JP4948088B2 - Semiconductor manufacturing equipment - Google Patents

Description

  The present invention relates to a semiconductor manufacturing apparatus, and more particularly to a semiconductor manufacturing apparatus that performs plasma processing on a plurality of substrates simultaneously.

  Conventionally, a batch type plasma processing apparatus is known as a semiconductor manufacturing apparatus that carries a plurality of substrates, for example, a boat holding silicon wafers into a processing chamber and performs plasma processing on the plurality of wafers simultaneously (for example, Patent Document 1).

An example of a heat treatment furnace constituting the batch type plasma processing apparatus described in Patent Document 1 is shown in FIGS. FIG. 7 is a sectional view taken along the line XX of FIG. As shown in FIGS. 6 and 7, in the heat treatment furnace of the conventional example, a pair of electrode protection tubes 8 are provided vertically along the inner wall surface of the process tube 7. The electrode protection tube 8 is bent downward toward the outside of the process tube 7 and penetrates the process tube 7, and a pair of electrodes 9 are inserted into both the electrode protection tubes 8 from below the process tube 7.
Further, on the inner periphery of the process tube 7, a bowl-shaped partition wall 11 that forms the plasma chamber 10 is installed so as to airtightly surround both electrode protection tubes 8. In the partition wall 11, through holes 12 as a plurality of air outlets are arranged so as to face between the wafers 6 stacked vertically in the process tube 7.

  In such a conventional heat treatment furnace, a processing gas (process gas) is supplied to the plasma chamber 10, and after maintaining the plasma chamber 10 at a predetermined pressure, high-frequency power is supplied between the pair of electrodes 9 by the high-frequency power source 13. Is done. Thereby, plasma 14 is formed in the plasma chamber 10, the processing gas is activated, and active species (radicals) 15 are generated. The electrically neutral active species 15 are blown out from the through holes 12 formed in the partition wall 11 and supplied to the processing chamber 16 a, thereby contacting the wafers 6 held in the boat 3. The active species 15 in contact with the wafer 6 performs wafer processing such as film formation on the surface of the wafer 6.

  However, in the conventional heat treatment furnace using the plasma source composed of the pair of electrodes 9 described above, since plasma is generated in the peripheral portion of the wafer 6, it is difficult to ensure a highly uniform plasma density in the wafer 6 plane. It is. In addition, since the distance from the plasma chamber 10 to the wafer 6 is long, depending on the process gas type, the active species generated at the corner may disappear during the supply and be deactivated, and the concentration of the active species is lowered for this reason. There is also a problem that the wafer processing efficiency is not good. Further, there is a concern that the surface portion of the electrode protection tube 8 and the inner wall of the plasma chamber 10 are sputtered by high energy ions in the plasma and cause particles.

Patent Document 1 discloses a heat treatment furnace using a plasma source including parallel plate electrodes instead of a pair of electrodes as another example of the heat treatment furnace. A plasma source composed of parallel plate electrodes can generate a high-density plasma having an electron density of about 10 ¹¹ to 10 ¹³ cm ⁻³ than a plasma source using a pair of electrodes. The configuration is a method in which parallel plate electrodes are installed outside the reaction tube, and by applying a high frequency to these electrodes, capacitively coupled plasma (CCP) is generated and active species are sent into the processing chamber. . A similar method can also be seen in Patent Document 2. As shown in FIG. 8, the device described in Patent Document 2 is provided with two parallel plate electrodes 76 in a plasma generation unit 68 adjacent to the processing vessel 42, and a power supply line 80 is interposed between these parallel plate electrodes 76. In this method, a high frequency power from a high frequency power supply 78 is applied to generate a capacitively coupled plasma to send active species into the processing vessel 42.

  According to this capacitively coupled plasma (CCP), it is possible to meet the demand for higher integration of semiconductor devices and miniaturization processes for higher performance, which have become increasingly severe in recent years. From the viewpoint of improvement, it is also possible to reduce the thermal history in the semiconductor device manufacturing process.

