JP2006049367A - Plasma processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma processing apparatus which can realize uniform plasma processes and control generation of particles. <P>SOLUTION: The plasma processing apparatus processes a substrate 5 to be processed placed within an evacuated processing chamber 1. In this plasma processing apparatus, a plurality of AC power application electrode plates 3, 4 are provided so as to hold the substrate 5 and not to be in contact with the substrate 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a plasma processing apparatus, and more particularly, to a plasma processing apparatus that etches the surface of a substrate such as a silicon wafer using plasma, forms a thin film, or modifies the surface.

  FIG. 8 is a schematic partially cutaway perspective view for explaining a processing furnace of a conventional batch type plasma processing apparatus that collectively processes a plurality of substrates to be processed with plasma, and FIG. 9 is a conventional batch type. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of a plasma processing apparatus.

  The processing chamber 1 is hermetically configured by the reaction tube 2 and the seal cap 25, and a heater 14 is provided around the reaction tube 2 so as to surround the processing chamber 1. The reaction tube 2 is made of a dielectric material such as quartz.

  Inside the processing chamber 1, a susceptor electrode A23 and a susceptor electrode B24 made of a conductive material are attached to the conductive electrode support A21 and the electrode support B20, respectively, so as to alternately overlap in multiple stages. The two electrode columns 20 and 21 pass through the seal cap 25 of the processing chamber 1 to the outside while being insulated from the seal cap 25 by an insulating member (not shown), and the AC power output from the oscillator 8 is passed through the matching unit 9. It can be applied.

  The processing chamber 1 is connected to a pump 7 through an exhaust pipe 6 so that the gas inside the processing chamber 1 can be exhausted.

  Further, a gas introduction port 10 is provided in the processing chamber 1 so that a gas necessary for processing a substrate to be processed can be introduced into the processing chamber 1 for processing.

  An alternating electric field is generated between the susceptor electrodes A23 and B24 in the processing chamber 1, and the gas introduced from the gas introduction port 10 is turned into plasma to process the substrate 5 to be processed placed on the susceptor electrodes A23 and B34.

  Next, the operation of this apparatus will be described.

  When the processing chamber 1 is at atmospheric pressure, a seal cap 25 on which a susceptor electrode for loading a substrate 5 to be processed is loaded by an elevator mechanism (not shown) is lowered, and a substrate support pin (not shown) for conveying a substrate to be processed (not shown). After the required number of substrates to be processed 5 are placed on the susceptor electrode A23 and the susceptor electrode B24 by the cooperative operation of the robot, the seal cap 25 is raised and inserted into the processing chamber 1.

  The number of susceptor electrodes on which the substrate 5 to be processed is placed is determined by the restrictions on the distance between the susceptor electrodes A23 and B24 determined by the plasma generation conditions and the size of the processing chamber 1 in the height direction.

  Electric power is applied to the heater 14 to heat the members inside the processing chamber 1 such as the substrate 5 to be processed, the reaction tube 2, and the susceptor electrodes A23 and B24 to a predetermined temperature.

  If the temperature of the heater 14 is excessively lowered during the transfer of the substrate 5 to be processed, a considerable amount of time is required to raise the temperature to a predetermined value within the processing chamber 1 and stabilize it after the transfer of the substrate 5 to be processed. Therefore, normally, the temperature of the substrate to be processed 5 is lowered to a temperature that does not hinder the transfer, and the substrate 5 is transported while being held at that value.

  At the same time, the gas inside the reaction tube 2 is exhausted by a pump 7 through an exhaust pipe 6 from an exhaust port (not shown).

  When the substrate 5 to be processed reaches a predetermined temperature, a reactive gas is introduced into the processing chamber 1 from the gas introduction port 10 and the pressure in the processing chamber 1 is maintained at a predetermined value by a pressure adjusting mechanism (not shown).

