Atomic layer deposition apparatus and substrate coating method

Abstract

The present invention relates to an atomic layer deposition apparatus and method, the apparatus comprising a reaction chamber (10), an electrode assembly (2) positioned relative to an upper wall (11), a counter electrode (3) positioned opposite to the electrode assembly (2), a reaction zone (15a) formed between the electrode assembly (2) and the counter electrode (3), a precursor supply opening (4) for supplying a precursor to the reaction space (15), a connecting element (14) positioned between the electrode assembly (2) and the upper wall (11), a dielectric layer (5) provided on the inner surface (11a) of the upper wall (11), and a gap (6) formed between the upper surface (2a) of the electrode assembly (2) and the dielectric layer (5) to provide a passage (8) for a blocking gas to prevent the formation of a precursor film.

Description

Technical Field

[0001] The present invention relates to an atomic layer deposition apparatus for continuously treating the surface of a substrate with at least a first precursor and a second precursor according to the principle of atomic layer deposition, and more particularly to an apparatus defined in the opening part of independent claim 1.

[0002] Furthermore, the present invention relates to a method defined in the opening part of independent claim 11 for coating a substrate in a plasma ALD reaction chamber by subjecting the surface of the substrate to a continuous surface reaction of a first precursor and a second precursor according to the principle of atomic layer deposition in the reaction chamber.

Background Art

[0003] In prior art solutions, when depositing a conductive coating in a plasma ALD reaction chamber, the coating is formed not only on the surface to be deposited but also on the walls of the reaction chamber. When the coating is formed between the electrode and the wall of the reaction chamber and connects the two, an electrical short circuit occurs.

Summary of the Invention

[0004] The object of the present invention is to provide an apparatus and a method for solving or at least reducing the drawbacks of the prior art.

[0005] The object of the present invention is achieved by an apparatus and a method characterized by the content described in the independent claims. Preferred embodiments of the present invention are disclosed in the dependent claims.

[0006] The present invention is based on the idea of providing a dielectric layer and a flow of blocking gas flowing in relation to the dielectric layer to prevent film formation between the reaction chamber and the electrode assembly in order to prevent an electrical short circuit.

[0007] According to the present invention, an atomic layer deposition apparatus for continuously processing the surface of a substrate with at least a first precursor and a second precursor according to the principle of atomic layer deposition comprises a reaction chamber having an upper wall, a bottom wall, and at least one side wall, wherein the wall forms a reaction space inside the reaction chamber. The apparatus further comprises an electrode assembly disposed relative to the upper wall, a counter electrode disposed at a distance from the electrode assembly and opposite to the electrode assembly such that a reaction zone is formed between the electrode assembly and the electrode assembly, and a precursor supply opening for supplying a precursor to the reaction space. The apparatus further comprises a connecting element disposed between the electrode assembly and the upper wall so as to connect the electrode assembly to the upper wall of the reaction chamber, a dielectric layer provided on the inner surface of the upper wall of the reaction chamber, a gap formed between the upper surface of the electrode assembly and the dielectric layer on the inner surface of the upper wall of the reaction chamber to provide a flow path for a blocking gas so as not to form a precursor film between the electrode assembly and the reaction chamber, and a gas supply opening opening into the gap to supply a blocking gas from the blocking gas flow path to the gap. The gap extends between the connecting element and the outer circumference of the electrode assembly and opens into the reaction space through the outer circumference of the electrode assembly.

