JP4903022B2 - Gas head and semiconductor manufacturing equipment - Google Patents

Description

  The present invention relates to a gas head and a semiconductor manufacturing apparatus.

  In semiconductor manufacturing equipment such as etching equipment and CVD equipment, a processing gas (processing gas component: a single gas or a mixed gas such as a reactive gas, a raw material gas, an inert gas, etc. used for a chemical reaction) is introduced into a processing chamber which is a reaction space. The substrate placed on the substrate stage is processed by a chemical reaction.

FIG. 9A is a cross-sectional view of the semiconductor manufacturing apparatus according to the first conventional example. In this semiconductor manufacturing apparatus, the first gas is directly introduced from the center of the ceiling surface of the processing chamber (see, for example, Patent Document 1). When the first gas 1 is introduced without using the gas head, high-speed gas is ejected from the gas ejection port 28 into the processing chamber 11, and convection occurs against the substrate 5 and the side wall 12.
FIG. 9B is a gas flow velocity distribution diagram in the processing chamber (right half). It can be seen that convection occurs in the region 91 where the gas flow velocity is fast, and a convection eye 95 is generated in the center. When convection occurs as shown in FIG. 9A, a gas containing decomposition products and secondary products after reacting with the substrate 5 and a gas not suitable for substrate processing reacting with the wall material of the processing chamber 11 are obtained. Return to the substrate 5 again. As a result, it has been confirmed that the stability and reproducibility of substrate processing is hindered. As a result, it becomes difficult to achieve uniform processing of the substrate.

FIG. 10A is a cross-sectional view of a semiconductor manufacturing apparatus according to a modification of the first conventional example. When introducing two types of processing gases 1 and 2 into the processing chamber 11, a second gas jet 48 is provided around the first gas jet 28.
FIG. 10B is a distribution diagram of the gas concentration in the processing chamber (right half). In this modification, it can be seen that the high-concentration region 91 of the first gas and the high-concentration region 92 of the second gas are generated without obtaining a homogeneous mixture of two or more kinds of processing gases. When the concentration distribution occurs in the processing chamber as described above, a difference occurs in the processing within the substrate surface. If the gas ejection ports 28 and 48 shown in FIG. 10A and the substrate 5 are separated from each other, two or more kinds of processing gases can be uniformly mixed in the processing chamber 11. However, if the gas ejection ports 28 and 48 and the substrate 5 are separated from each other, the space in the processing chamber 11 becomes large and convection occurs.

Therefore, a gas head for introducing the processing gas into the processing chamber is used.
FIG. 11A is a cross-sectional view of a semiconductor manufacturing apparatus according to a second conventional example. In this semiconductor manufacturing apparatus, the first gas 1 is introduced through the gas head 50 disposed on the ceiling of the processing chamber (see, for example, Patent Document 2). The gas head 50 is formed with an internal space 51 into which the first gas 1 is introduced, and a shower hole 52 serving as a gas outlet is formed on the lower surface of the internal space. Then, after the introduced first gas is dispersed in the internal space 51, the first gas is supplied into the processing chamber through the shower hole 52 in a uniform flow.

FIG. 11B is a cross-sectional view of a semiconductor manufacturing apparatus according to a modification of the second conventional example. Even when two or more kinds of processing gases are introduced, they are first introduced into the internal space 51. In addition, in order to mix each processing gas, each processing gas is introduce | transduced at high speed and is stirred by a turbulent flow. However, since this turbulent flow adversely affects the substrate processing, the processing gas is supplied to the processing chamber after the turbulent flow is reduced in the internal space 51 of the gas head.
JP 2005-149956 A Japanese Patent Laid-Open No. 10-298763

However, when a highly reactive gas / active gas is used as a processing gas, the processing gas loses its reactivity / activity as the number of collisions with an obstacle increases. In the second conventional example and its modification shown in FIG. 11, there is a problem that the reactivity / activity disappears during the process gas passes through the shower hole 52. In this case, a chemical reaction necessary for the substrate processing cannot be obtained, and the processing efficiency is lowered.
The present invention has been made to solve the above-described problems, and provides a gas head and a semiconductor manufacturing apparatus capable of improving processing efficiency and capable of realizing uniform processing. Objective.