  When the pressure inside the processing chamber 1 reaches a predetermined pressure, AC power output from the oscillator 8 is supplied to the electrode strut A21 and the electrode strut B20 via the matching unit 9, and plasma is generated between the susceptor electrodes A23 and B24. To do.

  As the frequency of the AC power supplied to the electrode column A21 and the electrode column B20, a high frequency of 13.56 MHz or a low frequency of about 400 KHz is used.

When low frequency power of 400 KHz is used, ions in the plasma are accelerated by a low frequency AC electric field between the susceptor electrodes A23 and B24, and ion bombardment in the plasma can be given to the surface of the substrate 5 to be processed.
This function is effective when performing plasma etching or nitriding of the oxide film surface.
In the example of the prior art, the seal cap 25 can be used as a ground electrode, but a ground electrode may be provided at other locations inside the processing chamber 1.

  Problems of the prior art will be described with reference to FIGS.

  First, referring to FIGS. 10 to 12, the processing characteristics of the substrate 5 to be processed placed on the susceptor electrodes 23 and 24, which is known as the edge effect, change in the peripheral portion of the substrate 5 to be processed. The phenomenon will be described.

  This phenomenon is caused by a change in physical shape and material at the edges of the susceptor electrodes 23 and 24 and the substrate 5 to be processed, resulting in non-uniform gas flow, non-uniform pressure, and non-uniform plasma parameters. This occurs because the degree of action during processing of the substrate to be processed changes.

  In particular, in the generation of plasma that greatly affects the processing of the substrate 5 to be processed, the electric field concentrates on the edge portions around the susceptor electrodes 23 and 24, thereby avoiding the influence of the substrate 5 on the susceptor electrodes 23 and 24. It is a difficult phenomenon to do.

  The shape of the edge portion is such that the diameter of the substrate 5 to be processed is smaller than the diameter of the susceptor electrodes 23 and 24 as shown in FIG. 10, the diameter is the same as shown in FIG. 11, the susceptor electrode 23 as shown in FIG. Although the case where the diameter of 24 is smaller than the diameter of the substrate 5 to be processed can be considered, in any case, the plasma generation around the substrate to be processed is affected, which causes uneven processing.

Further, the substrate to be processed 5 may be warped or deformed by the action of heat or the action of the stress of the thin film on the surface.
For this reason, as shown in FIG. 13, a gap is generated between the substrate to be processed 5 and the susceptor electrodes 23 and 24, and causes of non-uniform processing of the substrate to be processed 5 on the susceptor electrodes 23 and 24 stacked in multiple stages. It becomes.

  Depending on the gap between the susceptor electrodes 23 and 24 and the substrate 5 to be processed, for example, when film formation is involved during processing, the surface of the substrate 5 to be processed reacts in a patchy manner as shown in FIG. Since a thin film made of the product 13 is generated, a non-uniform gap 39 exists between the substrate to be processed 5 and the susceptor electrodes 23 and 24 as shown in FIG. 15 when the substrate to be processed 5 is placed. It becomes a state.

  In particular, when the thin film made of the reaction product 13 generated in a spot shape is insulative, if the plasma treatment is performed in such a state, the amount of charge flowing from the plasma to the susceptor electrodes 23 and 24 through the substrate to be treated 5 is non-uniform. become.

  As a result, the charge concentration distribution in the substrate 5 to be processed becomes non-uniform, and the action of ions between the plasma and the surface of the substrate to be processed becomes non-uniform so that the processing of the non-processed substrate 5 becomes non-uniform. is there.

  Further, as shown in FIG. 16, in order to place the substrate 5 to be processed on the susceptor electrodes 23, 24, the pins 16 inserted from below the multi-stage susceptor electrodes 24, 24 and the tweezers 15 work together. However, it is necessary to provide the susceptor electrodes 23 and 24 with holes 26 through which the pins 16 pass.