[0008] In other words, the electrode assembly and the counter electrode are spaced apart from each other so that a reaction zone is formed between the electrode assembly and the counter electrode where the reaction occurs during the plasma ALD process. Power is supplied to the electrode assembly, while the counter electrode is the ground electrode. A precursor supply opening provides a flow path for the precursor from the precursor source to the reaction space inside the reaction chamber. The electrode is connected to the upper wall of the reaction chamber by a connecting element, which is positioned between the upper wall of the reaction chamber and the electrode. This creates a gap between the upper wall of the reaction chamber and the electrode. The distance between the upper wall of the reaction chamber and the electrode is preferably only a few millimeters, for example 0.2 to 5 mm, preferably 0.3 to 2 mm, so that the maximum distance between the upper wall of the reaction chamber and the electrode is 5 mm, preferably 2 mm, and the minimum distance between the upper wall of the reaction chamber and the electrode is only 0.2 mm, preferably 0.3 mm. The upper wall comprises a dielectric layer which may be in the form of a dielectric coating or dielectric plate or dielectric sheet or any other dielectric covering covering the upper wall, so that the upper wall is covered with an electrical insulator that prevents charge from flowing through the covering. As a result, the gap formed between the upper wall of the reaction chamber and the electrode assembly is formed between the dielectric layer on the upper wall of the reaction chamber and the upper surface of the electrode assembly. A gas supply opening opens into the gap and thus provides a path for blocking gas from the blocking gas channel to the gap. The gas supply opening, which provides a path for blocking gas to the gap, together with the dielectric layer, prevents precursor gas from entering the gap from the reaction zone and, in particular, prevents the formation of a coating on the connection between the upper wall of the reaction chamber and the electrode assembly, thereby preventing the possibility of an electrical short circuit. The gap provided between the upper surface of the electrode assembly and the dielectric layer provided on the inner surface of the upper wall of the reaction chamber extends parallel to the upper surface of the electrode assembly between the connecting element and the outer periphery of the electrode assembly. The connecting element may include additional structures that shorten the length of the gap, and as a result, the gap extends from the outer periphery of the electrode assembly to the structure of the connecting element that forms the other end of the gap relative to the outer periphery of the electrode assembly and possibly the structure surrounding the connecting element.The outer periphery of the electrode assembly is the edge of the electrode assembly closest to at least one side wall of the reaction chamber. In other words, the outer periphery of the electrode assembly forms the edge of the upper surface of the electrode assembly. The gap opens to the reaction space through the outer periphery of the electrode assembly in such a way that the electrode assembly is positioned away from at least one side wall of the reaction chamber, thereby forming a flow path for blocking gas from the gap to the reaction space between at least one side wall and the electrode assembly. The electrode assembly has an outer periphery, i.e., the flow path for blocking gas is formed between at least one side wall of the reaction chamber and the outer periphery of the electrode assembly.

[0009] According to the present invention, the blocking gas channel is arranged to extend inside the electrode assembly such that a gas supply opening for supplying blocking gas from the blocking gas channel to the gap is provided on the upper surface of the electrode assembly.

[0010] In other words, the gas supply opening is located on the top surface of the electrode assembly and opens through the top surface of the electrode assembly to the gap, and the blocking gas channel extends inside the electrode assembly so that the blocking gas channel communicates with a gas source outside the reaction chamber. The gas source can be an inert gas as the blocking gas or a precursor gas as the blocking gas.

[0011] According to the present invention, the blocking gas channel is arranged to extend through the upper wall of the reaction chamber such that a gas supply opening for supplying blocking gas from the blocking gas channel to the gap is provided on the inner surface of the upper wall of the reaction chamber having a dielectric layer.

[0012] In other words, the gas supply opening is located on the inner surface of the upper wall of the reaction chamber, penetrates the upper wall of the reaction chamber and opens into the gap, and the blocking gas channel extends inside the upper wall of the reaction chamber so that the blocking gas channel communicates with a gas source outside the reaction chamber. The gas source can provide an inert gas as the blocking gas or a precursor gas as the blocking gas. In a preferred embodiment of the present invention, a vacuum chamber surrounds the reaction chamber, the blocking gas channel extends through the upper wall of the reaction chamber between the gap and the vacuum chamber, and the blocking gas supplied through the blocking gas channel is an inert gas in the vacuum chamber.

[0013] According to the present invention, the gas supply opening is positioned closer to the connecting element than to the outer circumference of the electrode assembly.

