JP4281986B2 - Substrate processing equipment - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a batch-type substrate processing apparatus for processing a plurality of substrates in a reaction tube used in one step of a semiconductor device manufacturing process, and more particularly to a gas supply structure for supplying gas to a plurality of substrates.
[0002]
[Prior art]
The prior art will be described with reference to FIGS.
1, 2, and 3 show examples of the configuration of a conventional remote plasma type substrate processing apparatus provided with electrodes inside a reaction tube, and FIGS. 4, 5, and 6 show other reaction chambers of the remote plasma processing apparatus. FIG. 7 and FIG. 8 show a configuration example of the reaction tube and the electrode in a cross section from above.
[0003]
According to FIGS. 1 to 3, a reaction tube 2 and an inlet flange 21 are provided concentrically on the inside of a cylindrical heating source 1 whose outside is surrounded by a heat insulating material. A seal flange 20 that can move up and down while the holding means mounting base 4 is placed is provided at the lower part of the holder. A holding means 3 for holding a substrate 5 (for example, a silicon wafer) in multiple stages is placed on the holding means mounting table 4.
[0004]
The seal flange 20 is configured to form a reaction chamber 6 that performs a process surrounded by the reaction tube 2 and the inlet flange 21 when the seal flange 20 moves up and down by a lifting mechanism 24 and moves up to a predetermined position. At this time, a sealing material (not shown) is provided between the reaction tube 2 and the inlet flange 21 and between the inlet flange 21 and the seal flange 20 so that the reaction chamber 6 is hermetically closed.
[0005]
The reaction tube 2 has a structure in which a buffer chamber 7 (a space formed by the wall of the reaction tube 2 and the wall 26) for gas supply to the reaction chamber 6 is installed. The buffer chamber 7 and the reaction chamber 6 communicate with each other through a small hole 12 provided in the wall 26. The buffer chamber 7 also serves as a remote plasma discharge chamber.
[0006]
The buffer chamber 7 is provided with at least two electrode members composed of the electrode protection tube 10 and the electrode 11. The electrode protection tube 10 has a pipe shape with one side open, and the open end is disposed in the side of the reaction tube and the other end is disposed in the buffer chamber 7 so as to penetrate the buffer chamber 7 in the longitudinal direction. By inserting the electrode 11 from the open end described above, the electrode 11 is arranged inside the buffer chamber 7, while the electrode 11 is not in direct contact with the reaction gas.
[0007]
The electrode 11 uses a flexible member considering the bending of the electrode protection tube 10.
In addition, the electrode 11 can be applied with high-frequency power output from the high-frequency power supply 16 via the matching unit 17.
[0008]
The inlet flange 21 is provided with an exhaust port 8 so that the gas inside the reaction tube 2 can be exhausted.
[0009]
FIG. 4 shows another example of the apparatus in which the exhaust port 8 is provided at the lower part of the reaction tube 2 and the inlet flange 21 is not provided.
[0010]
5 and 6, the electrode protection tube 10 is a component independent of the reaction tube 2 and is inserted into the buffer chamber 7 through the seal flange 20. A sealing material (not shown) is provided in the penetrating portion.
[0011]
7 and 8 are enlarged sectional views of the buffer chamber configuration.
As shown in FIG. 7, a gas introduction port 9 is provided on the side of the reaction chamber, and the reaction gas introduced from the introduction port 9 flows into the buffer chamber 7 through the gas nozzle 25, and then passes through path A, path B, and path. a, a path b, through a plurality of small holes 12 provided on the central axis side of the reaction chamber 6 of the buffer chamber 7, and a plurality of objects to be processed placed at equal intervals in multiple stages on the holding means 3 in the reaction tube 2 The structure is supplied to the substrate 5.
[0012]
In order to equalize the pressure in the buffer chamber 7 or the reaction gas velocity from the small hole 12 to the reaction chamber 6, the buffer chamber 7 is vertically long and has a number of holes formed integrally with the gas inlet 9. In some cases, a reactive gas is supplied into the buffer chamber 7 through the hole of the gas nozzle. The gas inlet 9 and the porous gas nozzle may be formed by welding.
At this time, the reactive gas is activated by the plasma 15 generated in the buffer chamber 7 which also serves as a discharge.
[0013]
FIG. 8 is an example in which the relative positions of the small holes 12 with respect to the electrodes 11 are different. In this case, the path c passes through the bag small path portion, and not only the gas flow distance to the small holes 12 is increased but also the path d. A puddle will be generated.