In order to solve the above-described problems, a gas head according to the present invention includes a first gas introduction port that introduces a first gas, a gas ejection port that ejects gas into a processing chamber, and the gas injection port from the first gas introduction port. A gas head comprising: a gas flow path for flowing gas to an outlet; and an intermediate member fixed to an inner surface of the gas flow path in the gas flow path , wherein the gas flow path is the first gas The area of the region sandwiched between the inner surface of the gas flow path and the intermediate member increases from the inlet to the gas outlet , and the intermediate member shares the bottom surfaces of the two truncated cones. and wherein the shape der Rukoto.
It is desirable that the two surfaces facing the bottom surface of the truncated cone are both horizontal surfaces perpendicular to the direction in which the first gas is introduced.
By increasing the flow channel area of the gas flow channel, that is, the area of the region sandwiched between the inner surface of the gas flow channel and the intermediate member, the gas ejection speed from the gas ejection port can be reduced. Gas convection can be prevented. As a result, processing stability and reproducibility are ensured, and uniform processing can be realized. Further, it becomes possible to eject the gas in a state in which the reactivity / activity is maintained, and the processing efficiency can be improved.

By changing the flow direction of the first gas toward the peripheral edge of the gas head, it becomes possible to prevent gas convection in the processing chamber and to achieve uniform processing.

The first gas introduction port is provided in a central portion of the gas head, and when an intermediate member is provided, the gas flow path is enlarged toward the central portion of the gas head in the vicinity of the gas jet port. It is desirable that
Further, it is desirable that the gas flow path expands toward the peripheral edge of the gas head in the vicinity of the gas ejection port.
According to these structures, it becomes possible to eject gas equally with respect to the whole process chamber, and a uniform process can be implement | achieved.

Moreover, the 2nd gas jet nozzle which ejects 2nd gas to the said gas flow path may be provided in the vicinity of the area | region where the flow direction of the said 1st gas changes with the said intermediate member.
According to this configuration, since the second gas can collide with the first gas whose flow direction has changed at a wide angle, the first gas and the second gas can be homogeneously mixed. As a result, uniform processing can be realized in the processing chamber.

Moreover, it is desirable that the second gas ejection port is provided so that the ejected second gas collides with the first gas at an angle of 90 ° or more.
According to this configuration, the first gas and the second gas can be homogeneously mixed. As a result, uniform processing can be realized in the processing chamber.

Further, it is desirable that a corrosion resistant coating is applied to the inner surface of the gas flow path.
According to this configuration, it is possible to prevent the inner surface of the gas flow path from being corroded by the gas flowing through the gas flow path. As a result, processing stability and reproducibility are ensured, and uniform processing can be realized. Further, the durability of the gas head can be improved.

Moreover, it is desirable that the inner surface of the gas flow path is covered with a member having deactivation resistance.
According to this configuration, when the gas flowing through the gas flow path collides with the inner surface of the gas flow path, the reactivity / activity is not lost. As a result, the activated gas can be ejected into the processing chamber, and the processing efficiency can be improved.

On the other hand, a semiconductor manufacturing apparatus according to the present invention includes the gas head described above.
According to this configuration, since the gas head described above is provided, it is possible to provide a semiconductor manufacturing apparatus capable of improving the processing efficiency and realizing a uniform processing.

  The gas head according to the present invention can prevent gas convection in the processing chamber. As a result, processing stability and reproducibility are ensured, and uniform processing can be realized. Further, it becomes possible to eject the gas in a state in which the reactivity / activity is maintained, and the processing efficiency can be improved. Furthermore, the first gas and the second gas can be mixed homogeneously, and uniform processing can be realized.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, taking a surface treatment apparatus for performing a film forming process as an example. In each drawing used for the following description, the scale of each member is appropriately changed to make each member a recognizable size.
(First embodiment)
First, a first embodiment of the present invention will be described.
FIG. 1 is a cross-sectional view of a semiconductor manufacturing apparatus and a gas head according to the first embodiment. The semiconductor manufacturing apparatus 10 includes a gas head 20 on the ceiling of the processing chamber 11 where the substrate 5 is disposed.

(Semiconductor manufacturing equipment)
The semiconductor manufacturing apparatus 10 includes a cylindrical processing chamber 11. The wall surface of the processing chamber 11 is made of an Al material or the like. A substrate stage 14 on which a substrate to be processed (hereinafter referred to as “substrate”) 5 is placed is provided below the inside of the processing chamber 11. The substrate stage 14 is provided with temperature adjusting means such as a heater and a refrigerant flow path so that the substrate temperature can be controlled.