  However, in capacitively coupled plasma (CCP), the ion temperature in the plasma is high, and ions with high energy collide with the quartz wall that constitutes the processing chamber, and sputter the film on the quartz inner wall or even the quartz inner wall. There is a risk that. Moreover, if high-frequency power output is increased to generate high-density plasma in the center of the wafer, the plasma density (= ion density) inevitably increases around the wafer, that is, near the quartz wall of the processing chamber, and the inner wall of the quartz. There is a problem that the probability of sputtering is further increased.

Therefore, a substrate processing apparatus that performs a series of reaction processes using an electron beam excited plasma (EBEP) source has been proposed. In this method, a plasma generation chamber is provided on a side surface of a substrate holder (boat) in a processing container, and a processing gas is supplied to the plasma generation chamber to generate plasma. In addition, an electron supply device having an anode and a grid is provided in the plasma generation chamber. Using this electron supply device, electrons are extracted from the plasma in the plasma generation chamber to the processing chamber, and a plurality of wafers held by the substrate holder are interposed between the plurality of wafers. The substrate is supplied and subjected to plasma treatment. According to this, the above-described plasma density in the substrate surface can be made uniform.
JP 2004-289166 A JP 2004-343017 A

However, the conventional technique using the above-described electron supply device still has a problem that the problem of sputtering cannot be solved. That is, there is a problem that ions are accelerated in the plasma generation chamber, collide with the walls, cause sputtering, generate particles, and contaminate the substrate. In particular, an apparatus for manufacturing a plurality of substrates has been a big problem because contamination reaches a plurality of substrates.
An object of the present invention is to provide a semiconductor manufacturing apparatus capable of solving the above-described problems of the prior art and suppressing the occurrence of sputtering to prevent the generation of particles.

  According to an aspect of the present invention, a processing container that processes a plurality of substrates, a substrate holder that is accommodated in the processing container and holds the plurality of substrates in multiple stages, and plasma provided on a side surface of the substrate holder A second gas supply for supplying a second gas between the generation chamber, a first gas supply unit for supplying a first gas into the plasma generation chamber, and a plurality of substrates held by the substrate holder; And an electrode that is provided outside the processing vessel and excites the first gas supplied into the plasma generation chamber by inductive coupling to generate plasma, and between the electrode and the plasma generation chamber A shield provided in contact with the ground, and provided in the plasma generation chamber, emits electrons of the plasma generated in the plasma generation chamber between the plurality of substrates in the processing container, and between the substrates Supplied to the first The semiconductor manufacturing apparatus and an electronic supply device for plasma-exciting gas is provided.

  According to the present invention, generation of particles can be suppressed by suppressing the occurrence of sputtering.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 5 is an overall perspective view of an embodiment of the semiconductor manufacturing apparatus of the present invention. As shown in FIG. 5, the semiconductor manufacturing apparatus A constitutes a batch type plasma apparatus. The batch type plasma apparatus has a housing 101. A cassette stage 105 is provided on the front side of the inside of the casing 101 as a holder transfer member for transferring the cassette 100 as a substrate storage container to and from an external transfer device (not shown). Is provided with a cassette elevator 115 as an elevating means, and a cassette transfer machine 114 as a conveying means is attached to the cassette elevator 115. A cassette shelf 109 as a means for placing the cassette 100 is provided on the rear side of the cassette elevator 115, and a spare cassette shelf 110 is also provided above the cassette stage 105. A clean unit 118 is provided above the spare cassette shelf 110 so that clean air is circulated inside the housing 101.