FIG. 17 shows a state in which the substrate to be processed 5 is received by the pins 16, but when a thin film is formed during processing of the substrate to be processed 5, reactive gas is generated from the back side of the susceptor electrodes 23 and 24. The reaction product 13 is deposited around the hole 26. When the substrate 5 is transported, it comes into contact with the pins 16 and generates particles 17.
When the particles 17 are placed on the substrate 5 to be processed, the processing yield of the substrate 5 to be processed is lowered.
Therefore, a structure in which the hole 26 is not provided in the susceptor electrode is desired.

As described above, the prior art has the following problems.
(1) The processing of the substrate to be processed becomes non-uniform due to the interaction between the susceptor electrode and the edge portion of the substrate to be processed.
(2) The gap between the susceptor electrodes caused by warpage or distortion of the substrate to be processed changes the state of charges incident from the plasma through the substrate to be processed, which causes processing non-uniformity.
(3) Similarly, even when a normal target substrate with small warpage is placed on the susceptor electrode due to variations in the distribution of thin films deposited in the gaps between the susceptor electrodes caused by warpage or distortion of the target substrate, The state of charge incident from the plasma through the substrate to be processed changes, and this causes non-uniform processing.
(4) Reaction by-products are deposited in holes for penetrating the pins used for transporting the substrate to be processed provided in the susceptor electrode, and are peeled off to form particles, thereby reducing the processing yield of the substrate to be processed.

  Accordingly, a main object of the present invention is to provide a plasma processing apparatus capable of performing uniform plasma processing and suppressing generation of particles.

According to the present invention,
A plasma processing apparatus for processing a substrate to be processed placed in a processing chamber under reduced pressure using plasma, for applying a plurality of alternating current power so as to sandwich the substrate to be processed and not to contact the substrate to be processed A plasma processing apparatus provided with an electrode plate is provided.

  Preferably, a plurality of substrates to be processed are placed in the processing chamber, the plurality of substrates to be processed are collectively processed using plasma, and are in contact with the substrates to be processed so as to sandwich the plurality of substrates to be processed, respectively. A plurality of alternating-current power application electrode plates are provided so as not to occur.

  Preferably, the plurality of AC power applying electrode plates are electrode plates for controlling the energy of ions incident on the substrate to be processed.

  Preferably, AC power that is 180 degrees out of phase is applied to the adjacent AC power application electrode plates. In this way, the AC applied voltage can be increased.

  Preferably, in order to generate plasma in the processing chamber, an AC power application electrode different from the AC power application electrode plate installed so as to sandwich the substrate to be processed is provided outside or inside the processing chamber. Provided.

  Preferably, the second AC power application electrode for generating the plasma is insulated from the oscillator by an insulating transformer.

  Preferably, the AC power applying electrode plate placed so as to sandwich the substrate to be processed is insulated from the oscillator by an insulating transformer.

  Preferably, the frequency of the AC power applied to the AC power application electrode plate provided so as to sandwich the substrate to be processed is 1 MHz or less.

  Preferably, the plurality of AC power applying electrode plates installed so as to sandwich the substrate to be processed are divided into two groups, and one of the two groups is an electrode plate of the other group. The outputs from the two oscillators are respectively applied to the one group of electrode plates and the other group of electrode plates to control the phase difference between the two oscillators.

  Preferably, the plurality of AC power applying electrode plates installed so as to sandwich the substrate to be processed are divided into two groups, and one of the two groups of electrode plates is the other group. While being alternately arranged with the electrode plates, the outputs from the two oscillators are respectively applied to the one group of electrode plates and the other group of electrode plates, and the substrate is subjected to plasma treatment. The phase difference can be controlled to change at a constant speed.