  The processing chamber 11 includes a gas introduction system and a gas discharge system. The gas discharge system mainly includes a gas discharge port formed on the bottom surface of the processing chamber 11 and an exhaust pump (not shown) connected to the gas discharge port. The gas introduction system mainly includes a first gas source (not shown) for storing the first gas, a first gas supply pipe 16 extending from the first gas source, and a gas connected to the first gas supply pipe. And a head 20. When processing the substrate 5, the first gas is introduced into the processing chamber 11 from the first gas source at an arbitrary flow rate, the processing chamber is controlled to an arbitrary processing pressure by the pressure adjustment valve, and the surplus first gas is supplied. The reaction by-product gas is discharged by a gas discharge system.

  The gas head 20 includes a head body 22 and an intermediate member 24. The head main body 22 is formed in a disk shape from an Al material or the like, and is disposed on the ceiling portion of the processing chamber 11. A first gas introduction port 26 for introducing a first gas is opened at the center of the upper surface of the head body 22 (the outer surface of the processing chamber 11). The first gas supply pipe 16 described above is connected to the first gas inlet 26. In addition, a gas ejection port 28 that ejects gas into the processing chamber 11 is opened at the center of the lower surface of the head body 22 (inner side surface of the processing chamber 11). The opening area of the gas outlet 28 is larger than the opening area of the first gas inlet 26. A gas passage 27 through which gas flows from the first gas inlet 26 to the gas outlet 28 is formed through the head body 22. The side surface 22 a of the gas flow path 27 is formed as a tapered surface that opens toward the processing chamber 11.

  An intermediate member 24 made of an Al material or the like is provided inside the gas flow path 27. The intermediate member 24 is fixed to the head main body 22 by a support member 23. A cross section taken along line AA in FIG. 1 is shown in FIG. As shown in FIG. 2A, a plurality of (for example, four) support members 23 are equally arranged in the circumferential direction of the intermediate member 24, and the intermediate member 24 is supported.

The intermediate member 24 changes the flow direction of the first gas toward the peripheral edge of the gas head 20. That is, the intermediate member 24 changes the flow direction of the first gas along the central axis direction (the vertical direction in FIG. 1) of the gas head 20 to the radial direction of the gas head 20 (the horizontal direction in FIG. 1). . The intermediate member 24 has a shape in which the bottom surfaces of the two truncated cones are shared. Therefore, the upper surface of the intermediate member 24 with which the first gas collides is a horizontal plane substantially perpendicular to the central axis direction of the gas head 20 . The lower surface of the intermediate member 24 is also a horizontal plane.

An upper half portion 24 a of the side surface of the intermediate member 24 is formed in a tapered surface that tapers toward the outside of the processing chamber 11. The tapered surface of the upper half portion 24a on the side surface of the intermediate member 24 and the tapered surface of the inner surface of the gas flow path 27 are formed at substantially the same inclination angle and arranged at equal intervals.
2A is a cross-sectional view taken along line AA in FIG. 1, and FIG. 2B is a cross-sectional view taken along line BB in FIG. As shown in FIG. 2A, the gas flow path 27 in the first embodiment has a ring-shaped flow path cross section. Since the upper half portion 24a of the side surface of the intermediate member 24 and the side surface 22a of the gas flow path are arranged at equal intervals, the width D1 of the flow path cross section in FIG. 2A is the flow path cross section in FIG. Is equal to the width D2. However, since the radius R2 of the intermediate member 24 in FIG. 2B is larger than the radius R1 of the intermediate member 24 in FIG. 2A, the flow path area in FIG. It is larger than the road area. That is, the channel area of the gas channel 27 increases from the first gas inlet to the gas outlet.

Returning to FIG. 1, the lower half portion 24 b of the side surface of the intermediate member 24 is formed in a tapered surface that tapers toward the inside of the processing chamber 11.
FIG. 2C is a cross-sectional view taken along the line CC in FIG. The channel area in FIG. 2 (c) is larger than the channel area in FIG. 2 (b). In particular, the outer diameter (R3 + D3) of the gas flow path 27 in FIG. 2 (c) is larger than the outer diameter (R2 + D2) of the gas flow path 27 in FIG. 2 (b). That is, the gas flow path 27 expands toward the peripheral edge of the gas head in the vicinity of the gas outlet. Thereby, the gas ejection direction from a gas ejection port can be extended in the peripheral part direction of a process chamber (board | substrate).

