JPH01283391A - Etching device - Google Patents

Abstract

PURPOSE:To uniformly etch a substrate on an electrode and to improve the yield by supplying a processing gas from plural gas diffusers pierced with many shifted holes, impressing a power between the electrode and its counter electrode to convert the processing gas into plasma. CONSTITUTION:The processing gas such as CF4 is supplied from a gas source into a treating chamber capable of being evacuated. The upper electrode 34 and the lower electrode 20 are opposed in the treating chamber, and a semiconductor wafer 1 as the substrate to be treated is placed above the lower electrode 20. A power is impressed between both electrodes 34 and 20 from a high-frequency power source 47 to convert the processing gas into plasma. The wafer 1 is etched by the processing gas plasma to form a pattern. In this etching device, a baffle 37 is arranged at the processing gas supply part, and the processing gas is uniformly projected from the plural holes 44 of the upper electrode 34. In addition, the baffle 37 is composed of at least two gas diffusers, many shifted holes are provided to the diffusers at regular intervals. As a result, the flow of the processing gas is further uniformized, and the wafer 1 is uniformly etched.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to an etching device.

(Prior art) In recent years, various thin film etching devices that can simplify and automate the complex manufacturing process of semiconductor devices and form fine patterns with high precision have been developed. Plasma etching equipment that uses these components is attracting attention.

This plasma etching apparatus is, for example, JP-A-57-1
As disclosed in Japanese Patent No. 56034, for example, an aluminum electrode is provided in the lower part of an airtight container connected to a vacuum device, and an amorphous carbon electrode is provided in the upper part facing the aluminum electrode. An RF power source is connected to the amorphous carbon electrode and the aluminum electrode, and a substrate to be processed, such as a semiconductor wafer, is set on the aluminum electrode, and power is applied between each electrode from the power source. do.

At the same time, a desired processing gas is supplied between the electrodes.

Then, the processing gas is turned into plasma by the electric power, and the surface of the semiconductor wafer is etched by the processing gas turned into plasma.

Here, the above-mentioned processing gas is supplied by providing a large number of holes for diffusing the processing gas in an electrode body opposite to the electrode body on which the wafer is installed, and connecting a gas supply pipe to supply the processing gas from the gas supply source to this electrode body. The processing gas was supplied through a large number of holes provided in the electric scraper between the electrodes on which the semiconductor wafer was provided.

(i[] to be solved by the invention) However, in the structure in which the processing gas is supplied between each electrode as described above, even if the electrode body connected to the gas supply source is provided with a large number of holes, the gas supply A large amount of the processing gas from the pipe flows out from the hole in the electrode body adjacent to the gas supply pipe.
The amount of gas flowing out decreased as the distance from the gas supply pipe increased.

For this reason, the etching rate of the semiconductor wafer placed on the counter electrode is also affected by the amount of gas flowing out, resulting in the problem that the etching rate differs at each position on the wafer, making it impossible to perform uniform etching. Ta.

This invention was made in response to the above-mentioned problems, and it is possible to uniformly supply processing gas between the electrodes on which the substrate to be processed is installed, thereby making it possible to carry out uniform etching processing, which in turn improves yield. The present invention provides an etching device that contributes to this.

[Structure of the invention]

(Means for Solving the Problems) This invention supplies a processing gas from a processing gas supply section into an airtight container, and provides a substrate to be processed on one side facing each other.
Applying power between the electrodes to convert the processing gas into plasma,
In an apparatus for etching a substrate to be processed with this primed processing gas, at least two gas diffusers having a large number of holes are installed at a predetermined interval in the gas supply section, and the holes of each diffuser are shifted. It is characterized by having been provided.

(Function and effect) By installing at least two gas diffusers having a large number of holes at predetermined intervals in the gas supply section, and by staggering the holes of each diffuser, the substrate to be processed can be placed. Processing gas can be uniformly supplied between the electrodes, which enables uniform etching to be carried out, which has the effect of improving yield.

(Example) Hereinafter, an example in which the present invention apparatus is applied to an etching apparatus in a semiconductor manufacturing process will be described with reference to the drawings.

A device for etching a substrate to be processed, such as a semiconductor wafer (G), for example, a plasma etching device, as shown in FIG. A loader consisting of a transport section (3) for the purpose of etching, and an alignment section (2) for aligning the wafer (2) from this transport section (3), an unloader section, and the wafer (2) aligned by the alignment section (A) for etching. It is composed of a processing section 0 that performs processing, and an operation section 0 that performs operation settings and monitoring of each of these sections.