  A heat treatment furnace 5 is provided above the rear portion of the casing 101, and a substrate holder that holds a semiconductor silicon wafer (hereinafter simply referred to as a wafer 6) as a substrate to be processed in a horizontal posture in multiple stages below the heat treatment furnace 5. A boat elevator 121 is provided as an elevating means for elevating and lowering the boat 3 as a heat treatment furnace 5. A seal cap 125 as a lid is attached to the tip of the elevating member 122 attached to the boat elevator 121 to support the boat 3 vertically. Between the boat elevator 121 and the cassette shelf 109, a transfer elevator 113 as an elevating means is provided, and a wafer transfer machine 112 as a transfer means is attached to the transfer elevator 113. Next to the boat elevator 121, a furnace port shutter 116 having an opening / closing mechanism and closing means for closing the wafer loading / unloading port 131 on the lower side of the heat treatment furnace 5 is provided.

  The cassette 100 loaded with the wafer 6 is loaded into the cassette stage 105 from an external transfer device (not shown) in an upward posture, and is rotated by 90 ° on the cassette stage 105 so that the wafer 6 is in a horizontal posture. Further, the cassette 100 is transported from the cassette stage 105 to the cassette shelf 109 or the spare cassette shelf 110 by cooperation of the raising / lowering operation of the cassette elevator 115, the transverse operation, the advance / retreat operation of the cassette transfer machine 114, and the rotation operation.

  The cassette shelf 109 has a transfer shelf 123 in which the cassette 100 to be transferred by the wafer transfer device 112 is stored. The cassette 100 used for transferring the wafer 6 is transferred by the cassette elevator 115 and the cassette transfer device 114. Transferred to the transfer shelf 123.

  When the cassette 100 is transferred to the transfer shelf 123, the wafers 6 are transferred from the transfer shelf 123 to the lowered boat 3 by the cooperation of the forward / backward movement operation, the rotation operation of the wafer transfer device 112, and the lifting / lowering operation of the transfer elevator 113. Is transferred.

  When a predetermined number of wafers 6 are transferred to the boat 3, the boat 3 is inserted into the heat treatment furnace 5 by the boat elevator 121, and the wafer loading / unloading port 131 of the heat treatment furnace 5 is airtightly closed by the seal cap 125. In the heat treatment furnace 5 that is hermetically closed, the wafer 6 is heated and a processing gas is supplied into the heat treatment furnace 5 so that the wafer 6 is processed.

  When the processing on the wafer 6 is completed, the wafer 6 is transferred from the boat 3 to the cassette 100 of the transfer shelf 123 by the reverse procedure of the above-described operation, and the cassette 100 is transferred from the transfer shelf 123 by the cassette transfer device 114. It is transferred to the cassette stage 105 and carried out of the housing 101 by an external transfer device (not shown).

  The furnace port shutter 116 hermetically closes the wafer loading / unloading port 131 of the heat treatment furnace 5 when the boat 3 is in the lowered state, and prevents outside air from being caught in the heat treatment furnace 5.

  The transport operation of the cassette transfer machine 114 and the like is controlled by the transport control means 124.

FIG. 1 is a longitudinal sectional view showing the configuration of the heat treatment furnace 5 described above, FIG. 2 is a view taken in the direction of arrow Y in FIG. 1, and FIG. 3 is a sectional view taken along line XX in FIG.
As shown in FIGS. 1 and 3, the heat treatment furnace 5 extends vertically on the inner wall surface of the process tube 7 as a cylindrical evacuable processing container with a closed top, as in the conventional semiconductor manufacturing apparatus. A partition wall 11 is provided. A plasma generation chamber 17 partitioned in the process tube 7 is formed by the partition wall 11 and the inner wall of the process tube 7.
The partition wall 11 is concentric with the process tube 7, and includes a central wall 11 a having a circular arc shape along the outer periphery of each wafer 6, and a connection wall 11 b that connects the central wall 11 a to the inner wall of the process tube 7. Yes.
A plurality of wafers 6 are placed side by side on the respective placement portions 4 of the boat 3 so that the front and back surfaces face each other. More specifically, the boat 3 is arranged at the center of the process tube 7 so that the centers of the wafers 6 are aligned on the central axis of the process tube 7. The aforementioned plasma generation chamber 17 is provided on the side surface of the boat 3.
The process tube 7, the partition wall 11, and the boat 3 described above are made of, for example, quartz.

