JP4833143B2 - Substrate processing equipment - Google Patents

Description

  The present invention relates to a substrate processing apparatus, and more particularly to a substrate processing apparatus that performs predetermined processing on a substrate to be processed such as a silicon wafer using plasma.

  A conventional substrate processing apparatus will be described with reference to FIG. Here, a vertical processing furnace that performs plasma processing of a plurality of substrates to be processed using a batch type plasma process will be described as an example.

  The vertical processing furnace is provided with a processing chamber 201 having an opening 220, a gas introduction port 320 for supplying gas into the processing chamber 201, an exhaust pipe 317 and a vacuum pump 319 for exhausting the processing chamber 201. The processing chamber 201 is configured to exhaust while supplying gas.

  A boat 217 as a substrate holder is inserted into the processing chamber 201 from the opening 220 of the processing chamber 201, and the boat 217 is configured to hold a plurality of wafers 200 in the processing chamber 201. Yes.

  In the boat 217, plate-like first susceptor electrodes 305 and second susceptor electrodes 306 on which the wafers 200 are placed are alternately stacked, and the first and second susceptor electrodes 305 and 306 generate plasma between the electrodes. It is configured to be able to. The boat 217 is placed on a cap receiver 309 as a rotating plate. A rotating shaft 366 that is rotationally driven by a motor 367 is connected to the cap receiver 309, and the rotating shaft 366 is configured to be able to rotatably support the boat 217 in the processing chamber 201.

  The rotating shaft 366 is pivotally supported via a magnetic seal 369 on a seal cap 219 serving as a lid that closes the opening 220 of the processing chamber 201. The seal cap 219 is configured to hermetically close the processing chamber 201 when the boat 217 is inserted into the processing chamber 201 and to rotatably support the rotation shaft 366.

  Terminal receivers 351 and 352 that are electrically insulated from the cap receiver 309 are provided on the lower side of the cap receiver 309 described above. The terminal receivers 351 and 352 are connected to the first through radio frequency (RF) feeders 353 and 354. The susceptor electrode 305 and the second susceptor electrode 306 are electrically connected.

  A movable plate 364 fitted to the guide shafts 365 and 365 is disposed below the seal cap 219. The movable plate 364 is supported by the guide shafts 365 and 365 so as to be movable up and down with respect to the seal cap 219. It is comprised so that. A cylinder 363 is provided between the seal cap 219 and the movable plate 364, and the cylinder 363 is configured to move the movable plate 364 up and down.

  The movable plate 364 is provided with first and second RF introduction terminals 361 and 362 penetrating the seal cap 219, and the first and second RF introduction terminals 361 and 362 inside the processing chamber 201 are movable by the cylinder 363. As the plate 364 moves up and down, it is configured so as to protrude from and emerge from the seal cap 219 and come into contact with or non-contact with the terminal receivers 351 and 352.

Between the seal cap 219 and the movable plate 364, first and second RF introduction terminals 361,
Flanged bellows 355 and 355 and insulating seals 368 and 368 are provided so as to surround 362. The flanged bellows 355 and 355 and the insulating seals 368 and 368 are connected to the first and second RF introduction terminals 361 and 362, respectively. It is configured such that the vertical movement can be performed in an airtight manner while maintaining electrical insulation between the seal cap 219 and the movable plate 364.

  An oscillator 315 is connected to the first and second RF introduction terminals 361 and 362 on the outside of the processing chamber 201 via a matching unit 316. The oscillator 315 includes first and second RF introduction terminals 361 and 362, terminal receptions. RF power can be applied to the first and second susceptor electrodes 305 and 306 in the processing chamber 201 via 351 and 352 and RF feeders 353 and 354, respectively.

  In such a configuration, when RF power is applied to the first and second susceptor electrodes 305 and 306 to generate plasma, the first and second RF are operated by the operation of the cylinder 363 with the boat 217 stopped rotating. The introduction terminals 361 and 362 are brought into contact with terminal receivers 351 and 352 provided on the lower surface of the cap receiver 309 of the boat 217 so that RF power can be supplied to the susceptor electrodes 305 and 306. After making RF power energizable to the susceptor electrodes 305 and 306, AC power output from the oscillator 315 is supplied between the susceptor electrodes 305 and 306 via the matching unit 316. The RF power is applied to the susceptor electrodes 305 and 306 via the terminal receivers 351 and 352, and plasma is generated between the susceptor electrodes 305 and 306. The wafer 200 is processed by this plasma generated between the susceptor electrodes 305 and 306.

  When plasma is not generated, the wafer 200 is processed with the entire boat 217 rotated. By rotating the boat 217, the gas flow in the processing chamber 201 becomes uniform, and the processing uniformity of the wafer 200 is improved.

  However, in the above-described prior art, since the rotation of the substrate holder is stopped when plasma is generated, there is a problem that uniformity of plasma processing of the substrate to be processed is deteriorated and in-plane uniformity is lowered.

  An object of the present invention is to provide a substrate processing apparatus capable of solving the above-described problems of the prior art and improving the in-plane uniformity of plasma processing of a substrate to be processed.