[0014] In other words, the gas supply opening that provides a blocking gas flow path from the blocking gas flow path to the gap is located on the upper surface of the electrode assembly, preferably adjacent to the connecting element on the upper surface of the electrode assembly, rather than on the outer circumference of the electrode assembly.

[0015] According to the present invention, the electrode assembly comprises an upper surface facing the upper wall of the reaction chamber, a lower surface facing the bottom wall of the reaction chamber, and an outer peripheral surface facing at least one side wall of the reaction chamber. The electrode assembly is positioned at a distance from at least one side wall such that the flow path extends from a first gap, past the outer periphery of the upper surface of the electrode assembly, to a second gap between the outer peripheral surface of the electrode assembly and at least one side wall of the reaction chamber.

[0016] In other words, the blocking gas flow path extends into the reaction chamber from the gas supply opening through the gap between the upper surface of the electrode assembly and the inner surface of the upper wall of the reaction chamber, which comprises the dielectric layer, i.e., along a first gap extending parallel to the upper surface of the electrode assembly, to the gap between at least one side wall of the reaction chamber and the outer surface of the electrode assembly, i.e., to a second gap extending parallel to at least one side wall of the reaction chamber. Thus, the first and second gaps extend in a direction transverse to each other.

[0017] According to the present invention, the dielectric layer is arranged to extend from the inner surface of the upper wall of the reaction chamber to at least one side wall of the reaction chamber.

[0018] In other words, the dielectric layer covers the inner surface of the upper wall of the reaction chamber and extends to the inner surface of at least one side wall of the reaction chamber. In a preferred embodiment of the present invention, there is no discontinuity in the dielectric layer when moving from the upper wall to at least one side wall. The dielectric layer is preferably provided on at least one side wall of the reaction chamber in a region facing the outer circumferential surface of the electrode assembly.

[0019] According to the present invention, the dielectric layer is arranged to extend from the inner surface of the upper wall of the reaction chamber to at least one side wall of the reaction chamber, such that a second gap is formed between the dielectric layer and the outer surface of the electrode assembly on at least one side wall of the reaction chamber.

[0020] In other words, the dielectric layer covers the inner surface of the upper wall of the reaction chamber and extends to the inner surface of at least one side wall of the reaction chamber. In a preferred embodiment of the present invention, there is no discontinuity in the dielectric layer when moving from the upper wall to at least one side wall. The dielectric layer is preferably provided on at least one side wall of the reaction chamber in a region facing the outer surface of the electrode assembly, such that the dielectric layer is provided along the region of the second gap.

[0021] According to the present invention, the apparatus further comprises a shower head for supplying a precursor to a reaction space, the shower head comprising a precursor supply opening and an electrode assembly.

[0022] In other words, the apparatus comprises a showerhead, which is a nozzle that supplies a precursor to the reaction space within the reaction chamber through a plurality of precursor supply openings. Thus, the precursor supply openings are provided on the showerhead. The showerhead has a supply surface having the precursor supply openings. The supply surface faces the counter electrode such that a reaction zone is formed between the supply surface of the showerhead and the counter electrode. Furthermore, the showerhead comprises an electrode assembly as part of the showerhead. The electrode assembly forms the upper part of the showerhead, with the upper surface of the electrode assembly facing the upper wall of the reaction chamber.

[0023] According to the present invention, the apparatus further comprises a blocking gas channel, the blocking gas channel having a gas supply opening that opens into a gap to supply blocking gas from the blocking gas channel to the gap, and the blocking gas channel is arranged to extend inside the shower head such that the gas supply opening for supplying blocking gas from the blocking gas channel to the gap is provided on the upper surface of the electrode assembly.