  Further, the inner diameter R3 of the gas flow path 27 in FIG. 2C is smaller than the inner diameter R2 of the gas flow path 27 in FIG. That is, the gas flow path 27 is expanded toward the center of the gas head in the vicinity of the gas jet port. Thereby, the gas ejection direction from the gas ejection port can be extended from the extending direction of the gas flow path to the central portion of the processing chamber (substrate). As a result, gas can be ejected to substantially the entire processing chamber (substrate), and uniform processing on the substrate can be realized.

  FIG. 3 is a cross-sectional view of a gas head according to a modification of the first embodiment. 4A is a cross-sectional view taken along the line DD in FIG. 3, FIG. 4B is a cross-sectional view taken along the line EE in FIG. 3, and FIG. 4C is a cross-sectional view taken along the line F in FIG. It is sectional drawing in the -F line. As shown in FIG. 3, in this modification, a plurality of through holes 37 a are formed in the gas head 30. The inner diameter of each through-hole 37a is enlarged from the first gas inlet 36 to the gas outlet 38. And as shown to Fig.4 (a), the gas flow path 37 is comprised by the through-hole group which arranged the multiple (8 in FIG. 4 (a)) through-hole 37a equally in the circumferential direction. The flow passage area of the gas flow passage 37 increases from the first gas inlet to the gas outlet. In this case, the central region of the through hole group functions as the intermediate member 34.

  Also in this modification, the flow channel area of the gas flow channel 37 is enlarged from FIG. 4A to FIG. 4C. In particular, the outer diameter T of the through hole group increases from FIG. 4 (b) to FIG. 4 (c). That is, the gas flow path 37 is expanded toward the peripheral edge of the gas head in the vicinity of the gas outlet. The inner diameter R of the through hole group increases from FIG. 4B to FIG. 4C. That is, the gas flow path 37 is also enlarged toward the center of the gas head in the vicinity of the gas outlet. In addition, the opening part of each through-hole which comprises a gas jet nozzle becomes the ellipse shape which made the major axis direction correspond to the radial direction of a gas head.

Next, the operation of the gas head according to the first embodiment will be described.
Fig.5 (a) is explanatory drawing of the flow direction of the gas in the gas head of 1st Embodiment. The first gas 1 is introduced into the first gas introduction port along the central axis of the gas head 20 by the first gas supply pipe 16. When the first gas 1 introduced at high speed collides with the upper surface of the intermediate member 24, the flow direction of the first gas 1 changes toward the peripheral edge of the gas head 20. Further, the first gas 1 is guided to the side surface 22 a of the gas flow path 27 and flows into the gas flow path 27. Since the flow channel area of the gas flow channel 27 increases from the first gas introduction port 26 to the gas ejection port 28, the flow rate of the first gas decreases toward the downstream side of the gas flow channel 27. Accordingly, the first gas is ejected from the gas ejection port 28 at a low speed.

  In this regard, in the first conventional example shown in FIG. 9, the first gas 1 ejected into the processing chamber 11 at high speed collides with the substrate stage 14 and the side wall 12, thereby causing convection in the processing chamber 11. As a result, a gas containing decomposition products and secondary products after reacting with the substrate 5 and a gas not suitable for substrate processing that reacts with the wall material of the processing chamber 11 return to the substrate 5 again. As a result, the stability and reproducibility of substrate processing is hindered.

In contrast, in the present embodiment, since the first gas is ejected from the gas ejection port at a low speed, convection of the first gas does not occur in the processing chamber.
FIG. 5B is a gas flow velocity distribution diagram in the processing chamber (right half) of the first embodiment. In FIG. 5B, the equal gas flow velocity line is indicated by a two-dot chain line, the high velocity region 91 of the gas flow velocity is indicated by a vertical and horizontal lattice pattern, and the low velocity region 92 is indicated by an oblique lattice pattern. According to FIG. 5B, the high velocity region 91 exists in the vicinity of the gas jet port, but the flow rate of the first gas decreases as the distance from the gas jet port increases, and the vicinity of the substrate 5 becomes the low velocity region 92. ing. Thus, since convection does not occur in the processing chamber 11, the gas after the substrate processing is discharged from the gas discharge port below the substrate stage. Further, the gas that has reacted with the wall material of the processing chamber 11 does not return to the substrate again. Therefore, it becomes possible to ensure the stability and reproducibility of the substrate processing, and it is possible to realize uniform processing on the substrate.