[0014]
Next, the operation of this processing apparatus will be described.
The inside of the reaction tube 2 is raised to a predetermined temperature by the heating source 1.
After a plurality of substrates to be processed 5 are transferred to the holding means 3 by a robot (not shown), the seal flange 20 is raised by the lifting mechanism 24. The seal flange 20 rises to a predetermined position and constitutes the reaction tube 2, the inlet flange 21, and the reaction chamber 6 hermetically closed by a seal material (not shown), and the holding means mounting base 4, the holding means 3, and The substrate 5 to be processed is loaded into the reaction tube 2.
Thereafter, while monitoring with a pressure control system (not shown), a conductance valve (not shown) is driven to automatically control to a predetermined pressure.
[0015]
The reaction gas is introduced into the buffer chamber 7 from the gas supply unit 23 through the gas introduction port 9, and is introduced into the reaction chamber 6 through the small hole 12 while being activated by the plasma 15 generated by the electrode 11. 5 is processed to form a desired film. Excess reaction gas is exhausted from the exhaust port 8.
After the heat treatment is completed, the substrate 5 to be processed is collected in the reverse procedure.
[0016]
[Problems to be solved by the invention]
When the density of the active species of the reaction gas is small, the processing efficiency and the processing speed are lowered.
In addition, since the active species are deactivated by the collision with the wall surface, the density decreases as the distance until the contribution to the treatment (that is, the distance from the activated region of the plasma 15 to the substrate to be treated) increases. Therefore,
(1) Activated by high density plasma. (Increase the density of active species at the time of excitation)
(2) Transport the active species to the substrate to be processed without deactivating it.
It becomes important.
[0017]
(Problem 1)
As a reaction gas flow path in the buffer chamber 7, it is desirable to pass between the electrodes 11 having a high plasma density. However, as shown in FIG. 7, in the structure of the prior art, the reaction gas that has passed through the path a and the path b is activated species. The density of will become small.
[0018]
(Problem 2)
The reaction gas preferably passes through the small hole 12 immediately after becoming the active species in the buffer chamber 7, but as shown in FIG. 7 and FIG. 8, in the conventional technique, the plasma 15 and the small hole 12 are not in close proximity. The density decreases before the active species passes through the small hole 12.
[0019]
(Problem 3)
Since the installation positions of the electrode protection tube 10, the electrode 11, and the small hole 12 in the buffer chamber 7 are not optimized, the deactivation of the active species is promoted in the bag path like the path c as shown in FIG. In particular, when the puddle is accumulated as in the path d, the density is further reduced.
[0020]
Therefore, an object of the present invention is to provide a processing apparatus and a semiconductor device manufacturing method having high processing speed (throughput) and high processing efficiency by solving the problems of the prior art and increasing the activation density of the supply gas. There is.
[0021]
[Means for Solving the Problems]
The first invention is
A plurality of substrates stacked and accommodated, and a reaction tube that forms a processing space for the substrates; and
A plurality of small holes are provided in the stacking direction of the substrate, and a wall member that forms a buffer space for the reaction gas together with a part of the wall of the reaction tube;
Gas introduction means communicating with the buffer space;
And at least two rod-shaped electrode members that are disposed in the buffer space and that extend in the longitudinal direction of the buffer space to form an activated region of the reaction gas,
The gas introduced from the gas introduction means is activated in the buffer space, introduced into the reaction space through the plurality of small holes, and a substrate processing apparatus for processing the substrate,
In the substrate processing apparatus, the electrode member is provided in the vicinity of at least the wall member.
[0022]
Moreover, 2nd invention is the substrate processing apparatus which adjoined the said electrode member at least within the range of 0-5 mm to the said wall member.
[0023]
The third invention is a substrate processing apparatus in which the electrode member is in close contact with at least the wall member.
[0024]
Moreover, 4th invention is the substrate processing apparatus which has arrange | positioned the said electrode member so that the said small hole may be arrange | positioned between the said electrode members.
[0025]
The fifth invention is a substrate processing apparatus in which the reaction tube, the wall member, and the electrode member are welded to form an integrated structure.
[0026]
In addition, the sixth invention,
Placing the substrate in the reaction space in the reaction tube;
Introducing a reaction gas into a reaction gas buffer space formed by a part of a wall of the reaction tube and a wall member provided with a small hole;
Activating the gas introduced into the buffer space with at least two electrode members provided in the buffer space and proximate to the wall member;
Introducing the activated gas into the processing space through the small holes and processing the substrate;
The manufacturing method of the semiconductor device containing this.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to the optimization of the relative positions of the electrode member and small hole 12 composed of the electrode protection tube 10 and the electrode 11 in the buffer chamber 7 for the purpose of increasing the density of active species of the reaction gas.