[0024] In other words, the blocking gas channel extends inside the showerhead to supply the blocking gas from a gas source into the gap between the top surface of the electrode assembly and the dielectric layer on the inner surface of the upper wall of the reaction chamber. The blocking gas channel extending inside the showerhead may be a separate gas channel from the precursor supply channel that extends inside the showerhead and communicates with the reaction space through a precursor supply opening to supply the precursor from a precursor source to the reaction zone, or the blocking gas channel may be part of the precursor supply channel that supplies the precursor from a precursor source outside the reaction chamber to both the reaction zone and the gap. The precursor supplied to the gap does not undergo film formation in the reaction zone, as there is no plasma or one or more co-reacting precursors.

[0025] According to the present invention, the apparatus further comprises a vacuum chamber, and the reaction chamber is disposed inside the vacuum chamber.

[0026] In other words, the vacuum chamber surrounds the reaction chamber.

[0027] According to the present invention, a method for coating a substrate in a plasma ALD reaction chamber, the method comprising subjecting the surface of the substrate to successive surface reactions of a first precursor and a second precursor in the reaction chamber according to the principle of atomic layer deposition. In the method, the reaction chamber comprises an upper wall, a bottom wall, and at least one side wall, these walls forming a reaction space within the reaction chamber. Further, the reaction chamber comprises an electrode assembly disposed in relation to the upper wall, a counter electrode disposed on the opposite side of the electrode assembly at a distance from the electrode assembly, a reaction zone provided between the electrode assembly and the counter electrode, and a precursor supply opening for supplying a precursor to the reaction zone. The method includes disposing the substrate in the reaction zone, supplying a blocking gas from a blocking gas flow path through a gas supply opening into a gap formed between the upper surface of the electrode assembly and a dielectric layer provided on the inner surface of the upper wall, supplying a precursor from a precursor gas source through the precursor supply opening to the reaction zone, guiding the blocking gas along the gap towards the reaction zone to prevent the precursor from entering the gap, and generating a plasma discharge in the reaction zone with the electrode assembly.

[0028] In other words, the method includes the step of supplying a blocking gas from a blocking gas flow path through a gas supply opening into a gap formed between the inner surface of the upper wall of a reaction chamber having a dielectric layer and the upper surface of an electrode assembly. The method further includes the step of supplying a precursor from a precursor source through a precursor supply opening into a reaction zone, where the precursor supply opening may be provided, for example, on at least one side wall of the reaction chamber such that the precursor is supplied towards the opposing side wall, or may be provided in a showerhead arranged in relation to the upper wall of the reaction chamber such that the precursor is supplied towards the opposing electrode. The method further includes the step of guiding the blocking gas along the gap, i.e., in a direction parallel to the upper wall of the reaction chamber having a dielectric layer, or alternatively, or in addition, in a direction parallel to the upper surface of the electrode assembly. The method further includes the step of guiding the blocking gas into the reaction zone, i.e., along the gap and further at the end of the gap parallel to the surface of at least one side wall of the reaction chamber, towards the reaction zone located on the opposite side of the upper surface of the electrode assembly, meaning supplying the blocking gas.

[0029] According to the present invention, the method further includes supplying a precursor from a precursor gas source to a showerhead having a precursor supply opening and further supplying the precursor from the showerhead through the precursor supply opening into the reaction zone.

[0030] [[ID=⑧]]In other words, the step of supplying a precursor includes supplying the precursor through a showerhead provided with a precursor supply opening. The showerhead preferably comprises a plurality of precursor supply openings. The method includes supplying the precursor from the showerhead through the precursor supply opening into a reaction zone provided between the showerhead and an opposing electrode, and the showerhead comprises an electrode assembly.

[0031] According to the present invention, the method further includes supplying a precursor from a precursor source to a gap as a blocking gas through a blocking gas channel, and further supplying the precursor from the precursor source to a reaction zone as a plasma gas through a precursor supply opening.

[0032] In other words, this method includes the step of supplying a blocking gas precursor to the gap and supplying the same precursor to the reaction zone through a precursor supply opening. The precursor supplied to the reaction zone is activated by the plasma in the reaction zone and forms a film on the surface of the substrate, but the precursor supplied to the gap is not activated by the plasma when supplied to the gap, and therefore does not form a film on the inner surface of the upper wall of the reaction chamber or on the upper surface of the electrode assembly.