First, to explain the loader and unloader sections, the storage section (2) has a plurality of wafer cassettes (for example, two) capable of loading and storing a plurality of semiconductor wafers (for example, 25 wafers) at predetermined intervals in the board thickness direction. It is said that it can be stored. This wafer cassette ■ has a corresponding cassette mounting stand (
The cassette mounting table (8) can be moved up and down by an independent elevating mechanism (not shown). Here, it is desirable that the elevating mechanism is always located below the cassette mounting table 0 to prevent dust.

The transport section (2) is provided with an articulated robot 0 that transports wafers (g) between the storage section (2), the alignment section (a), and the processing section (c). This multi-articulation robot (9) is equipped with an arm (10) equipped with a holding mechanism, for example, a vacuum suction mechanism (not shown), and this arm (10) is made of a material to prevent heavy metal contamination of the wafer. For example, it is made of ceramic or quartz. The multi-joint robot (9) is rotatable around the - point and is further movable in the horizontal and axial directions. Further, a vacuum chuck (11) is provided in the alignment section (2) for aligning the wafer (2) transferred from the transfer section (2). This vacuum chuck (11) is composed of a disc-shaped inner chuck and an annular outer chuck that is spaced from the outer circumference of the inner chuck by a predetermined distance. The inner chuck can rotate around the center of the inner chuck and move up and down, and the outer chuck can move in the horizontal and axial directions. Further, a sensor, for example, a transmission type sensor, which detects the outer peripheral edge of the wafer and is movable toward the center of the inner chuck is provided. As described above, the storage section (2), the transport section (2), and the alignment section (A) constitute the loader and unloader sections.

A processing section (2) is configured to process the wafer (2) aligned in the alignment section (A).

This processing section □ includes a processing chamber (12) for etching processing, □ a plurality of chambers capable of transporting wafers (T) while maintaining airtightness, such as an inside load lock chamber (13) and an outside load lock chamber (14). ) are provided, and the outside load lock chamber (13) is connected to an auxiliary chamber (15) that can be used for multiple purposes to perform 1-treatment such as light etching and ashing on the processed ueno λ■. has been done.

The inner load lock chamber (13) is provided with an opening/closing mechanism (16a) on one side of the alignment section (4) side so as to form a wafer (g) entrance. An opening/closing mechanism (16b) that enables isolation from the processing chamber (12) is provided on the opposing surface.

The inside load lock chamber (13) is provided with a handling arm (1'7a) for receiving and transferring wafers (]) from the alignment section (4) to the processing chamber (12). In addition, the above-mentioned outside load lock chamber (1
4) is provided with an opening/closing mechanism (13a) on one side of the processing chamber (12) side that enables isolation from the processing chamber (12), and a preliminary chamber adjacent to this opening/closing mechanism (18a). (
An opening/closing mechanism (18b) is provided on the side surface on the 15) side to allow isolation from the preliminary chamber (15). The outer load lock chamber (14) is provided with a handling arm (17b) for receiving and transferring wafers (1) from the reaction processing chamber (12) to the preliminary chamber (15). Incidentally, a vacuum evacuation mechanism (not shown), such as a rotary pump, is connected to each of the load lock chambers (13) and (14).
Furthermore, a purge mechanism (not shown) capable of introducing an inert gas such as N2 gas is provided. And the above processing chamber (
12) is made of AIi and has a cylindrical interior whose surface is alumite-treated. Below this processing chamber (12), a lower electrode body (20) connected to an elevating mechanism (19) is provided so as to be movable up and down.
Airtightness is maintained by the bellows (21) made of S. This lower electrode body (20) is made of aluminum, for example, and has a flat plate shape with an anodized surface, and the lower electrode body (20) holds the semiconductor wafer ω.
0) has an R-shaped upper surface that slopes from the center to the periphery.