A first plasma source is provided outside the process tube 7 at a position corresponding to the plasma generation chamber 17. The first plasma source is, for example, an inductive coupled plasma (ICP) source in which a loop electrode 22 made of a metal or carbon rod is provided on the outer wall of the plasma generation chamber 17 shown in FIG. It is configured. A grounded metal shield 23 is interposed between the loop-shaped electrode 22 and the outer wall of the process tube 7. Both ends of the loop electrode 22 are connected to the high frequency power supply 13. The ICP plasma source excites the first gas (processing gas) supplied from the gas supply pipe 31 serving as the first gas supply unit into the plasma generation chamber 17, and the first gas is supplied into the plasma generation chamber 17. Plasma is generated. The density of electrons generated by the ICP plasma source is, for example, about 10 ¹⁰ to 10 ¹² / cm ³ in actual measurement.

  The configuration of the ICP plasma source according to the present embodiment mainly includes an ICP electrode 22 connected to a high-frequency power source 13 and a grounded shield 23.

  In this embodiment, the EBEP method is used as the second plasma source in the vertical batch plasma processing apparatus. The EBEP method is a method in which electrons are directly irradiated between the wafers 6 by an electron gun 41 serving as an electron supply device, and a processing gas is ionized in the immediate vicinity of the wafers 6 to generate second plasma.

  A plurality of through holes 12 through which electrons are blown out are arranged in the central wall 11 a of the partition wall 11 constituting the plasma generation chamber 17. The through-hole 12 is between a plurality of wafers 6 stacked in multiple stages in the vertical direction, and between adjacent wafers 6 so that an electron beam can be ejected in a direction along the surface of the wafer 6, for example, parallel to the surface. Are arranged at equal intervals in the vertical direction. The through hole 12 is arranged so that the electron beam passes through the center between the wafers 6, but may be arranged so that the electron beam passes in a direction slightly deviated from the center of the wafer 6. The partition 11 hermetically partitions the processing chamber 29 and the plasma generation chamber 17 formed in the process tube 7 except for the through hole 12.

A flat grid electrode 19 and an anode electrode 20 extending in the vertical direction are provided in the plasma generation chamber 17. The grid electrode 19 and the anode electrode 20 are arranged to face each other, and the anode electrode 20 is provided to face the wall on the center side of the heat treatment furnace 5 in the partition wall 11. Both the grid electrode 19 and the anode electrode 20 have electron passage holes 19a and 20a corresponding to the through holes 12 as shown in FIG. The grid electrode 19 is connected to the negative electrode side of the DC power source 21, and the anode electrode 20 is connected to the anode side of the DC power source 21. Therefore, when a voltage is applied between the grid electrode 19 and the anode electrode 20 by the DC power source 21, an electric field for accelerating electrons is generated between the electron passage hole 19a and the electron passage hole 20a.
These grid electrode 19, anode electrode 20, and DC power supply 21 mainly constitute an electron supply device (electron gun) 41.

The process tube 7 includes a gas supply pipe 31 as a first gas supply section for supplying a first gas (processing gas) into the plasma generation chamber 17 and an exhaust pipe 32 for exhausting the inside of the process tube 7. Is provided. Although not shown, a gas supply pipe is also provided as a second gas supply unit for supplying a second gas (processing gas) directly into the processing chamber 29 in order to ensure a process that does not use plasma. ing. In the case of a process using only plasma gas, the second gas supply unit is the same as the first gas supply unit.
The gas supply pipe 31 supplies a processing gas into the processing chamber 29 through the plasma generation chamber 17. A gas supply system 33 including a gas supply source, piping and valves is connected to the gas supply pipe 31 in order to supply a processing gas. The gas supply pipe 31 and the gas supply system 33 constitute a processing gas supply apparatus. A pump 34 is connected to the exhaust pipe 32 through an automatic pressure control valve and piping so that the process tube 7 can be exhausted.