[0033] According to the present invention, the method further includes supplying an inert gas as a blocking gas from an inert gas source to a gap through a blocking gas flow path.

[0034] In other words, this method includes the step of supplying a blocking gas into the gap, wherein the blocking gas is nitrogen gas (N 2 ) are inert gases.

[0035] According to the present invention, the reaction chamber is placed inside a vacuum chamber, and the method further includes supplying an inert gas from the vacuum chamber through the upper wall of the reaction chamber to the gap.

[0036] In other words, the method includes the step of supplying an inert gas to the gap from a vacuum chamber surrounding the reaction chamber, via a blocking gas channel that extends through the upper wall of the reaction chamber. The inert gas is an inert gas that spreads within the vacuum chamber.

[0037] According to the present invention, the method further includes guiding the blocking gas outward from the outer periphery of the upper surface of the electrode assembly along the gap, and further guiding it to the reaction zone along the path between the outer periphery of the electrode assembly and at least one side wall of the reaction chamber.

[0038] In other words, the method includes the step of guiding the blocking gas along the gap parallel to the upper wall of the reaction chamber to the outer circumference of the upper surface of the electrode assembly, and further guiding it along the surface of at least one side wall to the reaction zone. This means that the method includes supplying the blocking gas along the upper wall of the reaction chamber to the corner region of the reaction chamber, and from there supplying it along the surface of at least one side wall of the reaction chamber, which protects the surface of the reaction chamber from film formation by the active precursor arriving from the reaction zone.

[0039] According to the present invention, this method is carried out using the apparatus described above.

[0040] An advantage of the present invention is that the dielectric layer and the blocking gas together prevent film formation on the surface of the reaction chamber and prevent the possibility of electrical short circuits between the electrode assembly and the reaction chamber caused by conductive coatings. [Brief explanation of the drawing]

[0041] The present invention will be described in detail by specific embodiments with reference to the accompanying drawings.

[0042] [Figure 1] This shows the apparatus according to the present invention. [Figure 2] This shows the apparatus according to the present invention as viewed from above. [Figure 3] This shows an apparatus according to the present invention, which also has a dielectric layer on the side wall. [Figure 4] This shows an apparatus according to the present invention having a gas supply opening in the upper wall. [Figure 5] This shows an apparatus according to the present invention, which has a shower head and a dielectric layer on the side wall. [Figure 6] This shows an apparatus according to the present invention that has a shower head. [Figure 7] The present invention is shown having different geometric shapes. [Modes for carrying out the invention]

[0043] Figure 1 shows an apparatus 1 according to the present invention, having a reaction chamber 10 and a vacuum chamber 20 surrounding the reaction chamber 10. The reaction chamber 10 has an upper wall 11, a bottom wall 12, and at least one side wall 13, these walls forming a reaction space 15 inside the reaction chamber 10. The apparatus 1 further comprises an electrode assembly 2 positioned relative to the upper wall 11. The electrode assembly 2 has an upper surface 2a facing the upper wall 11 of the reaction chamber 10, an outer circumference 22 having an outer peripheral surface 2b facing at least one side wall 13 of the reaction chamber 10, and a lower surface 2c facing the bottom wall 12. The reaction chamber 10 further comprises a counter electrode 3 positioned at a distance from the electrode assembly 2 and opposite to the electrode assembly 2, forming a reaction zone 15a between the electrode assembly 2 and the counter electrode 3. The counter electrode 3 is preferably provided relative to the bottom wall 12. The reaction chamber 10 further comprises a precursor supply opening 4 for supplying a precursor to the reaction space 15, particularly the reaction zone 15a. Apparatus 1 further comprises a connecting element 14 for connecting the electrode assembly 2 to the upper wall 11 of the reaction chamber 10. Furthermore, apparatus 1 comprises a dielectric layer 5 disposed on the inner surface 11a of the upper wall 11 of the reaction chamber 10. A gap 6 is formed between the upper wall 11 of the reaction chamber 10 and the electrode assembly 2. In other words, the gap 6 is formed between the dielectric layer 5 provided on the inner surface 11a of the upper wall 11 and the upper surface 2a of the electrode assembly 2. All of the above applies to the apparatus shown in all of Figures 1 to 6.