  Preferably, the plurality of AC power application electrode plates are provided in the processing chamber, and the processing chamber includes a fixed processing chamber forming member and a movable processing chamber forming member. The electrode plate is movably provided together with the movable processing chamber forming member, and is movable when the processing chamber is hermetically configured by the movable processing chamber forming member and the fixed processing chamber forming member. AC power can be applied from the fixed processing chamber forming member to the plurality of AC power applying electrode plates via the processing chamber forming member.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to perform uniform plasma processing, the plasma processing apparatus which can suppress generation | occurrence | production of a particle is provided.

  In a preferred embodiment of the present invention, the substrate to be processed is not placed on the susceptor electrode, and the non-processed substrate is held on a dedicated boat so as to support the edge portion.

In addition, in order to use the impact of plasma ions or supply sufficient plasma to the surface of the substrate to be processed, an AC power application electrode is provided so as to sandwich the substrate to be processed and not to contact it.
Next, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic partially cutaway perspective view for explaining the processing furnace of the batch type plasma processing apparatus of the first embodiment, and FIG. 2 shows the processing furnace of the batch type plasma processing apparatus of the first embodiment. FIG. 3 is a partially enlarged schematic longitudinal sectional view for explaining the processing furnace of the batch type plasma processing apparatus of the first embodiment.

  The processing chamber 1 is hermetically configured by the reaction tube 2 and the seal cap 25, and a heater 14 is provided around the reaction tube 2 so as to surround the processing chamber 1. The reaction tube 2 is made of a dielectric material such as quartz.

  In the processing chamber 1, the conductive electrode columns A 21 and the electrode columns are formed at equal intervals so that the electrodes A 3 and the electrodes B 4 made of a conductive material are alternately stacked in multiple stages and do not contact the substrate 5 to be processed. Each is attached to B20. The two electrode struts A21 and B20 pass through the outside of the processing chamber 1 while being insulated from the seal cap by an insulating member (see FIG. 3), and can apply the AC power output from the oscillator 8 through the matching unit 9. It is like that.

The frequency of the AC power is selected depending on the processing method of the substrate 5 to be processed. When ions in plasma collide with the surface of the substrate 5 to be processed and the collision energy is used, a low frequency is used. Usually 1 MHz or less, but preferably around 400 KHz.
In the case of processing that does not actively use ion bombardment on the surface of the substrate 5 to be processed, a high frequency such as 13.56 MHz is used.

  The processing chamber 1 is connected to a pump 7 through an exhaust pipe 6 so that the gas inside the processing chamber 1 can be exhausted.

  Further, a gas introduction port 10 is provided in the processing chamber 1 so that a necessary gas can be introduced into the processing chamber 1 for processing.

  Between the electrode A3 and the electrode B4 in the processing chamber 1, the gas introduced from the gas introduction port 10 is turned into plasma by the alternating electric field generated by the application of alternating current power, and the substrate 5 placed on the susceptor electrode is processed. It has a structure to do.

  A ring-shaped auxiliary electrode A18 and auxiliary electrode B19 for generating plasma in the processing chamber 1 are provided outside the reaction tube 2 so that AC power output from the oscillator 11 can be supplied via the matching unit 12. It has become.

  The frequency of the AC power supplied to the auxiliary electrodes A18 and B19 is a high frequency such as 13.56 MHz, and the auxiliary electrodes A18 and B19 are used to generate plasma throughout the processing chamber 1.

  When processing the substrate 5 to be processed, plasma is generated by the auxiliary electrodes A18 and B19, and low frequency power of about 400 KHz is supplied to the electrodes A3 and B4 installed so as to sandwich the substrate 5 to be processed in the processing chamber 1. The low-frequency AC voltage applied between the electrodes A3 and B4 is held at a constant value. The value of the low-frequency AC voltage is appropriately selected depending on how the substrate 5 is processed.