  The boat 3 is supported by bearings 35 so that the boat 3 can rotate around the center of the wafer 6. The boat 3 is rotated by a rotation drive mechanism 36 as a rotation device.

  The electrode 22 has a height U sufficient to substantially cover the entire height of the boat 3 in order to uniformly plasma process all of the plurality of wafers 6 mounted on the boat 3 in the height direction. A letter-shaped loop antenna is used. In the embodiment, the electrode 22 as a loop antenna has a rectangular loop structure outside the position corresponding to the plasma generation chamber 17 of the process tube 7. The plasma is ICP (inductively coupled plasma), and plasma can be easily generated in a low pressure range of 1 to 100 Pa compared to CCP (capacitively coupled plasma). Since the electrode 22 is installed outside the process tube 7, it does not require an electrode protection tube that is necessary when the electrode 22 is installed inside the process tube 7.

  The high frequency power supply 13 for applying a high frequency to the electrode 22 only needs to generate the first plasma in the plasma generation chamber 17 only for taking out the electron beam, so that a high output high frequency power is applied to the electrode 22. There is no need. For example, depending on the wafer processing conditions, a low output of 100 W or less is sufficient as the power applied to the electrode 22 if an electron beam of several tens of mA is taken out under a pressure of 1 Pa. Therefore, there is little concern that quartz or the like constituting the inner wall of the plasma generation chamber 17 is sputtered.

  The shield 23 is made of metal and is provided between the U-shaped electrode 22 and a part of the outer wall 7 a of the process tube 7 constituting the plasma generation chamber 17. The shield 23 is shaped so as to hide the U-shaped electrode 22 from any position inside the plasma generation chamber 17 when viewed from the U-shaped electrode 22. In the illustrated example, the overall shape of the shield 23 is a rectangular shape protruding from the outer edge of the U-shaped electrode 22. The overall shape of the shield 23 is not limited to a rectangular shape, and may be an oval shape. The shield 23 is not composed of a single large shield plate, but is composed of, for example, a plurality of pieces 23a obtained by subdividing the large shield plate into a square shape. In the illustrated example, the pieces 23a are arranged in 13 rows × 3 columns = 39 pieces. All the pieces 23a are grounded by being electrically connected by a connecting portion 30 that is narrower than the width of the piece 23a. The shape of the piece 23a may be a triangular shape, a pentagonal polygonal shape or a circular shape.

The operation of the heat treatment furnace 5 configured as described above will be described.
The boat 3 descends from the heat treatment furnace 5, and a plurality of wafers 6 are loaded on the boat 3 by the wafer transfer device 112. The boat 3 loaded with the wafers 6 is inserted into the heat treatment furnace 5, and the heat treatment furnace 5 is hermetically closed by the seal cap 125.
Then, while the processing gas is supplied from the gas supply pipe 31 to the processing chamber 29 through the plasma generation chamber 17, vacuum evacuation is performed by the pump 34, so that an atmosphere of gas and pressure suitable for plasma processing is obtained.

  While the process tube 7 is heated by the heater 16 to maintain the wafer at the processing temperature, the high frequency power supply 13 is operated to flow a large current to the loop electrode 22. Ar gas is supplied from the gas supply pipe 31 to the plasma generation chamber 17. High frequency electromagnetic induction is generated in the plasma generation chamber 17 to form a first plasma. At this time, high-density and large-area plasma can be generated. The DC power supply 21 is operated to apply a DC voltage between the grid electrodes 19 and 20. Then, as will be described below, electrons are extracted from the first plasma produced by the ICP plasma source.