[0044] Figure 1 further shows a gas supply opening 7 formed on the upper surface 2a of the electrode assembly 2, which opens into the gap 6 to supply blocking gas from the blocking gas channel 17 to the gap 6. The blocking gas channel 17 extends inside the electrode assembly 2 and communicates with a gas source outside the reaction chamber 10. The blocking gas channel 17 can extend from inside the electrode assembly 2 through the connecting element 14 and further outside the reaction chamber 10 and the vacuum chamber 20 to the gas source. The blocking gas channel 8 supplied from the gas supply opening 7 on the upper surface 2a of the electrode assembly 2 extends along the gap 6 parallel to the dielectric layer 5 to the outer circumference 22 of the electrode assembly 2, and extends along the outer circumference 2b of the electrode assembly 2 to the reaction zone 15. In Figure 1, the precursor supply opening 4 is located on the side wall 13 of the reaction chamber 10.

[0045] Figure 2 shows the apparatus 1 shown in Figure 1 as viewed from above, along line AA as seen in Figure 1. In this example, apparatus 1 has a circular geometric shape with a vacuum chamber 20 surrounding a reaction chamber 10, and the reaction chamber 10 has side walls 13. A connecting element 14 forms a connection to the upper wall (not shown in this figure) of the reaction chamber 10. The electrode assembly 2 has a top surface 2a, and the blocking gas flows along the top surface 2a toward the outer circumference 22 of the electrode assembly 2, past the outer circumference 22 of the electrode assembly 2, and into a second gap between at least one side wall 13 and the outer surface 2b of the electrode assembly 2. In this example, the gas supply opening 7 is provided on the top surface 2a of the electrode assembly 2 adjacent to the connecting element 14. However, it is always preferable that the gas supply opening 7 is located closer to the end of the connecting element or gap 6 than to the outer circumference 22 of the electrode assembly 2.

[0046] Figure 3 shows the same structure as the apparatus 1 shown in Figure 1, except that the dielectric layer 5 also extends to at least one side wall 13 of the reaction chamber 10. Preferably, the dielectric layer 5 extends along the length of the second gap 9 between the side wall 13 and the outer peripheral surface 2b of the electrode assembly 2. In Figure 3, the precursor supply opening 4 is located in the side wall 13 of the reaction chamber 10.

[0047] Figure 4 shows the same structure as apparatus 1 shown in Figure 1, except that the gas supply opening 7 is located on the upper wall 11 of the reaction chamber 10, and the blocking gas flow path 17 extends from the vacuum chamber 20 to the gap 6 through the upper wall 11 of the reaction chamber 10. The gas supply opening 7 is located closer to the connecting element 14 than the outer circumference 22 of the electrode assembly 2. In Figure 4, the precursor supply opening 4 is located on the side wall 13 of the reaction chamber 10.