The material of the auxiliary electrodes A18 and B19 may be a normal metal with good conductivity when the processing temperature is as low as about 400 ° C., but a refractory metal or SiC (silicon carbide) is used at a high temperature.
The atmosphere of the auxiliary electrodes A18 and B19 is preferably filled with a gas not containing oxygen, such as nitrogen, in order to prevent oxidation and deterioration.
The auxiliary electrodes A18 and B19 may be provided inside the processing chamber 1. In that case, a high-purity conductive material, for example, SiC (silicon carbide) is used in consideration of contamination of the substrate 5 to be processed.

  The boat 22 is provided with a groove for placing the peripheral portion of the substrate to be processed 5 so that the substrate to be processed 5 can be placed on the boat 22 at equal intervals. The wafer transfer machine 112) can automatically transfer the substrate 5 to be processed. In this embodiment, a semiconductor silicon wafer is used as the substrate 5 to be processed.

  When transporting the substrate to be processed 5, a tweezer (not shown) for placing the substrate to be processed of the robot for transporting the substrate to be processed is inserted between the electrodes A 3 and B 4, and the substrate 5 to be processed is directly placed in a groove provided in the boat 22. Therefore, unlike the case of transporting onto the susceptor electrode, a pin for temporarily supporting the substrate to be processed 5 is not necessary. For this reason, the electrodes A and B do not need to be provided with holes for penetrating the pins.

  The boat 22 is usually made of a dielectric such as quartz or ceramics.

  The to-be-processed substrate 5, electrode A3, and electrode B4 are arrange | positioned so that it may not contact, This structure differs from a prior art. Since the substrate 5 to be processed is separated from the electrode A3 and the electrode B4, the non-uniformity of the plasma generated by the electrodes A3 and B4 or the plasma generated by the auxiliary electrodes A18 and B19 and adjusted by the electrodes A3 and B4 is covered. The influence on the processing of the peripheral portion of the processing substrate 5 can be suppressed. Since the substrate 5 to be processed and the electrode A3 and the electrode B4 are arranged so as not to contact with each other, it is necessary to process a hole for a pin required when the substrate 5 to be processed is transferred to the electrode A3 and the electrode B4. The structure can be greatly simplified. Moreover, it can suppress that the reaction by-product accumulated in the hole for pins peels off, adheres to the to-be-processed substrate 5, and reduces a yield.

  Further, since the substrate 5 to be processed and the electrodes A3 and B4 are separated from each other, the growth of the thin film deposited on the surfaces of the electrodes A3 and B4 during the processing of the substrate 5 to be processed is uniform in each of the electrodes A3 and B4. In addition, non-uniform plasma generation can be suppressed.

The electrode column A21, the electrode column B20, and the electrode A3 and the electrode B4 that are installed at equal intervals so as to overlap each other in parallel are made of a conductive material.
In the case of low temperature or when applied to a process where contamination is not a problem, a normal metal for aluminum or stainless steel may be used. In the case of a high-temperature process in which metal contamination becomes a problem, SiC (silicon carbide), carbon, or a material obtained by coating SiC on carbon is used. A material obtained by spraying a dielectric material such as ceramics on a normal metal may be used.

  The distances between the electrodes A3 and B4 and the substrate to be processed 5 are appropriately adjusted depending on how plasma is generated when the substrate to be processed 5 is processed.

  The electrode A3 and the electrode B4 that are attached at equal intervals so as to overlap the electrode column A21 and the electrode column B20 are equally spaced, and are similarly the same as the interval of the substrate 5 to be processed placed on the boat 22. It is.

When the distance between the electrode A3 and the electrode B4 is not changed but the positional relationship with the substrate 5 is matched, the electrode support A21 and the electrode support B20 are moved up and down collectively. Since the vertical mechanism may be normally fixed, a conductive spacer may be set and adjusted in the lower part of each of the electrode support A21 and the electrode support B20.
It is also effective to automatically move the electrode strut A21 and electrode strut B20 up and down in order to change the plasma generation conditions during one treatment.

  The interval between the substrates to be processed 5 placed on the boat 22 is appropriately determined depending on the method of processing, and is determined in consideration of, for example, process pressure, gas flow, plasma parameter (density and electron temperature) distribution, and the like.