  According to the first aspect of the present invention, a processing chamber having an opening and forming a processing chamber therein, a substrate holder inserted into the processing chamber from the opening and holding the substrate to be processed, A lid that supports the substrate holder and hermetically closes the opening, a gas supply unit that supplies gas into the process chamber, an exhaust unit that exhausts the process chamber, and a substrate holder are stacked. At least one pair of electrodes for generating plasma, the first electrode and the second electrode on which the substrate to be processed is disposed between the electrodes, and the substrate holder in the processing chamber through the lid A rotating shaft for rotatably supporting, and a first power supply line that is introduced into the processing chamber through the rotating shaft and electrically connected to the first electrode and the second electrode, respectively. And the second power supply line and the rotating shaft A first rotating capacitor and a second rotating capacitor connected to the first power supply line and the second power supply line led out of the processing chamber, respectively, and the first rotating capacitor and the second rotating capacitor. And a high-frequency power supply means for separately supplying high-frequency power having different phases to the first electrode and the second electrode.

According to the second aspect of the present invention, a processing container having an opening and forming a processing chamber therein, a gas supply means for supplying a gas into the processing chamber, an exhaust means for exhausting the processing chamber, A substrate holder inserted into the processing chamber from the opening to hold the substrate to be processed, and at least one pair of plasma generating electrodes stacked on the substrate holder, the substrate to be processed being interposed between the electrodes The first and second electrodes are arranged, a cylindrical rotating shaft for rotatably supporting the substrate holder in the processing chamber, and the cylindrical rotating shaft is rotatably supported by the shaft. A lid that closes the opening; a conductive first rotating shaft that is inserted through the center of the cylindrical rotating shaft and is electrically connected to the first electrode inside the processing chamber; The second rotating shaft is inserted into the cylindrical rotating shaft so as to concentrically surround the rotating shaft. Conductive and hollow second rotating shaft electrically connected to the pole, insulating between the first rotating shaft and the second rotating shaft, and between the second rotating shaft and the cylindrical rotating shaft And a high-frequency power supply means for separately supplying high-frequency power having different phases between the first electrode and the second electrode via the first rotating shaft and the second rotating shaft. An apparatus is provided.

  According to the present invention, the in-plane uniformity of the plasma processing of the substrate to be processed can be improved.

Next, a preferred embodiment of the present invention will be described.
In a preferred embodiment of the present invention, the first and second susceptor electrodes on which a wafer is placed are loaded on a boat, and a rotating shaft connected to the boat is rotated so that the processing gas flows uniformly with respect to the wafer. I made it.
In supplying power to the first and second susceptor electrodes, the wafer is rotated by separately supplying high-frequency power of different phases to the first and second susceptor electrodes via the first and second rotating capacitors. While being able to process with high density plasma.
Further, the rotating shaft connected to the boat is a cylindrical rotating shaft, and the first and second rotating shafts that are electrically insulated from each other are passed through the cylindrical rotating shaft. By separately supplying high-frequency power having different phases between the first and second susceptor electrodes via the shaft, the wafer can be processed with high-density plasma while rotating.

  In the best mode for carrying out the present invention, as an example, the substrate processing apparatus is configured as a semiconductor manufacturing apparatus that performs processing steps in a method of manufacturing a semiconductor device (IC). In the following description, a case where a vertical apparatus (hereinafter simply referred to as a processing apparatus) that performs oxidation, etching, diffusion processing, CVD processing, or the like is applied to the substrate as the substrate processing apparatus will be described. FIG. 2 is shown as a perspective view of a processing apparatus applied to the present invention. FIG. 3 is a side perspective view of the processing apparatus shown in FIG.

  As shown in FIGS. 2 and 3, a hoop (substrate container; hereinafter referred to as a pod) 110 is used as a wafer carrier containing a wafer (substrate to be processed) 200 made of silicon or the like. The processing apparatus 100 includes a housing 111. A front maintenance port 103 as an opening provided for maintenance is opened at the front front portion of the front wall 111a of the casing 111, and front maintenance doors 104 and 104 for opening and closing the front maintenance port 103 are respectively built. It is attached.

  A pod loading / unloading port (substrate container loading / unloading port) 112 is opened on the front wall 111a of the casing 111 so as to communicate between the inside and the outside of the casing 111. The pod loading / unloading port 112 has a front shutter (substrate container loading / unloading port). The loading / unloading opening / closing mechanism 113 is opened and closed.

A load port (substrate container delivery table) 114 is installed in front of the front side of the pod loading / unloading port 112, and the load port 114 is configured so that the pod 110 is placed and aligned. The pod 110 is carried onto the load port 114 by an in-process carrying device (not shown), and is also carried out from the load port 114.

  A rotary pod shelf (substrate container mounting shelf) 105 is installed at an upper portion of the casing 111 in a substantially central portion in the front-rear direction. The rotary pod shelf 105 stores a plurality of pods 110. It is configured. In other words, the rotary pod shelf 105 is vertically arranged and intermittently rotated in a horizontal plane, and a plurality of shelf boards (supported by a substrate container) that are radially supported by the support 116 at each of the upper, middle, and lower positions. And a plurality of shelf plates 117 are configured to hold the pods 110 in a state where a plurality of pods 110 are respectively placed.