As shown in FIG. 4, ions 25 (A ⁺ ions in FIG. 3) and electrons 26 (e in FIG. 3) are mixed in the plasma generated in the plasma generation chamber 17, and the neutrality is maintained as a whole. Yes. When a voltage is applied between the grid electrode 19 and the anode electrode 20 by the DC power source 21, the electrons 26 in the plasma are subjected to trajectory correction by an electric field created by the negative voltage applied to the grid electrode 19. It converges on the passage hole 19a. Then, the electric field generated by the positive voltage (acceleration voltage) applied to the anode electrode 20 is accelerated toward the electron passage hole 20a of the anode electrode 20. The accelerated electrons are turned into a bundle of electrons, that is, an electron beam (Electron-beam) 24, drawn out from the through hole 12 of the partition wall 11 into the processing chamber 29, and launched between the wafers 6 and 6. The emitted electron beam 24 excites or ionizes the plasma gas 28 (B molecule in FIG. 3) with a certain probability in the immediate vicinity of the surface of the wafer 6. The excited or ionized second plasma gas 27 (B ^{+ in} FIG. 3) processes the surface of the wafer 6.

  At this time, the rotation of the boat 3 by the rotation drive mechanism 36 ensures the uniformity of the electron beam within the wafer 6 and between the wafers in the height direction (between the wafer surfaces). A plurality of wafers 6 are uniformly processed as a whole by contacting with the plasma gas 27 having a uniform surface.

  By the way, since an electrostatic field is often strongly induced in the radial direction of the loop antenna as the electrode 22, ions in the plasma in the plasma generation chamber 17 are accelerated and collide with the inner wall of the process tube 7, and the dielectric surface is sputtered. Particles are generated. That is, there is a problem that the electric field induced in the plasma generation chamber 17 entrains the plasma, the inner wall of the plasma generation chamber 17 is sputtered, particles are generated, and the wafer 6 is contaminated.

  With respect to this problem, in the embodiment, the shield 23 is provided between the electrode 22 and the outer wall of the process tube 7 and is grounded. The grounded shield 23 blocks the penetration of the electric field generated in the electrode 22 into the plasma generation chamber 17, so that sputtering of the inner wall of the plasma generation chamber 17 by ions in the plasma 18 can be reliably suppressed. Therefore, as compared with the conventional example described above, the generation of foreign matter due to the sputtering action is suppressed, the generation of particles is small, and the probability that particles fall on the wafer can be reduced.

In addition, since the shield is configured to hide the electrode 22 when viewed from the inside of the plasma generation chamber 17, there is a dielectric surface on which negative DC self-bias is applied in the ion traveling direction. The ion bombardment to the inner wall of the process tube 7 is suppressed. Therefore, the inner wall of the process tube 7 is less likely to be sputtered by ions, and the amount of sputtering in the plasma generation chamber can be reliably reduced.
In particular, if the connection portion 30 connecting the pieces 23a is arranged so as to overlap with the electrode 22 as much as possible, and the loop-shaped electrode 22 is also hidden by the connection portion 30, the amount of spatter in the plasma generation chamber 17 can be further increased. It can certainly be reduced.

  Since the sputtering of the inner wall of the plasma generation chamber 17 can be effectively suppressed in this way, particles falling on the wafer 6 can be greatly reduced.

  Further, an eddy current flows through the shield 23 due to the magnetic field generated from the electrode 22. Therefore, the shield 23 is preferably formed of a conductor having a low resistance value, such as Al or Cu. Moreover, since the eddy current flowing through the shield 23 is a loss of high-frequency power input to the electrode 22, it is necessary to reduce it as much as possible. In this respect, in the present embodiment, a single planar shield is subdivided into a plurality of pieces 23a, these pieces 23a are connected, and the shield 23 is integrally formed. Reducing losses. In this sense, the shield 23 is not limited to the shape in the illustrated example, and may have any shape as long as it can block the electric field and suppress the generation of eddy currents.

  In this embodiment, since the electrode 22 is installed outside the process tube 7 and the electrode protection tube can be omitted, the process tube 7 can be compared with the conventional method in which the electrode is installed inside the process tube 7. Can be simplified, and the manufacturing cost can be reduced.

