at least one second shelf that is arranged in multiple stages together with the first shelf and in which the cover is stored.   The plasma processing apparatus according to claim 2, wherein the first shelf and the second shelf are provided in a single cassette.   The said transfer apparatus is a plasma processing apparatus of any one of Claims 1-3 provided with the support part which can mount the said conveyance carrier and the said cover simultaneously.   The support portion includes a first placement portion for placing the transport carrier, and a second placement portion for placing the cover located outside and above the first portion. The plasma processing apparatus according to claim 4, comprising:   The difference in height between the first placement portion and the second placement portion is placed on the transport carrier placed on the first placement portion and the second placement portion. The plasma processing apparatus according to claim 5, wherein a gap is formed between the cover and the cover. The second storage unit stores a plurality of the covers in a removable manner,
The other cover is cooled while one of the plurality of covers is used to shield the holding sheet of the transport carrier and the frame from plasma in the plasma processing unit. The plasma processing apparatus according to 1. A transport unit in which the transport device is stored;
A gas cooling mechanism for injecting and exhausting an inert gas to the transfer unit,
The control device causes the transfer device to take out the other cover from the second storage unit and move it to the transfer unit while one of the plurality of covers is in the plasma processing unit, The said cooling mechanism is made to perform injection | pouring and exhaust_gas | exhaustion of the said inert gas with respect to the said conveyance part, The other said cover is returned from the said conveyance part to the said 2nd accommodating part by the said conveying apparatus. Plasma processing equipment. Taking out a transport carrier comprising a holding sheet holding a plasma processing object and a frame to which the holding sheet is attached from the first storage unit,
A cover provided with a main body for covering the holding sheet and the frame, and a window formed in the main body so as to penetrate in the thickness direction, so as to be positioned on the taken-out transport carrier. Remove from the storage,
The carrier is carried into the plasma processing unit together with the cover,
The main body of the cover covers the holding sheet and the frame, and the carrier is placed on a stage in the plasma processing unit together with the cover so that the object is exposed from the window portion of the cover,
A plasma processing method of generating plasma in the plasma processing unit to plasma process the object. After the plasma processing of the object, the carrier is lifted from the stage of the plasma processing unit together with the cover, and is unloaded from the plasma processing unit,
Return the cover to the second storage part,
The plasma processing method according to claim 9, wherein the transport carrier is returned to the first storage unit.

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