  A pod transfer device (substrate container transfer device) 118 is installed between the load port 114 and the rotary pod shelf 105 in the housing 111, and the pod transfer device 118 moves up and down while holding the pod 110. A pod elevator (substrate container lifting mechanism) 118a and a pod transfer mechanism (substrate container transfer mechanism) 118b as a transfer mechanism are configured. The pod transfer device 118 includes a pod elevator 118a and a pod transfer mechanism 118b. The pod 110 is transported between the load port 114, the rotary pod shelf 105, and the pod opener (substrate container lid opening / closing mechanism) 121 by continuous operation.

  A sub-housing 119 is constructed across the rear end of the lower portion of the housing 111 at a substantially central portion in the front-rear direction. A pair of wafer loading / unloading ports (substrate loading / unloading ports) 120 for loading / unloading the wafer 200 into / from the sub-casing 119 are arranged on the front wall 119a of the sub-casing 119 in two vertical stages. A pair of pod openers 121 and 121 are installed at the wafer loading / unloading ports 120 and 120 at the upper and lower stages, respectively.

  The pod opener 121 includes mounting bases 122 and 122 on which the pod 110 is placed, and cap attaching / detaching mechanisms (lid attaching / detaching mechanisms) 123 and 123 for attaching and detaching caps (lids) of the pod 110. The pod opener 121 is configured to open and close the wafer loading / unloading port of the pod 110 by attaching / detaching the cap of the pod 110 placed on the placing table 122 by the cap attaching / detaching mechanism 123.

  The sub-housing 119 constitutes a transfer chamber 124 that is fluidly isolated from the installation space of the pod transfer device 118 and the rotary pod shelf 105. A wafer transfer mechanism (substrate transfer mechanism) 125 is installed in the front region of the transfer chamber 124, and the wafer transfer mechanism 125 rotates the wafer 200 in the horizontal direction or can move the wafer 200 in the horizontal direction. Substrate transfer device) 125a and wafer transfer device elevator (substrate transfer device lifting mechanism) 125b for raising and lowering wafer transfer device 125a. As schematically shown in FIG. 2, the wafer transfer device elevator 125 b is installed between the right end of the pressure-resistant casing 111 and the right end of the front area of the transfer chamber 124 of the sub-housing 119. . By the continuous operation of the wafer transfer device elevator 125b and the wafer transfer device 125a, the tweezer (substrate holder) 125c of the wafer transfer device 125a is used as a placement portion for the wafer 200 with respect to the boat (substrate holder) 217. The wafer 200 is loaded (charged) and unloaded (discharged).

  In the rear region of the transfer chamber 124, a standby unit 126 that houses and waits for the boat 217 is configured. A processing furnace 202 is provided above the standby unit 126. The lower end portion of the processing furnace 202 is configured to be opened and closed by a furnace port shutter (furnace port opening / closing mechanism) 147.

As schematically shown in FIG. 2, a boat elevator (substrate holder) for raising and lowering the boat 217 is provided between the right end of the pressure-resistant casing 111 and the right end of the standby section 126 of the sub casing 119. (Elevating mechanism) 115 is installed. A seal cap 219 serving as a lid is horizontally installed on an arm 128 serving as a connecting tool connected to a lifting platform of the boat elevator 115, and the seal cap 219 supports the boat 217 vertically, and a lower end of the processing furnace 202. It is comprised so that a part can be obstruct | occluded.

  The boat 217 includes a plurality of holding members so that a plurality of (for example, about 50 to 125) wafers 200 are horizontally held in a state where their centers are aligned in the vertical direction. It is configured.

  As schematically shown in FIG. 2, the left end of the transfer chamber 124 opposite to the wafer transfer device elevator 125b side and the boat elevator 115 side is a cleaned atmosphere or inert gas. A clean unit 134 composed of a supply fan and a dustproof filter is installed to supply clean air 133. Between the wafer transfer device 125a and the clean unit 134, although not shown, the circumferential direction of the wafer A notch aligning device 135 is installed as a substrate aligning device for aligning the positions.

  The clean air 133 blown out from the clean unit 134 flows into the notch aligning device 135, the wafer transfer device 125a, and the boat 217 in the standby unit 126, and is then sucked in through a duct (not shown) to the outside of the housing 111. Exhaust is performed or it is circulated to the primary side (supply side) that is the suction side of the clean unit 134, and is again blown into the transfer chamber 124 by the clean unit 134.

Next, the operation of the processing apparatus of the present invention will be described.
As shown in FIGS. 2 and 3, when the pod 110 is supplied to the load port 114, the pod loading / unloading port 112 is opened by the front shutter 113, and the pod 110 above the load port 114 is connected to the pod transfer device. 118 is carried into the housing 111 from the pod loading / unloading port 112.

  The loaded pod 110 is automatically transported and delivered by the pod transport device 118 to the designated shelf 117 of the rotary pod shelf 105, temporarily stored, and then one pod opener from the shelf 117. It is conveyed to 121 and transferred to the mounting table 122, or directly transferred to the pod opener 121 and transferred to the mounting table 122. At this time, the wafer loading / unloading port 120 of the pod opener 121 is closed by the cap attaching / detaching mechanism 123, and the transfer chamber 124 is filled with clean air 133. For example, the transfer chamber 124 is filled with nitrogen gas as clean air 133, so that the oxygen concentration is set to 20 ppm or less, which is much lower than the oxygen concentration inside the casing 111 (atmosphere).