[0048] Figure 5 shows apparatus 1 according to the present invention having the same structural components as those described in relation to Figure 1 and stated to apply to all figures. The apparatus shown in Figure 5 further comprises a shower head 24, which has a precursor supply opening 4 for supplying a precursor to a reaction zone 15 provided between the shower head 24 and the counter electrode 3. Furthermore, the shower head 24 comprises an electrode assembly 2 having an upper surface 2a, an outer peripheral surface 2b, and a lower surface 2c. A gas supply opening 7 is formed on the upper surface 2a of the electrode assembly 2, and the gas supply opening 7 opens into the gap 6 to supply blocking gas from a blocking gas flow path 17 to the gap 6. Since the electrode assembly 2 is part of the shower head 24, the blocking gas flow path 17 extends into the interior of the shower head 24 and communicates with gas sources outside the reaction chamber 10 and outside the vacuum chamber 20. The blocking gas channel 17 can extend from inside the electrode assembly 2 within the showerhead 24, through the connecting element 14, and further to the outside of the reaction chamber 10 and the outside of the vacuum chamber 20 to the gas source. Alternatively, the blocking gas channel 17 may be part of a precursor channel that supplies the precursor to the showerhead 24 and to the reaction zone 15 through the precursor supply opening 4. Thus, the gas source outside the vacuum chamber 20 is a precursor gas source that supplies the precursor to the reaction zone 15 and also supplies it to the gap 6 as a blocking gas. The blocking gas channel 8, supplied from the gas supply opening 7 on the upper surface 2a of the electrode assembly 2 within the showerhead 24, extends along the gap 6 parallel to the dielectric layer 5 to the outer circumference 22 of the electrode assembly 2, and extends along the outer circumference 2b of the electrode assembly 2 to the reaction zone 15. At least one side wall 13 of the reaction chamber 10 further comprises a dielectric layer 5 along a second gap 9 between the side wall 13 and the outer circumference 2b of the electrode assembly 2 in the showerhead 24.

[0049] Figure 6 shows apparatus 1 according to the present invention having the same structural components as those described in relation to Figure 1 and stated to apply to all figures. The apparatus shown in Figure 6 further comprises a shower head 24, as described in relation to Figure 5, the shower head 24 having a precursor supply opening 4 for supplying a precursor to a reaction zone 15 provided between the shower head 24 and the counter electrode 3. Furthermore, the shower head 24 comprises an electrode assembly 2 having an upper surface 2a, an outer peripheral surface 2b, and a lower surface 2c. A gas supply opening 7 is formed on the upper surface 2a of the electrode assembly 2, and the gas supply opening 7 opens into the gap 6 to supply blocking gas from a blocking gas passage 17 to the gap 6. Since the electrode assembly 2 is part of the shower head 24, the blocking gas passage 17 extends into the interior of the shower head 24 and communicates with gas sources outside the reaction chamber 10 and outside the vacuum chamber 20. The blocking gas channel 17 can extend from inside the electrode assembly 2 within the showerhead 24, through the connecting element 14, and further to the outside of the reaction chamber 10 and the outside of the vacuum chamber 20 to the gas source. Alternatively, the blocking gas channel 17 may be part of a precursor channel that supplies the precursor to the showerhead 24 and to the reaction zone 15 through the precursor supply opening 4. In this case, the gas source outside the vacuum chamber 20 is a precursor gas source that supplies the precursor to the reaction zone 15 and also supplies it to the gap 6 as a blocking gas. The blocking gas channel 8, supplied from the gas supply opening 7 on the upper surface 2a of the electrode assembly 2 within the showerhead 24, extends along the gap 6 parallel to the dielectric layer 5 to the outer circumference 22 of the electrode assembly 2, and then extends along the outer circumference 2b of the electrode assembly 2 to the reaction zone 15.

[0050] Figure 7 shows a cross-section of the apparatus 1 according to the present invention, which is presented above but has a different geometric shape, from the same point as shown in Figure 2. In this example, apparatus 1 has a rectangular geometric shape with a reaction chamber 10 surrounded by a vacuum chamber 20, and the reaction chamber 10 has side walls 13. A connecting element 14 forms a connection to the upper wall of the reaction chamber 10 (not shown in this figure). The electrode assembly 2 has a top surface 2a, and the blocking gas flows along the top surface 2a toward the outer periphery 22 of the electrode assembly 2, past the outer periphery 22 of the electrode assembly 2, into a second gap 9 between at least one side wall 13 and the outer periphery surface 2b of the electrode assembly 2 (the outer periphery surface is not shown in this figure, but the outer periphery 22 is shown). In this example, a gas supply opening 7 is provided on the top surface 2a of the electrode assembly 2 adjacent to the connecting element 14. The blocking gas is supplied from the gas supply opening 7 and flows along the gap 6 in the flow path 8 toward the outer periphery 22 of the electrode assembly 2. The flow path 8 extends past the outer circumference 22 of the electrode assembly 2 and reaches a second gap 9 at the outer circumference 22 of the electrode assembly 2, which extends along the outer surface 2b of the electrode assembly 2 and the side wall 13 of the reaction chamber 10.