Also, between the lower electrode body (20) and the semiconductor wafer mounting surface, the impedance between the semiconductor wafer (1) and the electrode that holds this semiconductor wafer (20), that is, the lower electrode body (20), is made uniform. As described above, a synthetic polymer film (not shown), such as a heat-resistant polyimide resin having a thickness of about 20 μs to 100 μm, is attached to the semiconductor wafer mounting surface of the lower electrode body (20) with a heat-resistant acrylic resin adhesive. It is being For example, four through holes (not shown) are formed in the lower electrode body (20) in the vertical direction, and a lid pin (2
2) is provided. This lift turbine (22) is
For example, it is made of SUS, and there are four lid bins (22).
The connected plate (23) can be raised and lowered synchronously by driving the raising and lowering mechanism (24). In this case, the above board (2
3) goes up and down = 8 = If the mechanism (24) is not driven, the coil spring (
25), and the tip of the lifter pin (22) is lowered from the surface of the lower electrode body (20). Further, a cooling gas flow conduit is connected to the through hole, and the cooling gas flow conduit is connected to a plurality of, for example, 16, cooling gas flow conduits provided on the surface of the lower electrode body (20) located at the peripheral edge of the semiconductor wafer ω. It communicates with an opening (not shown). A processing chamber (12
) A cooling gas introduction pipe is provided at the bottom and is connected to a cooling gas supply source (not shown).

Furthermore, when applying power to the lower electrode body (20),
In order to improve the uniformity of the etching process, a cooling mechanism, for example, a flow path (26) is provided in the lower electrode body (20), and a pipe (not shown) connected to this flow path (26) is connected. A liquid cooling device (not shown) provides cooling means by circulating a cooling liquid, such as a mixture of antifreeze and water. In the gap from the side of the lower electrode body (20) to the inner surface of the processing chamber (12), 36 exhaust holes (27) with a diameter of, for example, 5 cm are arranged evenly at predetermined angles of, for example, 10° intervals. The exhaust ring (28) provided with the treatment chamber (1
2) An exhaust device, such as a turbo molecular pump and a rotary pump, connected continuously through an exhaust pipe (29) fixed to the side wall and connected to the processing chamber (12) below the exhaust ring (28) and the side wall. etc., the exhaust gas inside the processing chamber (12) can be freely exhausted. In order to place and fix the semiconductor wafer (G) on such a lower electrode body (20), a clamp ring (30) is provided to hold down the wafer (2) when the lower electrode body (20) rises. There is. and,
The wafer (G) comes into contact with this clamp ring (30),
Furthermore, when the electrode body (20) is raised, the clamp ring (30) is configured to rise by a predetermined height, for example, 5 wl, while maintaining a predetermined pressing force. That is, this clamp ring (30) connects, for example, four air cylinders (3
1) is held loose via. The clamp ring (30) is adapted to the diameter of the semiconductor wafer (υ) so that the peripheral edge of the semiconductor wafer (3) comes into contact with the R-formed surface of the lower electrode body (20). ) is made of aluminium, for example, and the surface is anodized, and the alumite treatment provides an insulating alumina coating on the surface.The lower electrode body (
An upper electrode body (32) is provided at the upper part of the processing chamber (12) facing the upper electrode body (20). This upper electrode body (32)
The upper electrode body (32) is made of a conductive material such as aluminum and has an alumite-treated surface, and this upper electrode body (32) is equipped with a cooling means. This cooling means, for example, forms a circulating flow path (33) inside the upper electrode body (32), and connects the processing chamber (12) to the outside through a pipe (not shown) connected to this flow path (33). It is connected to a cooling device (not shown) provided in the cooling device, and has a structure in which a liquid such as a mixture of antifreeze and water is controlled to a predetermined temperature and circulated. An upper electrode (34) made of, for example, amorphous carbon is provided on the lower surface of the upper electrode body (32) in electrical connection with the upper electrode body (32). This upper electrode (34)
There is some space (35) between the upper electrode body (32) and the upper electrode body (32).
) is formed, and a gas supply pipe (36) is formed in this space (35).
) is connected, and this gas supply pipe (36) is connected to the process chamber (12) from a gas supply source (not shown) outside the process chamber (12) through a flow rate regulator (not shown), such as a mass flow controller, to supply a reaction gas, which is a process gas. Gases such as CHF, CF4, etc. and carrier gases such as Ar, He, etc. can be freely supplied to the space (35). Further, in this space (35), a plurality of diffusers such as baffles (37) made of a material such as aluminum having a plurality of holes are provided in order to uniformly diffuse the gas.