  The pod 110 mounted on the mounting table 122 has its opening-side end face pressed against the opening edge of the wafer loading / unloading port 120 on the front wall 119a of the sub-housing 119, and the cap is removed by the cap attaching / detaching mechanism 123. The wafer loading / unloading port is opened.

  When the pod 110 is opened by the pod opener 121, the wafer 200 is picked up from the pod 110 by the tweezer 125c of the wafer transfer device 125a through the wafer loading / unloading port, aligned with the notch alignment device 135, and then transferred to the transfer chamber 124. Is loaded into the standby unit 126 at the rear of the vehicle and loaded into the boat 217 (charging). The wafer transfer device 125 a that has transferred the wafer 200 to the boat 217 returns to the pod 110 and loads the next wafer 200 into the boat 217.

During the loading operation of the wafer into the boat 217 by the wafer transfer mechanism 125 in the one (upper or lower) pod opener 121, the other (lower or upper) pod opener 121 receives another pod from the rotary pod shelf 105. 110 is transferred and transferred by the pod transfer device 118, and the opening operation of the pod 110 by the pod opener 121 is simultaneously performed.

  When a predetermined number of wafers 200 are loaded into the boat 217, the lower end portion of the processing furnace 202 closed by the furnace port shutter 147 is opened by the furnace port shutter 147. Subsequently, the boat 217 holding the wafers 200 is loaded into the processing furnace 202 when the seal cap 219 is lifted by the boat elevator 115.

After loading, arbitrary processing is performed on the wafer 200 in the processing furnace 202.
After the processing, the wafer 200 and the pod 110 are discharged to the outside of the casing 111 in the reverse order of the above-described procedure except for the wafer alignment process in the notch aligner 135.

  Next, the processing furnace 202 described above will be specifically described with reference to FIG. In the following description, the case where the processing furnace 202 is applied to a vertical processing furnace that batch-processes a plurality of wafers with plasma using a batch type plasma process will be described as a representative.

  The processing furnace 202 includes a heater 304 as a heating means and a reaction tube 203 as a processing container.

  The above-described heater 304 is provided on the outer periphery of the reaction tube 203 and is configured to heat the wafer 200.

<Processing container>
The above-described reaction tube 203 is provided inside the heater 304, and the reaction tube 203 is configured to perform plasma processing on the wafer 200. The reaction tube 203 has a substantially cylindrical shape, and a processing chamber 201 for collectively processing a plurality of wafers 200 is formed therein. The upper portion of the reaction tube 203 is closed, and an opening 220 is provided at the lower portion. The opening 220 is used to insert a boat 217 as a substrate holder for holding the wafer 200 into the processing chamber 201 or from the processing chamber 201. It is configured to be extracted. The reaction tube 203 and the boat 217 are formed of a dielectric material such as quartz.

  The reaction tube 203 is provided with a gas introduction port 320 as a gas supply means, and the gas introduction port 320 is configured to supply a processing gas into the processing chamber 201. In this gas introduction port 320, a nozzle may be further raised downstream so that the processing gas can be uniformly introduced into the processing chamber 201.

  Further, the reaction tube 203 is provided with an exhaust means, and the exhaust means is configured to exhaust the processing chamber 201. That is, the exhaust means includes an exhaust pipe 317 connected to the reaction pipe 203, a pressure adjustment valve 318 provided in the exhaust pipe 317, and a vacuum pump 319 provided in the exhaust pipe 317 downstream of the pressure adjustment valve 318. The vacuum pump 319 is configured to exhaust the atmosphere in the processing chamber 201 through the exhaust pipe 317.

In the illustrated example, boats 217 are inserted into the processing chamber 201, and the boats 217 are configured in multiple stages so that a plurality of wafers 200 are stacked and held. That is, the boat 217 has a pair of first and second susceptor electrodes 305 and 306 that are stacked in layers so as to overlap each other. Plasma is generated between the electrodes 305 and 306. In the illustrated example, there are four first susceptor electrodes 305 and three second susceptor electrodes 306, and a total of seven electrodes are laminated.
The wafer 200 is held between the first and second susceptor electrodes 305 and 306 facing each other. In the illustrated example, the wafer 200 is directly held on the first and second susceptor electrodes 305 and 306. However, the wafer 200 may be floated and held between the first and second susceptor electrodes 305 and 306.
The first and second susceptor electrodes 305 and 306 are formed of a member containing a conductive material.

A cap receiver 309 as a rotating plate is provided at the lower part of the boat 217, and the cap receiver 309 is configured to support the boat 217. The cap receiver 309 is provided with a seal cap 219 serving as a lid for closing the opening 220 via a rotation shaft 310 described later. When the boat 217 is inserted into the processing chamber 201, the seal cap 219 is provided. Is configured to hermetically close the processing chamber 201.
The seal cap 219, the cap receiver 309, and the rotating shaft 366 are formed of a metal member such as stainless steel or hastelloy, and are generally grounded.