[0028]
Embodiments of the present invention will be described with reference to FIGS.
The processing apparatus described in the related art is different from the processing apparatus illustrated in FIGS. 9, 10, and 11, and the rest is the same as the processing apparatus described in the prior art. The same reference numerals are used for the same members used in the description of the prior art.
[0029]
In FIG. 9, the two electrode protection tubes 10 are positioned in the vicinity of the wall 26 on the small hole 12 side that constitutes the buffer chamber 7 (preferably, a member (wall surface) that forms the electrode protection tube 10 and the buffer chamber 7). It is sufficient that the distance between the electrode protection tube 10 is 0 to 5 mm, and the electrode protection tube 10 is in close contact with the wall surface). A small hole is located between the electrode protection tubes 10). Thus, the distance between the plasma 15 and the small hole 12 is the shortest.
[0030]
By bringing the two electrode protection tubes 10 close to the members constituting the buffer chamber 7, the main gas flow path can be limited. Further, by providing the small hole 12 at a position where the limited main gas flow path passes between the two electrode protection tubes 10, the reactive gas can be efficiently passed through the region 15 having a high plasma density. It is possible to increase the seed density.
[0031]
In the case of FIG. 9, the reaction gas path in the buffer chamber 7 is roughly divided into a path D, a path E, a path e, and a path f. The path D and the path E are the main gas flow paths, and most of the reaction gas passes between the two electrode protection tubes 10, that is, the region where the density of the plasma 15 is high.
[0032]
In addition, since the plasma 15 and the small hole 12 are positioned in the immediate vicinity, and an unnecessary puddle portion is minimized, it is possible to minimize the deactivation of the active species generated in the path D and the path E. Further, even if it is deactivated before entering the small hole 12, it can be activated again by the plasma 15.
[0033]
On the other hand, the path e and path f that do not pass between the two electrode protection tubes 10 also pass in the vicinity of the plasma 15 immediately before the small hole 12, and therefore the density of active species increases, and the path C Similarly to the route D, there is little deactivation until it is introduced into the reaction chamber 6.
[0034]
That is, according to the present invention, the following becomes possible.
(1) It can be activated by high density plasma. (Increase the density of active species at the time of excitation)
(2) The active species can be transported to the substrate to be processed without deactivation.
[0035]
It is also a feature of the present invention that there is no need to control the gas flow path before becoming the active species so that there is no difference in the density of the active species in the paths D and E.
[0036]
Here, if the electrode protection tube 10 and the buffer chamber 7 are brought into close contact with each other, the path e and the path f are cut off, so that the gas path can be limited to the path D and the path E. This is effective in that it is supplied to the processing substrate. Furthermore, since there is no gap through which the paths e and f pass, there is no variation in the reaction gas activation density between apparatuses, which is even better.
[0037]
FIG. 10 shows a second embodiment, in which the gas nozzle 25 and the small hole 12 are arranged between the two electrode protection tubes 10 so that the gas supplied from the gas nozzle 25 linearly passes through the plasma 15 and the small hole 12. This is another configuration example that can increase the density of active species as in FIG.
[0038]
FIG. 11 is also a third embodiment showing another configuration example of the present invention.
One of the two electrode protection tubes 10 is close to the inner member (wall 26) constituting the buffer chamber 7 and the other is close to the outer member (that is, the inner wall of the reaction tube 2) to limit the main gas flow path. ing. A small hole 12 is provided at a position where the main gas flow path I passes between the two electrode protection tubes 10.
9 and 10, the distance between the plasma 15 and the small hole 12 becomes longer, and as a result, a puddle portion is formed. However, the loss is caused by bringing the electrode protection tube 10 closer to the member (wall surface) constituting the buffer chamber 7. It becomes possible to reduce life.
[0039]
Therefore, by optimizing the arrangement of the buffer chamber 7, the electrode protection tube 10, and the small holes 12, the density of reactive species of the reactive gas can be increased.
[0040]
The above-described configuration is an example applied to the form of the processing apparatus of FIGS. 5 and 6, but it goes without saying that any of the examples of FIGS. 1 to 4 can be applied.
[0041]
As described above, the density of the active species of the reaction gas can be improved by optimizing the relative positions of the buffer chamber 7, the electrode protection tube 10, and the small holes 12. When considering the reproducibility and reproducibility, it is preferable that the relative position has no variation.