The installation of this baffle (37) is as shown in Figure 3.
A first disc-shaped baffle (38) with a diameter of, for example, 40 mm is provided at a connection position between the gas supply pipe (36) and the space (35). And this first baffle (38)
and a second baffle (39) in the form of a disc with a diameter of, for example, 150 mm coaxially with the first baffle (38), with a predetermined interval of, for example, 3n11, and this second baffle (39).
and the second baffle (3 mm) with a predetermined interval, for example, 3
A third baffle (40) in the form of a disc with a diameter of, for example, 150+n+n is coaxially connected to the spacer (35), and a screw (42) is attached to the upper surface of the space (35) while maintaining a predetermined distance with a spacer (41).
It is stopped by In addition, each of the above baffles (38) (3
9) (40) is provided with an opening to form a flow path for the processing gas. This opening is connected to the first baffle (3
8), an opening (38a) with a diameter of, for example, 20nvn.
The second baffle (39) is provided with apertures (39a) having a diameter of, for example, 5 m radially from the center, and the third baffle (40) is provided with apertures (39a) with a diameter of, for example, 2III m.
11 openings (40a,) are provided radially from the center,
The positions of the openings (38a), (39a), and (40a) are shifted so that the processing gas is diffused.

A cooling plate (43) is provided to cool the reaction gas etc. diffused by the baffle (37).
From this cooling plate (43) to the upper electrode (3
The cooling plate (43) and the electrode (34) are arranged so that the processing gas flows into the processing chamber (12) through the
) has a plurality of coaxial holes (44) formed therein. An insulating ring (45) is provided around the upper electrode (34) and the upper electrode body (32), and a shield extends from the lower surface of the insulating ring (45) to the peripheral edge of the lower surface of the upper electrode (40). A ring (46) is provided.

This shield ring (46) is made of an insulator, such as tetrafluoroethylene resin, so as to be able to generate plasma with approximately the same diameter as the substrate to be etched, such as a semiconductor wafer (2). Further, a high frequency power source (47) is provided to apply high-rise square wave power to the upper electrode body (32) and the lower electrode body (20).

In the preliminary room (15), an articulated robot (9
) side is provided with an opening/closing mechanism (15a), and in order to prevent the wafer (1) from flying up due to the pressure difference with the atmosphere when this opening/closing is performed, an exhaust mechanism (not shown) and a purge mechanism for introducing inert gas, etc. are provided. In addition, a mounting table (not shown) for receiving and transferring the wafer (1) is provided so as to be movable up and down. An operating section 0 is provided to monitor the operation settings and wafer processing status of each of the mechanisms configured above. These operating units 0 are composed of a control unit (not shown) consisting of a microcontroller, a part of memory, and an input/output unit, and are configured using software such as C language.

The etching apparatus described above is configured such that an air flow path is formed from the clean room side, which has a higher pressure than the maintenance clean room, to the maintenance clean room side, so as to correspond to the through-the-rahole type.

Next, the operation of the above-mentioned etching apparatus will be explained.

First, a wafer cassette ω containing about 25 wafers is placed on the loading cassette mounting table (8) by an operator or a robot hand, and an empty wafer cassette ■ is placed on the unloading cassette mounting table (8). place Then, the wafer (2) is moved up and down by the lifting mechanism and placed in a predetermined position. At the same time, the articulated robot (9) is moved to the loading wafer cassette ■ side. Then, the arm (10) of the articulated robot 0 is inserted into the lower surface of a desired wafer (g). Then, the cassette mounting table (8) is lowered by a predetermined amount, and the wafer (1) is vacuum-adsorbed by the arm (10). Next, the arm (10) is inserted, transported and placed on the vacuum chuck (11) of the pre-alignment section. Here, the center of the wafer (2) and the orientation flat are aligned.

=15- At this time, an inert gas such as N2 gas is already introduced into the load lock chamber (13) on the inside side to keep it in a pressurized state.