  The boat 217 is provided with a rotation mechanism that rotates the boat 217. The rotation mechanism includes a rotation shaft 310, a seal unit 311, a power transmission unit 312, and a rotation drive unit 313. The rotation force of the rotation drive unit 313 is applied to the rotation shaft 310 by the power transmission unit 312, and the seal unit 311 The boat 217 is configured to rotate by rotating the rotary shaft 310 while maintaining airtightness.

That is, the rotating shaft 310 is connected to the lower surface of the cap receiver 309 that supports the boat 217 in the vertical direction. The rotating shaft 310 has a hollow cylindrical shape, and the upper portion of the rotating shaft 310 connected to the cap receiver 309 communicates with an opening provided in the cap receiver 309 and is opened to the upper portion of the cap. The lower part of the rotating shaft 310 passes through the seal cap 219 and is open to the atmosphere.
The rotating shaft 310 is pivotally supported by the through portion of the seal cap 219. Sealing means 311, for example, a magnetic seal, is provided on the shaft support portion, and is configured so as to vacuum seal the penetrating portion of the rotating shaft 310 and maintain the airtightness in the processing chamber 201 closed by the seal cap 219. ing.
The power transmission means 312 is attached to the lower part of the rotating shaft 310 and is configured to control the rotation of the boat 217 by controlling the rotational force applied to the rotating shaft 310 from the rotation driving means 313. The power transmission means 312 is composed of, for example, a gear or a pulley / belt, and the rotation driving means 313 is composed of, for example, a motor.
In this way, the rotation mechanism is configured to rotatably support the boat 217 in the processing chamber while maintaining airtightness in the processing chamber 201.

  The first and second power supply lines 371 and 372 pass through the rotary shaft 310, and the first and second power supply lines 371 and 372 led from the top of the rotary shaft 310 are connected to the first on the boat 217. The second susceptor electrodes 305 and 306 are electrically connected. In addition, a first rotating capacitor 314a and a second rotating capacitor 314b are connected to the first and second power supply lines 371 and 372 led out from the lower part of the rotating shaft 310, respectively. The rotating capacitor 314b is configured to supply high-frequency power to the first and second susceptor electrodes 305 and 306 by capacitive coupling even when the boat 217 rotates.

The first and second power supply lines 371 and 372 may be rotary shafts 331 and 332 inserted into the cylindrical rotary shaft 310 in some embodiments. In the embodiment shown in FIG. 1, first and second rotation shafts 331 and 332 as first and second power supply lines 371 and 372 are inserted into the rotation shaft 310, and the first and second rotations are performed. The shafts 331 and 332 are coaxial with the rotation shaft 310, and the rotation shaft 310 and the first and second rotation shafts 331 and 332 are electrically insulated from each other, and rotate integrally with the hollow rotation shaft 310. It is configured as follows.

  That is, the first rotating shaft 331 is formed of a conductive material, is inserted through the center of the rotating shaft 310, and the upper portion of the first rotating shaft is connected to the first susceptor electrode 305 via the first RF feeder 307. Even when the rotating shaft lower part is connected to the first rotating capacitor 314a and the boat 217 is rotated, RF power is supplied from the first rotating shaft 331 to the first susceptor electrode 305 via the first rotating capacitor 314a by capacitive coupling. It is configured to be able to.

  The second rotating shaft 332 is hollow and formed of a conductive material. The second rotating shaft 332 is inserted into the cylindrical rotating shaft 310 so as to concentrically surround the first rotating shaft 331, and the upper portion of the second rotating shaft is the second RF feeder. The first susceptor electrode 305 is connected to the second susceptor electrode 306 via 308, the lower part of the second rotation shaft is connected to the second rotation capacitor 314b and the boat 217 is rotated. The different RF powers can be supplied from the second rotating shaft 332 to the second susceptor electrode 306 via the second rotating capacitor 314b.

  Furthermore, an insulator is provided between the first rotating shaft 331 and the second rotating shaft 332, and between the second rotating shaft 332 and the hollow rotating shaft 310. These insulators are the first and second rotating shafts. The rotary shafts 331 and 332 and the hollow rotary shaft 310 are configured to be insulated from each other. These insulators constitute cylindrical insulating sleeves 333 and 334 disposed coaxially with the hollow rotary shaft 310. Therefore, the first rotating shaft 331, the insulating sleeve 333, the second rotating shaft 332, and the insulating sleeve 334 are coaxially arranged from the center side inside the hollow rotating shaft 310.

  A high frequency power supply means is connected to the first rotary capacitor 314a and the second rotary capacitor 314b, and the high frequency power supply means supplies high frequency powers of different phases to the first and second susceptor electrodes 305 and 306 separately. It is configured. That is, the high frequency power supply means includes an oscillator 315, a matching unit 316 connected to the non-grounded side of the oscillator 315, a primary side connected between the matching unit 316 and the grounded side of the oscillator 315, and both secondary sides are ungrounded The isolation transformer 330 is configured to float the secondary side output from the ground so that the high-frequency power output from the oscillator 315 can be output from the first, It can be applied to the first and second susceptor electrodes 305 and 306 via the two-rotation capacitors 314a and 314b.