  As shown in FIG. 3, AC power is supplied to the electrode A3 by providing a ring-shaped reaction tube ring 27 between the reaction tube 2 and the seal cap 25 in an airtight manner, and an upper insulator 28 is provided inside the reaction tube ring 27. A simple structure can be achieved by supplying the electrode post A20 through the lower feeder 30 insulated by the upper feeder 31 and the lower insulator 29 provided in the seal cap 25. The method for supplying AC power is the same for the electrode B4. If this mechanism is used, a feeder that supplies AC power can be fixed, and thus reliability can be improved.

  Next, the operation of this apparatus will be described.

  The boat 22 and the seal cap 25 on which the electrode A3 and the electrode B4 are loaded are loaded by using the elevator mechanism (see the elevating member 122 in FIGS. 6 and 7) while the processing chamber 1 is at atmospheric pressure. Then, after a desired number of substrates to be processed 5 are mounted on the boat 22 by a substrate transfer robot (see the wafer transfer machine 112 in FIGS. 6 and 7), the seal cap 25 is raised to raise the inside of the processing chamber 1. Insert into.

  The number of electrodes A3 and B4 is determined by the constraints on the distance between the electrodes A3 and B4 determined by the conditions for generating plasma and the size of the processing chamber 1 in the height direction.

  Electric power is supplied to the heater 14 to heat the members in the processing chamber 1 such as the substrate 5 to be processed, the reaction tube 2, the electrode A3, and the electrode B4 to a predetermined temperature.

  If the temperature of the heater 14 is excessively lowered during the transfer of the substrate 5 to be processed, a considerable amount of time is required to raise the temperature to a predetermined value within the processing chamber 1 and stabilize it after the transfer of the substrate 5 to be processed. Therefore, normally, the temperature of the substrate to be processed 5 is lowered to a temperature that does not hinder the transfer, and the substrate 5 is transferred while being held at that value.

  At the same time, the gas inside the reaction tube 2 is exhausted by a pump 7 through an exhaust pipe 6 from an exhaust port (not shown).

  When the substrate 5 to be processed reaches a predetermined temperature, a reactive gas is introduced into the processing chamber 1 from the gas introduction port 10 and the pressure in the processing chamber 1 is maintained at a predetermined value by a pressure adjusting mechanism (not shown).

  When the pressure inside the processing chamber 1 reaches a predetermined pressure, the high-frequency power output from the oscillator B11 is supplied to the auxiliary electrode A18 and the auxiliary electrode 19B via the matching unit B12 to generate plasma in the processing chamber 1.

  At the same time, the low-frequency power output from the oscillator 8 is supplied to the electrode column A21 and the electrode column B20 via the matching unit 9, and is incident on the surface of the substrate 5 to be processed by the low-frequency AC voltage generated between the electrodes A3 and B4. The to-be-processed substrate 5 installed in the boat 22 is processed while controlling the energy of ions.

Here, there are several methods for generating plasma.
(First method)
Plasma is generated by supplying high frequency power of 13.56 MHz output from the oscillator B11 to the auxiliary electrode A18 and the auxiliary electrode B19 via the matching unit B12. At the same time, the low frequency power of 400 MHz output from the oscillator 8 is supplied to the electrode column A21 and the electrode column B20 via the matching unit 9 so that the low frequency voltage between the electrode A3 and the electrode B4 becomes a constant value.

Thereby, the collision energy of ionized particles of the reactive gas incident on the surface of the substrate 5 to be processed can be controlled. The surface of the substrate 5 to be processed is processed according to the purpose by controlling the low-frequency AC voltage.
For example, when nitriding an oxide film surface on a silicon wafer, nitrogen plasma is used. Nitriding by nitrogen plasma on the oxide film surface determines the nitrogen concentration on the surface depending on the energy of nitrogen ions in the plasma. Therefore, the nitrogen concentration can be controlled by controlling the low-frequency voltage between the electrodes A3 and B4. it can.