  In addition, according to the semiconductor manufacturing apparatus of the present embodiment, the second gas (processing gas) is activated in the immediate vicinity of the wafer 6 by the EBEP method. It is possible to supply the required amount. Further, since the wafer 6 is not exposed to high energy plasma generated by capacitively coupled plasma (CCP) or the like, the wafer 6 itself is not damaged by the plasma.

  Furthermore, in the plasma generation chamber 17, it is sufficient to generate plasma only for extracting electrons, so it is not necessary to apply high-output high-frequency power, and the quartz wall constituting the process tube 7 can be sputtered. The nature is low.

  Further, in this embodiment, an ICP plasma source is used in the plasma generation chamber, and the ICP plasma source is outside the process tube 7, so that compared with the case of using a filament (ultra-high temperature metal), the processing is performed. It is not a source of pollution and is very clean.

  In addition, since the plasma is uniformly formed on each wafer 6, when the plasma processing is a film forming process, the film quality is greatly improved, and the product throughput is also improved by being a batch type. .

  In addition, the plasma generation chamber 17 is provided in the vertical direction along the side surface of the boat 3 to uniformly generate the plasma 18 serving as an electron source of the EBEP method in the vertical direction. Since the gas supplied between the wafers 6 is directly plasma-excited by being fired between the plurality of wafers 6 in the processing chamber 29, it is possible to improve the film thickness uniformity within the wafer surface and between the wafers. it can.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be appropriately modified and implemented.

  For example, the plasma generation method in the plasma generation chamber 17 uses an ICP plasma source by applying a high frequency as an example in the above embodiment, but is not limited to this. Other methods can be applied as long as the plasma generation method suppresses the sputtering effect as much as possible, such as wave plasma.

The semiconductor manufacturing apparatus according to the present invention is applied when removing foreign matters (molecules or atoms other than the film type) intervening in the film type, when forming a CVD film on the wafer, when diffusing, or when performing heat treatment. can do. In this case, the plasma gas in the plasma generation chamber 17 and the plasma gas 28 contributing to the reaction for wafer processing may be the same or different. In the case of being different, a gas supply pipe (not shown) different from the gas supply pipe 31 is required. Note that hydrogen (H ₂ ), helium (He), argon (Ar), nitrogen (N ₂ ), ammonia (NH ₃ ), nitrogen monoxide (N ₂ O), or the like can be used as the plasma gas. .

For example, in the process of nitriding an oxide film for a gate electrode of a DRAM, the processing chamber 29 is heated to room temperature to 750 ° C., and nitrogen (N ₂ ) gas, ammonia (NH ₃ ), or nitrogen monoxide is supplied from the gas supply pipe 31. The surface of the oxide film can be nitrided by supplying (N ₂ O) into the plasma generation chamber 17 and generating nitrogen plasma between the wafers 6 in the processing chamber 29. Further, by supplying hydrogen (H ₂ ) gas from the gas supply pipe 31 into the plasma generation chamber 17 and generating hydrogen plasma between the wafers 6 in the processing chamber 29, a silicon germanium (SiGe) film is formed. By removing the natural oxide film from the surface of the previous silicon wafer, a desired SiGe film can be formed. In forming a nitrogen film at a low temperature, ALD (Atomic Layer Deposition) in which DCS (dichlorosilane) and NH ₃ (ammonia) are alternately supplied to form Si (silicon) and N (nitrogen) one by one. when performing atomic layer deposition), when the supply of NH _3, to supply NH ₃ from the gas supply pipe 31, by generating the ammonia plasma between the wafer 6, it is possible to obtain a high-quality nitride film.

  Hereinafter, preferred embodiments of the present invention will be additionally described.