  As a result, even when the boat 217 is rotated, RF power can be supplied to the first and second susceptor electrodes 305 and 306 via the first and second rotating capacitors 314a and 314b.

  The main bodies of the first and second rotating capacitors 314a and 314b need to be fixed, but are preferably attached to the seal cap 219 and fixed.

  In addition, in order to secure the largest possible capacitance, the rotating capacitor can be designed with a particular shape so that the relative permittivity and area of the counter electrode are both large and the gap between the counter electrodes is small. preferable. For example, as in the illustrated example, one electrode attached to the seal cap 219 and the other electrode attached to the rotating shaft so as to face each other may be interdigitated, or may be opposed to each other although not shown. The area of one electrode attached to the seal cap 219 side of the two electrodes is made larger than the other electrode attached to the rotating shaft side, and the end of one electrode is bent so that the other electrode is covered completely It is good to use a bag-shaped electrode.

  As described above, the illustrated embodiment is configured to supply high-frequency power having different phases between the first susceptor electrode 305 and the second susceptor electrode 306 via the first rotation shaft 331 and the second rotation shaft 332. ing.

  It should be noted that control of each part such as a heater 304, a pressure adjusting valve 318, a rotating means 313, an oscillator 315, and a valve (not shown) provided in the gas introduction port 320 in each step described later is performed by a controller 300 serving as a control means.

  Next, a method of performing plasma processing on the wafer 200 as one step of the semiconductor device manufacturing process using the above-described vertical processing furnace will be described.

  With the processing chamber 201 at atmospheric pressure, the boat elevator 115 (see FIG. 2) lowers the seal cap 219 to unload the boat 217 from the processing chamber 201. At this time, the temperature of the heater 304 is lowered. However, if the temperature is lowered too much, it takes a considerable time for the temperature to be increased to a predetermined value within the processing chamber 201 and stabilized after the loading of the wafer 200 is completed. Therefore, the temperature is usually lowered to a temperature that does not hinder the transfer of the wafer 200, and the transfer is performed while maintaining the temperature.

  A plurality (one batch) of wafers 200 are transferred onto the first susceptor electrode 305 and the second susceptor electrode 306 by the mutual operation of the boat 217 and the wafer transfer mechanism 125 (see FIGS. 2 and 3). After the wafer transfer, the seal cap 219 is raised to load the boat 217 into the processing chamber 201, and the processing chamber 201 is sealed with the seal cap 219.

  Next, the inside of the processing chamber 201 is evacuated by the vacuum pump 319, and the controller 300 controls the pressure of the processing chamber 201 to be a predetermined processing pressure lower than the atmospheric pressure. Further, the boat 217 is rotated at a predetermined rotation speed by the rotation mechanism.

  Further, power is supplied to the heater 304 to heat the members in the processing chamber 201 such as the boat 217, the first and second susceptor electrodes 305 and 306 in the reaction tube 203, and the wafer 200 is brought to a predetermined processing temperature. Control as follows.

  At the same time, the gas inside the processing chamber 201 is exhausted by the vacuum pump 319 through the exhaust pipe 317. When the wafer 200 reaches a predetermined temperature, the processing chamber 201 under reduced pressure is evacuated while introducing the processing gas from the gas introduction port 320. At this time, the pressure in the processing chamber 201 is held at a constant value by the pressure adjustment valve 318.

  When the inside of the processing chamber 201 reaches a predetermined pressure, the rotation means 313 is controlled to rotate by the controller 300 and the boat 217 is rotated. Then, while rotating the boat 217, the high frequency power output from the oscillator 315 is supplied from the insulating transformer 330 through the first and second rotating capacitors 314a and 314b and the first and second RF feeders 307 and 308, 306 is supplied to generate plasma between the susceptor electrodes 305 and 306. The frequency of the high frequency power supplied to the first and second RF feeders 307 and 308 is about 13.56 MHz or 400 KHz.

  Note that the number of the susceptor electrodes 305 and 306 is determined by the space between the susceptor electrodes 305 and 306 determined by the plasma generation conditions and the like, and the restriction on the size of the processing chamber 201 in the height direction.

Reactive species are generated from the processing gas by the plasma generated between the first and second susceptor electrodes 305 and 306, and a film forming process is performed on the wafer 200 by the reactive species.
As the processing temperature, for example, when the plasma processing is a film forming process, the room temperature (for example, 20 ° C.) to 850 ° C. of the clean room is exemplified, and the processing pressure is 1-1000 Pa.

  When the plasma processing of the wafer 200 is completed, the residual gas in the processing chamber 201 is removed by evacuation, purging with an inert gas, and the like. After the temperature in the processing chamber 201 is lowered to a predetermined temperature, the boat 217 is moved to the processing chamber 201. The boat 217 waits at a predetermined position until all the wafers 200 held in the boat 217 are cooled. When the wafer 200 held in the waiting boat 217 is cooled to a predetermined temperature, the wafer is collected by the wafer transfer mechanism 125 or the like.

  According to the present embodiment, even when plasma processing is performed while the boat 217 is rotated by the rotating means 313, the AC power output from the oscillator 315 is further passed through the matching unit 316 and the insulating transformer 330, and the first and second rotating capacitors. A plurality of susceptor electrodes installed on the rotating boat 217 can be supplied via 314a and 314b. Therefore, the in-plane uniformity of the plasma treatment of the wafer 200 and the uniformity between the surfaces can be further improved.