[0042]
In the above-described example, since the electrode protection tube 10 is independent of the buffer chamber 7 and the small hole 12, an assembly error occurs. Therefore, it is conceivable that the reaction gas activation concentration varies between apparatuses.
Therefore, it is possible to suppress variations by applying a reaction tube in which the reaction tube 2, the walls constituting the buffer chamber 7, the small holes 12, and the electrode protection tube 10 are integrated. Each material is made of quartz, and there is no problem if it is integrally formed by welding.
[0043]
In addition, if the above-described substrate processing apparatus is used, high-quality semiconductor devices can be produced.
That is, placing the substrate in the reaction space in the reaction tube;
Introducing a reaction gas into a reaction gas buffer space formed by a part of a wall of the reaction tube and a wall member provided with a small hole;
Activating the gas introduced into the buffer space with at least two electrode members provided in the buffer space and proximate to the wall member;
Introducing the activated gas into the processing space through the small holes and processing the substrate;
If a semiconductor device is manufactured by a method for manufacturing a semiconductor device including the above, a semiconductor device with higher quality can be obtained.
[0044]
【The invention's effect】
According to the present invention, in a remote plasma processing apparatus that collectively processes a plurality of substrates,
(1) The treatment speed (throughput) can be increased by increasing the activation density of the reaction gas.
(2) Since reaction gas can be activated efficiently, there is little waste of reaction gas. (Running cost reduction)
(3) It is possible to provide a highly reproducible and reliable device with little variation between devices.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a conventional processing apparatus. FIG. 2 is a longitudinal sectional view showing a conventional reaction chamber. FIG. 3 is a sectional view taken along line XX ′ of FIG. FIG. 5 is a longitudinal sectional view showing a conventional processing apparatus. FIG. 6 is a sectional view taken along line YY ′ of FIG. 5. FIG. 7 is an enlarged sectional view showing a conventional buffer chamber. FIG. 9 is an enlarged sectional view showing the buffer chamber according to the present invention. FIG. 10 is an enlarged sectional view showing the buffer chamber according to the present invention. FIG. 11 is an enlarged sectional view showing the buffer chamber according to the present invention. ]
DESCRIPTION OF SYMBOLS 1 Heating source 2 Reaction tube 3 Holding means 4 Holding means mounting base 5 Substrate 6 Reaction chamber 7 Buffer chamber 8 Exhaust port 9 Gas inlet 10 Electrode protective tube 11 Electrode 12 Small hole 15 Plasma 16 High frequency power supply 17 Matching device 20 Seal flange 21 Inlet flange 22 Rotating mechanism 23 Gas supply unit 24 Elevating mechanism 25 Gas nozzle 26 Walls A to I Gas path in buffer room (high density)
a to j Buffer room gas path (low density)

Claims (4)

A plurality of substrates stacked and accommodated, and a reaction tube that forms a processing space for the substrates; and
A plurality of small holes are provided in the stacking direction of the substrate, and a wall member that forms a reaction gas buffer space together with a part of the wall of the reaction tube
Gas introduction means communicating with the buffer space;
And at least two rod-shaped electrode members that are disposed in the buffer space and that extend in the longitudinal direction of the buffer space to form an activated region of the reaction gas,
The gas introduced from the gas introduction means is activated in the buffer space, introduced into the processing space through the plurality of small holes, and a substrate processing apparatus for processing the substrate,
A substrate processing apparatus, wherein the electrode member is provided in the vicinity of at least the wall member. The substrate processing apparatus according to claim 1, wherein a distance between the electrode member and the wall member is 5 mm or less. The substrate processing apparatus according to claim 1, wherein the electrode member is disposed such that the plurality of small holes are disposed between the electrode members. A plurality of substrates stacked and accommodated, and a reaction tube that forms a processing space for the substrates; and
  A plurality of small holes are provided in the stacking direction of the substrate, and a wall member that forms a buffer space for the reaction gas together with a part of the wall of the reaction tube;
  Gas introduction means communicating with the buffer space;
  And at least two rod-shaped electrode members that are disposed in the buffer space and that extend in the longitudinal direction of the buffer space to form an active region of the reaction gas,
  The gas introduced from the gas introduction means is activated in the buffer space, introduced into the processing space through the plurality of small holes, and a substrate processing apparatus for processing the substrate,
  A substrate processing apparatus, wherein the electrode member is provided in close contact with the wall member.

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