(Second method)
There is a method in which an auxiliary electrode is not used and low-frequency power is applied between the electrodes A3 and B4 provided so as to sandwich the substrate 5 to be processed, thereby simultaneously controlling plasma generation and energy of ions incident on the substrate 5 to be processed.
Compared to the first method, the plasma generation state and the ion energy incident on the substrate 5 to be processed change at the same time, so that the controllability of the processing is deteriorated.

FIG. 4 is a schematic longitudinal sectional view for explaining the processing furnace of the batch type plasma processing apparatus of the second embodiment. In this embodiment, the auxiliary electrode A18, the auxiliary electrode B19, the electrode A3, and the electrode B4 are insulated by the insulating transformer B33 and the insulating transformer A32, respectively, and the leakage of AC power to the heater 14 and the like is suppressed. 1 is different, but the other points are the same. By providing the isolation transformers A32 and B33, mutual interference with the oscillators 8 and 11 can be prevented, respectively.
Further, since low frequency power having a phase difference of 180 degrees is applied between the electrode A3 and the electrode B4, the voltage between the electrodes is increased, and the substrate 5 to be processed can be processed efficiently.

  FIG. 5 is a schematic longitudinal sectional view for explaining the processing furnace of the batch type plasma processing apparatus of the third embodiment. In this embodiment, the oscillator C34 and the matching unit C35 are connected to the electrode A3, the oscillator D36 and the matching unit D37 are connected to the electrode B4, and the two oscillators C34 and D36 are connected to the phase shifter 38 to generate plasma. Although the plasma generation state is changed by changing the phase difference between the two oscillators C34 and D36 at a constant speed while processing the substrate 5 to be processed, The point is the same. Thereby, the uniformity of the processing state of the substrate 5 to be processed can be changed.

  The oscillator C34 and the matching unit C35 are connected to the electrode A3, and the oscillator D36 and the matching unit D37 are connected to the electrode B4, thereby generating plasma and processing the substrate 5 to be processed without providing the phase shifter 38. During this time, the phase difference between the two oscillators C34 and D36 can be controlled.

  As described above, according to the preferred embodiment of the present invention, since the substrate to be processed and the electrode are arranged apart from each other, when processing with plasma, the plasma state is not uniform as seen in the periphery of the susceptor electrode. The influence of the property on the substrate to be processed can be suppressed.

  In addition, since the electrodes provided so as to sandwich the substrate to be processed are not in contact with the substrate 5 to be processed, it is possible to suppress non-uniform gas flow, non-uniform pressure, non-uniform plasma parameters, and adverse temperature effects. it can.

  Further, the substrate 5 to be processed may be warped or deformed due to the action of heat or the stress of the thin film on the surface, but since it is separated from the electrode, unstable charges between the substrate 5 to be processed and the electrode. Therefore, uniform processing is possible.

  Furthermore, since the substrate to be processed 5 is transported completely independently of the electrodes, pins that temporarily support the substrate to be processed are not required during the transport, and holes that penetrate the electrodes are not necessary. Thereby, there is no fear of deposition of reaction by-products in the holes provided in the electrodes, and the adhesion of particles to the substrate to be processed is remarkably suppressed and the yield is improved.

  Next, an outline of the substrate processing apparatuses according to the first to third embodiments will be described with reference to FIGS.

  A cassette stage 105 is provided on the front side of the inside of the housing 101 as a holder transfer member that transfers 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 lifting 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 processing furnace 202 is provided above the rear portion of the casing 101, and a boat 22 as a substrate holding unit that holds the wafers 5 as substrates in a multi-stage in a horizontal posture is raised and lowered to the processing furnace 202 below the processing furnace 202. A boat elevator 121 as an elevating means is provided, and a seal cap 25 as a lid is attached to the tip of an elevating member 122 attached to the boat elevator 121 to support the boat 22 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 is provided as a closing unit that has an opening / closing mechanism and hermetically closes the wafer loading / unloading port 131 below the processing furnace 202.