  In addition, since high-frequency power having different phases is separately supplied to the first and second susceptor electrodes 305 and 306 via the first and second rotating capacitors 314a and 314b, the first and second susceptor electrodes 305 are supplied. , 306 can be applied with a large voltage, and plasma discharge can be easily performed between the first and second susceptor electrodes 305, 306. Therefore, the in-plane uniformity of the plasma treatment of the wafer 200 can be improved, and the inter-surface uniformity can also be improved. In particular, when high-frequency power is applied to the first and second susceptor electrodes 305 and 306 so that the phases are different by 180 degrees, plasma discharge can be performed more easily, and in-plane uniformity of the plasma processing of the wafer 200, and also the surface The uniformity can be further improved.

  Further, according to the present embodiment, since the first and second rotating shafts 331 and 332 are insulated from the hollow rotating shaft 310, part of the electric field to be applied to the first and second susceptor electrodes 305 and 306. However, since the plasma does not spread except between the first and second susceptor electrodes 305 and 306 from the hollow rotary shaft 310 through the seal cap 219 toward the housing 111 (see FIGS. 2 and 3), the first In addition, a decrease in plasma density between the second susceptor electrodes 305 and 306 can be suppressed. Accordingly, it is possible to improve the in-plane uniformity of the plasma processing of the wafer 200 and further the uniformity between the surfaces.

  The first and second rotating shafts 331 and 332 are preferably provided coaxially with the hollow rotating shaft 310. By providing the first and second rotating shafts 331 and 332 coaxially with the hollow rotating shaft 310, the axis of the rotating shaft of the first and second rotating capacitors 314 a and 314 b is the first and second rotating shafts 331 and 332. The first and second rotating capacitors 314a and 314b can be easily attached.

Although the above embodiment is for a batch type apparatus, the present invention is also applicable to a single wafer type apparatus.
The present invention can also be applied to a processing apparatus that etches the surface of a substrate such as a silicon wafer using plasma, forms a thin film, or modifies the surface.

(Comparative example)
Next, a comparative example will be described.

In the comparative example, two supply lines are passed through the rotary shaft, one supply line is grounded and connected to the first electrode, and the other non-grounded supply line is connected to the second via a rotatable capacitor. Connected to the electrode. By supplying high-frequency power between the two electrodes via a single rotating capacitor, plasma processing can be performed while rotating the substrate to be processed.

Next, a comparative example will be described in more detail with reference to the drawings.
FIG. 4 is a configuration diagram showing a vertical processing furnace of a comparative example. The basic components of the vertical processing furnace are the same as the corresponding components of the vertical processing furnace of the embodiment described with reference to FIG.

  In the comparative example, a nozzle 322 is provided downstream of the gas introduction port 320, and this nozzle 322 is provided inside the processing chamber 201 in the vertical direction along the side surface of the reaction tube 203. The nozzle 322 is provided with a plurality of gas supply pores 321, and the size of the plurality of gas supply pores 321 is adjusted so as to supply the processing gas evenly in the height direction. The processing gas can be introduced evenly.

  In the comparative example, the wafer 200 is configured to be disposed between the electrodes 305 and 306. That is, the wafers 200 are locked in the locking grooves provided in multiple stages in the boat 217 instead of on the electrodes.

  Further, in the comparative example, the first and second supply lines 307 and 308 are passed through the inside of the rotary shaft 310 that is passed through the seal cap 219 via the seal means 311.

  By the first supply line 307, the first electrode 305 is connected to the oscillator 315 via the rotating capacitor 314 and the matching unit 316, and the second electrode 306 is a second supply line that is the ground side of the oscillator 315. (Ground line) 308 is connected, so that high-frequency power output from the oscillator 315 can be applied between the first and second electrodes 305 and 306 via the matching unit 316.

  In such a configuration, the ground side of the oscillator 315 on the side where the rotating capacitor 314a is not provided is electrically connected through a ground (earth) path from the rotating shaft 310, so that the oscillator 315 is not grounded. It is inevitable that the electric field from the first electrode 305 on the side moves to the ground (earth), and the plasma spreads to other than between the first and second electrodes 305 and 306 and the plasma density decreases. Therefore, if plasma is generated and processed in this state, the processing state becomes non-uniform.

  Further, since the second electrode 306 is connected to the grounded second supply line 308, the high-frequency power applied to the first electrode 305 is transferred to the seal cap around the rotating shaft 310 that is also grounded. The escape is inevitable and the plasma density is reduced. If plasma is generated and processed in this state, the processing state becomes non-uniform. Therefore, the in-plane uniformity of the plasma processing of the wafer 200 is inferior to the embodiment.

The preferred embodiments of the present invention will be described below.
In an apparatus for stacking substrates to be processed in multiple stages in a processing chamber under reduced pressure and performing batch processing using plasma, two systems are provided inside a hollow rotating shaft provided in a seal cap for rotating a boat. The RF introduction port is provided coaxially, and RF power can be introduced via a rotating capacitor rotatably provided at each RF introduction port, so that the uniformity of the substrate to be processed can be secured. You can rotate the boat.