On the other hand, the second conventional example shown in FIG. 11A has a problem that the reactivity / activity disappears in the process of the first gas 1 passing through the shower hole 52. In this case, a chemical reaction necessary for the substrate processing cannot be obtained, and the processing efficiency is lowered.
On the other hand, in the gas head of the first embodiment, since the chance of collision of the first gas with the gas head constituent members is minimized, the first gas is supplied to the processing chamber while maintaining the reactivity / activity. It is possible to erupt. Therefore, the substrate processing efficiency can be improved.

Thus, when the first gas having reactivity / activity is introduced, it is desirable to apply a corrosion-resistant coating to the inner surface of the gas flow path. Specifically, Y ₂ O ₃ or the like can be employed as the coating material. According to this structure, it can prevent that the inner surface of a gas flow path is corroded by the gas which distribute | circulates the inside of a gas flow path. As a result, processing stability and reproducibility are ensured, and uniform processing can be realized. Further, the durability of the gas head can be improved.

  Further, when the first gas having reactivity / activity is introduced, it is desirable that the inner surface of the gas flow path is covered with a member having deactivation resistance. Specifically, ceramics such as high-purity alumina, sapphire, or the like can be used as the member having anti-deactivation activity. According to this configuration, when the gas flowing through the gas flow path collides with the inner surface of the gas flow path, the reactivity / activity is not lost. As a result, the activated gas can be ejected into the processing chamber, and the processing efficiency can be improved.

  Furthermore, in the gas head according to the first embodiment, the gas flow path expands toward the central portion and the peripheral portion of the gas head in the vicinity of the gas ejection port. Thereby, the gas ejection direction from the gas ejection port can be expanded not only in the extending direction of the gas flow path but also in the central direction and the peripheral edge direction of the processing chamber (substrate). As a result, gas can be ejected to substantially the entire processing chamber (substrate), and uniform processing on the substrate can be realized.

(Second Embodiment)
Next, a second embodiment of the present invention will be described.
FIG. 6A is a cross-sectional view of a gas head according to the second embodiment. The gas head according to the first embodiment introduces only the first gas as the processing gas, but the gas head 20 according to the second embodiment differs in that the second gas is introduced in addition to the first gas. Yes. Note that detailed description of portions having the same configuration as in the first embodiment is omitted.

FIG. 6B is a cross-sectional view taken along the line GG in FIG. As shown in FIG. 6B, a plurality of second gas introduction ports 46 are provided around the first gas introduction port 26 in the gas head 20. In the present embodiment, eight second gas introduction ports 46 are equally arranged in the circumferential direction.
Returning to FIG. 6A, the second gas introduction path 41 is provided downward from the second gas introduction port 46. A second gas ejection path 42 is formed from the lower end of the second gas introduction path 41 toward the center of the gas head 20. A second gas flow path 40 is configured by the second gas introduction path 41 and the second gas ejection path 42. A second gas ejection port 48 is formed at the tip of the second gas ejection path 42. The second gas ejection port 48 opens to the gas flow path 27 in the vicinity of the upper surface of the intermediate member 24.

  Fig.7 (a) is explanatory drawing of the flow direction of the gas in the gas head of 2nd Embodiment. When the first gas 1 introduced along the central axis of the gas head 20 collides with the upper surface of the intermediate member 24, the flow direction of the first gas 1 changes toward the peripheral edge of the gas head 20. On the other hand, the second gas 2 is ejected from the second gas ejection path 42 and the second gas ejection port 48 toward the center of the gas head 20. For this reason, the first gas 1 and the second gas 2 collide at an angle θ of 90 ° or more, which is close to a frontal collision.

  In the present embodiment, since the second gas ejection port 48 is formed near the upper surface of the intermediate member 24, the second gas 2 is applied to the first gas 1 whose flow direction has changed toward the peripheral edge of the gas head 20. It is possible to make a collision at an angle θ of 90 ° or more. Then, by causing the first gas 1 and the second gas 2 to collide at an angle θ of 90 ° or more, it becomes possible to disperse the second gas 2 in the first gas 1 and to mix them both homogeneously. Can do.