  The cassette 100 loaded with the wafer 5 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 5 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 on which the wafer 5 is transferred 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 wafer 5 is transferred from the transfer shelf 123 to the lowered boat 22 by the cooperation of the advance / retreat 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 5 are transferred to the boat 22, the boat 22 is inserted into the processing furnace 202 by the boat elevator 121, and the processing furnace 202 is hermetically closed by the seal cap 25. The wafer 5 is heated in the hermetically closed processing furnace 202 and a processing gas is supplied into the processing furnace 202 to process the wafer 5.

  When the processing on the wafer 5 is completed, the wafer 5 is transferred from the boat 22 to the cassette 100 of the transfer shelf 123 by the reverse procedure of the operation described above, 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 processing furnace 202 when the boat 22 is in the lowered state, and prevents outside air from being caught in the processing furnace 202.

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

BRIEF DESCRIPTION OF THE DRAWINGS It is a general | schematic partially notched perspective view for demonstrating the processing furnace of the batch type plasma processing apparatus of Example 1 of this invention. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the batch type plasma processing apparatus of Example 1 of this invention. It is a partial expanded schematic longitudinal cross-sectional view for demonstrating the processing furnace of the batch type plasma processing apparatus of Example 1 of this invention. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the batch type plasma processing apparatus of Example 2 of this invention. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the batch type plasma processing apparatus of Example 3 of this invention. It is a schematic oblique view for demonstrating the batch type plasma processing apparatus of Example 1 thru | or 3 of this invention. It is a schematic longitudinal cross-sectional view for demonstrating the batch type plasma processing apparatus of Example 1 thru | or 3 of this invention. It is a general | schematic partially notched perspective view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus. It is a schematic longitudinal cross-sectional view for demonstrating the processing furnace of the conventional batch type plasma processing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Processing chamber 2 ... Reaction tube 3 ... Electrode A
4 ... Electrode B
5 ... Wafer 6 ... Exhaust pipe 7 ... Pump 8 ... Oscillator A
9 ... Matching device A
10 ... Gas introduction port 11 ... Oscillator B
12 ... Matching device B
13 ... Reaction product 14 ... Heater 15 ... Tweezer 16 ... Pin 17 ... Particle 18 ... Auxiliary electrode A
19 ... Auxiliary electrode B
20 ... Electrode support B
21 ... Electrode support A
22 ... boat 23 ... susceptor electrode A
24. Susceptor electrode B
25 ... Seal cap 26 ... Hole 27 ... Reaction tube ring 28 ... Upper insulator 29 ... Lower insulator 30 ... Lower feeder 31 ... Upper feeder 32 ... Insulation transformer A
33. Insulation transformer B
34. Oscillator C
35 ... Matching device C
36 ... Oscillator D
37 ... Matching device D
38 ... Phase shifter 39 ... Gap
DESCRIPTION OF SYMBOLS 100 ... Cassette 101 ... Case 105 ... Cassette stage 109 ... Cassette shelf 110 ... Reserve cassette shelf 112 ... Wafer transfer machine 113 ... Transfer elevator 114 ... Cassette transfer machine 115 ... Cassette elevator 116 ... Furnace shutter 118 ... Clean unit DESCRIPTION OF SYMBOLS 121 ... Boat elevator 122 ... Elevating member 123 ... Transfer shelf 124 ... Conveyance control means 202 ... Processing furnace

Claims (1)

A plasma processing apparatus for processing a substrate to be processed placed in a processing chamber under reduced pressure using plasma, for applying a plurality of alternating current power so as to sandwich the substrate to be processed and not to contact the substrate to be processed A plasma processing apparatus provided with an electrode plate.

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