Then, while introducing N2 gas, the opening/closing mechanism (16a) of the inner load lock chamber (13) is opened, and the wafer (υ) aligned by the handling arm (17a) is placed in the inner load lock chamber (13). After that, the opening/closing mechanism (16a) is closed.Then, the inside of this inside load lock chamber (13) is set to a predetermined pressure, for example, 0.1 to 2To
Reduce pressure to rr. At this time, the processing chamber (12) has already been reduced to a predetermined pressure, for example, I.times.10'-4 Torr. In this state, open the opening/closing mechanism (16b) of the inside load lock chamber (13) and open the handling arm (17a).
The wafer (g) is carried into the processing chamber (12). By this carrying-in operation, the lifter pin (22) is moved from the through hole of the lower electrode body (20), for example, by one
Raise at a speed of 2mm/S. As a result of this rise, the wafer (1) is placed on the upper end of each lift turbine (22) and brought to a stopped state. After this, the handling arm (17)
a) is stored in the inside load lock chamber (13), and the opening/closing mechanism (16b) is closed. Then, a predetermined amount of the lower electrode body (20), for example, the lower electrode body (20) in the processing chamber (12) is removed.
The lifting mechanism (19) is driven to raise the wafer (1) as if placing the wafer (2) thereon. Furthermore, in a continuous operation, the lower electrode body (20) is raised at a low speed and brought into contact with the clamp ring (30),
It is raised by a predetermined amount, for example, 5 m, while maintaining a predetermined pressing force. As a result, the lower electrode body (20) and the upper electrode (34
) is set at a predetermined interval, for example, 6 to 20 mm. During the above operation, perform exhaust control and check whether the desired gas flow and exhaust pressure are set. Thereafter, while controlling the exhaust to maintain the inside of the processing chamber (12) at 2 to 3 Torr, reactant gas such as CHF3 gas 11005CC or C
F4 gas 11005CC and carrier gas e.g. He
Gas 110005CC, Ar gas 110003CC, etc. are supplied from a gas supply source through a gas supply pipe (36) to a baffle (37) provided in the space (35) of the upper electrode body (32).
The lower electrode body (20) is provided with a semiconductor wafer (G) through a plurality of holes (44) provided in the upper electrode (34) via a cooling plate (43).
and the upper electrode (34).

That is, the reaction gas from the gas supply pipe (36) is first distributed by the first baffle (38) to the opening (38a) provided in this baffle (38), and this distributed reaction gas is distributed outwardly from the center by a second baffle (39);
The reaction gas from the opening (39a) is further distributed uniformly by the third baffle (40) so as to correspond to the size of the wafer. This uniformly distributed reaction gas then flows out from holes (44) coaxially provided in the cooling plate (43) and the upper electrode (34).

At the same time, a high frequency power source (47) connects the upper electrode (34) and the lower electrode body (20) at a frequency of, for example, 13.56M.
A high frequency power of H2 is applied to convert the reaction gas into plasma, and the semiconductor wafer (υ) is etched, for example, anisotropically, using the reaction gas turned into plasma.

At this time, the upper electrode (34) and the lower electrode body (20) become hot due to the application of high frequency power. Naturally, when the upper electrode (34) reaches a high temperature, thermal expansion occurs. In this case, since the upper electrode (34) is made of amorphous carbon and the upper electrode body (32) in contact with it is made of aluminum, the coefficients of thermal expansion differ and cracks occur. To prevent this crack from occurring, the upper electrode body (
32) A mixture of antifreeze and water is flowed from a cooling means (not shown) connected to the flow path (33) formed inside via piping to indirectly cool the upper electrode (34). are doing. Furthermore, as the temperature of the lower electrode body (20) increases, the temperature of the semiconductor wafer (2) also increases, which may destroy the resist pattern formed on the surface of the semiconductor wafer (0) and cause defects. There is. Therefore, like the upper electrode (34), the lower electrode body (20) is also supplied with antifreeze from a separate cooling device (not shown) connected to the flow path (26) formed in the lower part via piping. It is cooled by flowing water mixed with water. This cooling water is, for example, O~60 to process the semiconductor wafer (G) at a constant temperature.
It is controlled at around °C. In addition, since the semiconductor wafer (2) is also heated by the thermal energy of the plasma, cooling gas flow pipes,
Cooling gas introduction=19- A cooling gas such as helium is supplied to the back surface of the semiconductor wafer from a cooling gas supply source (not shown) through a pipe to cool it. At this time, the opening and the through hole are sealed by setting the semiconductor wafer (1). However, in reality, there is a minute gap between the semiconductor wafer (2) and the surface of the lower electrode body (20) due to surface roughness, etc., and the helium gas is supplied to this gap to remove the semiconductor wafer (20). is being cooled. While maintaining this state, the etching process is performed for a predetermined period of time, for example, 2 minutes. Then, upon completion of this process, the lower electrode body (20) is lowered while exhausting the reaction gas, etc. in the process chamber (12), and the lifter pin (22) is lowered.
) Place the wafer ■ on top. Then, the pressures in the outside load lock chamber (14) and the processing chamber (12) are made equal, and the opening/closing mechanism (18b) is opened. Next, the handling arm (
17b) into the processing chamber (12), lower the lifter pin (22), and move the wafer ■ to the handling arm (
17b) and place it by suction. Then, the handling arm (17b) is stored in the outside load rotor chamber (14), and the opening/closing mechanism (18a) is closed. At this time, the preliminary chamber (15) has already been depressurized to the same extent as the outside load lock chamber (14). Then, the opening/closing mechanism (18b) is opened, and the handling arm (17b) stores the wafer (D) on the mounting table (not shown) in the preliminary chamber (15). is lowered to open the opening/closing mechanism (15a) of the preliminary chamber (15).