A first aspect includes a processing container that processes a plurality of substrates, a substrate holder that is accommodated in the processing container and holds the plurality of substrates in multiple stages, and a plasma generation chamber provided on a side surface of the substrate holder A first gas supply unit that supplies a first gas into the plasma generation chamber, and a second gas supply unit that supplies a second gas between the plurality of substrates held by the substrate holder An electrode that is provided outside the processing vessel and that excites the first gas supplied into the plasma generation chamber by inductive coupling to generate plasma, and is grounded between the electrode and the plasma generation chamber. Provided between the plurality of substrates in the processing vessel and supplied between the substrates. The shield is provided in the plasma generation chamber and emits electrons among the plasma generated in the plasma generation chamber. Said second gas A semiconductor manufacturing apparatus and an electronic supply device for plasma excitation.
Since the shield is provided between the electrode and the plasma generation chamber while being grounded, it is possible to reduce the occurrence of sputtering due to ion collision on the wall of the plasma generation chamber, and to reliably suppress the generation of particles.

  A second aspect is the semiconductor manufacturing apparatus according to the first aspect, wherein the shield has a shape that hides the electrode when viewed from the inside of the plasma generation chamber. When the shield has a shape that hides the electrode when viewed from the inside of the plasma generation chamber, it is possible to further reduce the occurrence of sputtering due to ion collision on the plasma generation chamber wall, and to more reliably suppress the generation of particles.

  A third aspect is the semiconductor manufacturing apparatus according to the first and second aspects, wherein the plasma generation chamber is provided on a part of the inner wall of the processing vessel. The plasma generation chamber may be provided adjacent to a part of the outside of the processing container, or may be provided adjacent to a part of the inner wall of the processing container. When the plasma generation chamber is provided on a part of the inner wall of the processing vessel, the distance between the particle generation source and the substrate is close, so in particular, the adhesion of particles to the substrate becomes a problem, but a ground shield is provided. It is possible to solve such problems.

  A fourth aspect is a semiconductor manufacturing apparatus according to any one of the first to third aspects, in which the shield is integrally formed by connecting a plurality of subdivided pieces. By making the shield into pieces, the loss of high-frequency power due to the eddy current generated in the shield can be reduced.

  A fifth aspect is a semiconductor manufacturing apparatus according to the fourth aspect, wherein the connection part connecting the plurality of pieces is arranged so as to overlap the electrode, and the electrode is also hidden by the connection part. According to this, the amount of sputtering in the plasma generation chamber can be more reliably reduced.

It is a longitudinal cross-sectional view which shows the structure of the heat processing furnace of the semiconductor manufacturing apparatus in one embodiment of this invention. It is a Y arrow line view in FIG. It is XX sectional drawing in FIG. It is a figure explaining the electron beam excitation plasma in one embodiment of this invention. 1 is an overall perspective view of a semiconductor manufacturing apparatus according to an embodiment of the present invention. It is a longitudinal cross-sectional view of the heat processing furnace in the semiconductor manufacturing apparatus of a prior art example. It is the XX sectional view taken on the line in FIG. It is explanatory drawing of the plasma source of the heat processing furnace in the semiconductor manufacturing apparatus of a prior art example.

Explanation of symbols

3 boat (substrate holder)
6 Wafer (substrate)
7 Process chamber
17 Plasma generation chamber 18 Plasma 41 Electron gun (electron supply device)
22 Electrode 23 Shield 31 Gas supply pipe (first gas supply part)

Claims (1)

A processing container for processing a plurality of substrates;
A substrate holder that is housed in the processing container and holds the plurality of substrates in multiple stages;
A plasma generation chamber provided on a side surface of the substrate holder;
A first gas supply unit for supplying a first gas into the plasma generation chamber;
A second gas supply unit for supplying a second gas between the plurality of substrates held by the substrate holder;
An electrode that is provided outside the processing vessel and generates plasma by exciting the first gas supplied into the plasma generation chamber by inductive coupling;
A shield provided to be grounded between the electrode and the plasma generation chamber;
The second gas that is provided in the plasma generation chamber, emits electrons among the plasma generated in the plasma generation chamber between the plurality of substrates in the processing container, and is supplied between the substrates. A semiconductor manufacturing apparatus comprising an electron supply device that excites plasma.