  FIG. 7B is a distribution diagram of the gas concentration in the processing chamber (right half). In FIG. 7B, the equal gas concentration line is indicated by a two-dot chain line, the high gas concentration region 91 of the first gas is indicated by a vertical and horizontal lattice pattern, and the high gas concentration region 92 of the second gas is indicated by an oblique lattice pattern. . According to FIG. 7B, the high concentration region 91 of the first gas exists near the first gas inlet of the gas head 20, and the high concentration region of the second gas exists near the second gas outlet. To do. In contrast, in the processing chamber 11 (particularly, in the vicinity of the substrate 5), the first gas concentration and the second gas concentration are equal. This indicates that the first gas and the second gas are homogeneously mixed.

  As described above, in the second embodiment, the second gas ejection port is provided near the upper surface of the intermediate member, and the second gas collides with the first gas whose flow direction has changed at an angle of 90 ° or more. did. According to this configuration, the first gas and the second gas can be mixed homogeneously and ejected into the processing chamber. As a result, uniform processing can be realized in the processing chamber.

  The inventor of the present application applied the second embodiment shown in FIG. 7 to an etching apparatus, etched a thin film on the substrate, and measured the etching rate distribution on the substrate. The modification of the first conventional example shown in FIG. 9 and the modification of the second conventional example shown in FIG. 11B were also applied to the etching apparatus, and the etching rate distribution was measured in the same manner.

In each etching apparatus, as a first gas, a mixture gas of 400 sccm of H ₂ gas and 800 sccm of N ₂ gas activated by irradiation with microwaves was introduced. As the second gas, 400 sccm of NF ₃ gas was introduced. The etchant is generated by mixing the first gas and the second gas. Then, the substrate temperature was set to 20 ° C., the substrate processing pressure was set to 220 Pa, and the thermal oxide film (SiO ₂ film) formed on the surface of the silicon substrate having a diameter of 300 mm was etched.

FIG. 8 is a graph of the measurement result of the etching rate distribution. In each graph of FIG. 8, the horizontal axis represents the distance from the center of the substrate, and the vertical axis represents the etching rate.
FIG. 8C shows the measurement results when the modified example of the first conventional example shown in FIG. 10 is adopted. According to the graph of FIG. 8C, the etching rate is low at the central portion and the peripheral portion of the substrate, and the etching rate is high at the middle portion between the two. That is, the distribution of the etching rate on the substrate is increased.

  In the modification of the first conventional example shown in FIG. 10A, the first gas 1 is introduced from the central portion of the processing chamber 11, and the second gas 2 is introduced from the peripheral portion thereof. However, since the first gas 1 and the second gas 2 are introduced so that the first gas 1 and the second gas 2 collide at a small angle of 90 ° or less, they are not mixed uniformly.

  Therefore, as shown in FIG. 10B, the central portion of the substrate 5 becomes the high concentration region 91 of the first gas, and the peripheral portion becomes the high concentration region 92 of the second gas. Moreover, the density | concentration of 1st gas and 2nd gas becomes equivalent between the center part of the board | substrate 5, and a peripheral part. In this equivalent concentration region, the first gas and the second gas are mixed and the amount of etchant generated increases, so that the etching rate increases as shown in FIG. On the other hand, in the central portion and the peripheral portion of the substrate 5, only the first gas or the second gas has a high concentration and the amount of etchant generated is reduced, so that the etching rate is reduced. As a result, as shown in FIG. 8C, it is considered that the etching rate distribution on the substrate becomes large.

FIG. 8B shows the measurement results when the modified example of the second conventional example shown in FIG. According to the graph of FIG. 8B, the etching rate distribution on the substrate is small, but the etching rate is generally small (about 60 angstroms / min).
In the modification of the second conventional example shown in FIG. 11B, the introduced first gas 1 and second gas 2 are uniformly mixed in the internal space 51 of the gas head 50 and supplied into the processing chamber. Therefore, it is considered that the etching rate distribution on the substrate becomes small. However, when the first gas introduced in an activated state passes through the shower hole 52, it collides with the wall surface repeatedly. As a result, the first gas is deprived of energy by the shower hole 52 and loses its reactivity / activity (deactivates). Therefore, it is considered that the amount of etchant generated decreases and the etching rate decreases as shown in FIG.