  Furthermore, when the first electrode and the second electrode are plate-shaped susceptor electrodes and the substrate to be processed is held on the susceptor electrode, a substrate holding body for holding the substrate is provided separately from the electrodes. To simplify the structure.

  Preferably, the first system RF introduction port passes through the center of the hollow rotation shaft, the second system introduction port passes through the hollow rotation shaft so as to concentrically surround the first system RF introduction port, and the first, Insulation is performed between the second RF introduction port and between the second RF introduction port and the hollow rotary shaft. Since high-frequency power having different phases can be separately introduced into the first electrode and the second electrode, a high applied voltage corresponding to the phase can be applied, and plasma discharge can be easily caused.

  Preferably, the first rotating capacitor is rotatably provided between one end of the high frequency power supply means for supplying high frequency power and the first RF introduction port, and the second rotating capacitor is provided with the high frequency power supply. A high-frequency power having a phase different from that of the one end and the other end of the high-frequency power supply means is provided between the other end of the high-frequency power supply means and the second high-frequency power introduction port. And separately introduced into the second electrode. Since high-frequency powers having different phases are separately introduced into the first electrode and the second electrode, a high applied voltage corresponding to the phase can be applied, and plasma discharge can be easily caused.

  Preferably, the high-frequency power of the high-frequency power supply means is connected to the first rotating capacitor and the second rotating capacitor via an insulating transformer. Since the first rotating capacitor and the second rotating capacitor high-frequency power are introduced through the insulating transformer, the first electrode and the second electrode are floated from the ground, and the phase is shifted, so that a higher applied voltage can be applied to the first electrode and the second electrode. It becomes possible to apply between two electrodes, and plasma discharge can be caused more easily.

It is a schematic longitudinal cross-sectional view for demonstrating the vertical processing furnace of the substrate processing apparatus of one Embodiment in this invention. 1 is a schematic perspective view for explaining a substrate processing apparatus according to an embodiment of the present invention. It is a schematic longitudinal cross-sectional view for demonstrating the substrate processing apparatus of one Embodiment in this invention. It is a schematic longitudinal cross-sectional view for demonstrating the vertical type processing furnace of the substrate processing apparatus of a comparative example. It is a schematic longitudinal cross-sectional view for demonstrating the vertical processing furnace of the substrate processing apparatus of a prior art example.

Explanation of symbols

200 wafer (substrate to be processed)
201 processing chamber 203 reaction tube (processing vessel)
217 boat (substrate holder)
219 Seal cap (lid)
220 Opening 305 First susceptor electrode 306 Second susceptor electrode 310 Rotating shaft 314a First rotating capacitor 314b Second rotating capacitor 315 High-frequency oscillator (power supply means)
317 Exhaust pipe 320 Gas introduction port (gas supply means)
329 Vacuum pump 331 First rotating shaft 332 Second rotating shaft 333, 334 Insulating sleeve (insulator)
371 First power supply line 372 Second power supply line

Claims (2)

A processing container having an opening and forming a processing chamber therein;
Gas supply means for supplying gas into the processing chamber;
Exhaust means for exhausting the processing chamber;
A substrate holder that is inserted into the processing chamber from the opening and holds a substrate to be processed;
At least one pair of electrodes for plasma generation laminated on the substrate holder, the first electrode and the second electrode on which the substrate to be processed is disposed between the electrodes;
A rotating shaft for rotatably supporting the substrate holder in the processing chamber;
A lid that pivotally supports the rotating shaft and closes the opening;
A first power supply line and a second power supply line that are introduced into the processing chamber through the rotating shaft and electrically connected to the first electrode and the second electrode, respectively.
A first rotating capacitor and a second rotating capacitor respectively connected to the first power supply line and the second power supply line led out of the processing chamber through the rotating shaft;
High-frequency power supply means for separately supplying high-frequency power of different phases to the first electrode and the second electrode via the first rotating capacitor and the second rotating capacitor;
A substrate processing apparatus comprising: A processing container having an opening and forming a processing chamber therein;
Gas supply means for supplying gas into the processing chamber;
Exhaust means for exhausting the processing chamber;
A substrate holder that is inserted into the processing chamber from the opening and holds a substrate to be processed;
At least one pair of electrodes for plasma generation laminated on the substrate holder, the first electrode and the second electrode on which the substrate to be processed is disposed between the electrodes;
A cylindrical rotating shaft for rotatably supporting the substrate holder in the processing chamber;
A lid that rotatably supports the cylindrical rotation shaft and closes the opening;
A conductive first rotating shaft that is inserted into the center of the cylindrical rotating shaft and is electrically connected to the first electrode inside the processing chamber;
A conductive and hollow second rotating shaft that is inserted into the cylindrical rotating shaft so as to concentrically surround the first rotating shaft and is electrically connected to the second electrode;
An insulator for insulating between the first rotating shaft and the second rotating shaft and between the second rotating shaft and the cylindrical rotating shaft;
High-frequency power supply means for separately supplying high-frequency power of different phases between the first electrode and the second electrode via the first rotating shaft and the second rotating shaft;
A substrate processing apparatus comprising:

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