Next, the articulated robot (9) is moved to a predetermined position in advance, and the arm (10) of this articulated robot (9) is
) is inserted into the preliminary chamber (15), and the wafer (1) is placed on the arm (1o) by suction. Then, the arm (1o) is carried out and the opening/closing mechanism (15a) of the preliminary chamber (15) is closed. At the same time, the articulated robot (9) is moved to a predetermined position and rotated 180°, and the empty cassette The wafer (υ) is transferred and stored in a predetermined position by the arm (1o).

The series of operations described above is performed on the wafer (2) stored in the cassette (2).

The present invention is not limited to the above embodiments, and the substrate to be processed need not be a semiconductor wafer, but may be any type of substrate such as an LCD substrate used in a screen display device such as a liquid crystal TV. When the substrate to be processed is an LCD'D substrate, since the LCD substrate is usually rectangular, the electrode shape may also be rectangular correspondingly. At this time, if the electrode is rectangular, it is desirable that the diffusion plate or baffle, which is a diffuser for diffusing the reaction gas, also be rectangular. Further, in the above embodiment, an example was explained in which three baffles were provided, but the invention is not limited to this, and the reaction gas supplied concentrated at one location is distributed over the entire surface according to the shape of the substrate to be processed. Any type of plate provided with a plate to evenly distribute the liquid may be used. Further, the size and arrangement of the holes provided in the diffusion plate may be any size, and for example, as shown in FIG. Shift the position of each hole (48) so that the hole (48) in the first sheet is located at the center of the four holes (48) in the second sheet, and place each diffuser plate (49) in a predetermined position. It may be installed in

Furthermore, as shown in FIG. 4 (13), the holes (
51) may be formed in a tapered shape so as to increase in size along the flow path of the reactive gas (52), and the hole provided in the electrode for supplying the reactive gas onto the substrate to be processed may also be formed in a tapered shape. Once formed, the reactant gas is distributed more evenly.

Furthermore, the diffuser is not limited to a baffle, but may be one using a porous material, or anything that can diffuse the reaction gas. It may be provided at an interval that makes contact with the body.

As described above, according to this embodiment, at least two gas diffusers each having a large number of holes are installed at a predetermined interval in the reaction gas supply section, which is a processing gas, and the holes of each diffuser are shifted. By providing this, the processing gas can be uniformly supplied between the respective electrodes where the substrate to be processed is installed, and thereby the substrate to be processed can be uniformly etched, which has the effect of contributing to an improvement in yield.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of an etching apparatus for explaining one embodiment of the apparatus of the present invention, Figure 2 is an explanatory diagram of the configuration of the processing chamber in Figure 1, and Figure 3 is Figure 2. Installation of a diffusion plate in the processing chamber. Explanatory diagram, 4th
This figure is an explanatory diagram of another embodiment of FIG. 3. 1... Semiconductor wafer 5... Processing section 12... Processing chamber 32... Upper electrode body 34... Upper electrode
35...Space 37...Baffle 43...Cooling plate

Claims (1)

[Claims] Processing gas is supplied from a processing gas supply unit into an airtight container, a substrate to be processed is provided on one side facing each other, electric power is applied between the electrodes to convert the processing gas into plasma, and the plasma processing gas An apparatus for etching a substrate to be processed, characterized in that at least two gas diffusers having a large number of holes are installed at a predetermined interval in the gas supply section, and the holes of each diffuser are staggered. Etching equipment.