FIG. 8A shows the result when the second embodiment shown in FIG. 7A is adopted. According to the graph of FIG. 8A, an etching rate of about 70 Å / min is secured, and the distribution of the etching rate on the substrate is reduced.
In the second embodiment shown in FIG. 7A, since the chance of collision of the first gas with the gas head constituent members is minimized, the first gas is brought into the processing chamber while maintaining the reactivity / activity. It is possible to erupt. As a result, a decrease in the amount of etchant generated is prevented, and an etching rate can be ensured as shown in FIG. In the second embodiment, since the first gas and the second gas are introduced so as to collide with each other at an angle of 90 ° or more, the first gas and the second gas can be mixed uniformly. As a result, as shown in FIG. 7B, substantially the entire substrate 5 becomes an equal concentration region of the first gas and the second gas. Therefore, as shown in FIG. 8A, the distribution of the etching rate on the substrate is considered to be small.

It should be noted that the technical scope of the present invention is not limited to the above-described embodiments, and includes those in which various modifications are made to the above-described embodiments without departing from the spirit of the present invention. That is, the specific materials and configurations described in the embodiments are merely examples, and can be changed as appropriate.
For example, the shape of the intermediate member is not limited to the shape of the above-described embodiment, and may be a cone shape or a bell shape, for example. Moreover, the semiconductor manufacturing apparatus of the present invention is not limited to an etching apparatus, and can be applied to, for example, a CVD apparatus.

1 is a cross-sectional view of a semiconductor manufacturing apparatus and a gas head according to a first embodiment. It is sectional drawing in each part of FIG. It is sectional drawing of the gas head which concerns on the modification of 1st Embodiment. It is sectional drawing in each part of FIG. (A) is explanatory drawing of a gas flow, (b) is a distribution map of a gas flow velocity. It is sectional drawing of the gas head which concerns on 2nd Embodiment. (A) is explanatory drawing of a gas flow, (b) is a distribution map of gas concentration. It is a graph of the measurement result of the etching rate distribution on a board | substrate. It is explanatory drawing of the semiconductor manufacturing apparatus which concerns on a 1st prior art example. It is explanatory drawing of the semiconductor manufacturing apparatus which concerns on the modification of a 1st prior art example. (A) is explanatory drawing of the gas head which concerns on a 2nd prior art example, (b) is explanatory drawing of the gas head which concerns on the modification of a 2nd prior art example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... 1st gas 2 ... 2nd gas 5 ... Board | substrate 10 ... Semiconductor manufacturing apparatus 11 ... Processing chamber 20 ... Gas head 24 ... Intermediate | middle member 26 ... 1st gas introduction port 27 ... Gas flow path 28 ... Gas ejection port

Claims (9)

A first gas introduction port for introducing a first gas; a gas ejection port for ejecting gas into the processing chamber; a gas flow path for flowing gas from the first gas introduction port to the gas ejection port; and the gas flow path An intermediate member fixed to the inner surface of the gas flow path, and a gas head comprising:
The gas flow path has a shape in which an area of a region sandwiched between an inner surface of the gas flow path and the intermediate member increases from the first gas introduction port to the gas ejection port ,
The intermediate member has a gas head, wherein the shape der Rukoto obtained by sharing the bottom ends of two truncated cones. 2. The gas head according to claim 1, wherein two surfaces facing the bottom surface of the truncated cone are both horizontal surfaces perpendicular to a direction in which the first gas is introduced. The first gas introduction port is provided in a central portion of the gas head,
It said gas flow channel, gas head according to claim 1 or 2, characterized in that in the vicinity of the gas ejection port are expanding toward the center of the gas head.   4. The gas head according to claim 1, wherein the gas flow path is enlarged toward a peripheral portion of the gas head in the vicinity of the gas ejection port. 5. Wherein in the vicinity of the region where the intermediate member by the flow direction of the first gas changes, claims 1 to, wherein the second gas ejection port for ejecting the second gas in the gas flow path is provided Item 5. The gas head according to any one of items 4 to 5.   The gas head according to claim 5, wherein the second gas ejection port is provided so that the ejected second gas collides with the first gas at an angle of 90 ° or more.   The gas head according to any one of claims 1 to 6, wherein an inner surface of the gas flow path is provided with a corrosion-resistant coating.   The gas head according to any one of claims 1 to 6, wherein an inner surface of the gas flow path is covered with a member having anti-deactivation activity.   A semiconductor manufacturing apparatus comprising the gas head according to claim 1.

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