[0051] The present invention has been described above with reference to the examples shown in the figures. However, the present invention is by no means limited to the above embodiments and may vary within the scope of the claims.

Claims

1. An atomic layer deposition apparatus (1) for continuously processing the surface of a substrate with at least a first precursor and a second precursor according to the principle of atomic layer deposition, The reaction chamber (10) has an upper wall (11), a bottom wall (12), and at least one side wall (13), and the walls (11, 12, 13) form a reaction space (15) inside the reaction chamber (10), An electrode assembly (2) positioned in relation to the upper wall (11), A counter electrode (3) is positioned at a distance from the electrode assembly (2) and facing the electrode assembly (2) such that a reaction zone (15a) is formed between the electrode assembly (2) and the counter electrode (3), A precursor supply opening (4) for supplying a precursor to the reaction space (15), Includes, A connecting element (14) is positioned between the electrode assembly (2) and the upper wall (11) of the reaction chamber (10), wherein the connecting element (14) connects the electrode assembly (2) to the upper wall (11) through the connecting element (14), A dielectric layer (5) is provided on the inner surface (11a) of the upper wall (11) of the reaction chamber (10), In order to provide a blocking gas flow path (8) so as not to form a precursor film between the electrode assembly (2) and the reaction chamber (10), a gap (6) is formed between the upper surface (2a) of the electrode assembly (2) and the dielectric layer (5) on the inner surface (11a) of the upper wall (11) of the reaction chamber (10), extending between the connecting element (14) and the outer circumference (22) of the electrode assembly (2), and opening to the reaction space (15) through the outer circumference (22) of the electrode assembly, In order to supply blocking gas from the blocking gas passage (17) to the gap (6), a gas supply opening (7) is provided that opens into the gap (6), Atomic layer deposition apparatus (1) further comprising

2. The atomic layer deposition apparatus (1) according to claim 1, characterized in that the blocking gas channel (17) is arranged to extend inside the electrode assembly (2) such that the gas supply opening (7) for supplying the blocking gas from the blocking gas channel (17) to the gap (6) is provided on the upper surface (2a) of the electrode assembly (2).

3. The atomic layer deposition apparatus (1) according to claim 1, characterized in that the blocking gas channel (17) is arranged to extend through the upper wall (11) of the reaction chamber (10) such that the gas supply opening (7) for supplying the blocking gas from the blocking gas channel (17) to the gap (6) is provided on the inner surface (11a) of the upper wall (11) of the reaction chamber (10) having the dielectric layer (5).

4. The atomic layer deposition apparatus (1) according to any one of claims 1 to 3, characterized in that the gas supply opening (7) is positioned closer to the connecting element (14) than to the outer circumference (22) of the electrode assembly (2).

5. The electrode assembly (2) includes an upper surface (2a) facing the upper wall (11) of the reaction chamber (10), a lower surface (2c) facing the bottom wall (12) of the reaction chamber (10), and an outer peripheral surface (2b) facing at least one side wall (13) of the reaction chamber (10), The atomic layer deposition apparatus (1) according to any one of claims 1 to 4, characterized in that the electrode assembly (2) is positioned at a distance from the at least one side wall (13) such that the flow path (8) extends from the first gap (6) past the outer circumference (22) of the upper surface (2a) of the electrode assembly (2) to the second gap (9) between the outer circumference (2b) of the electrode assembly (2) and the at least one side wall (13) of the reaction chamber (10).

6. The atomic layer deposition apparatus (1) according to any one of claims 1 to 5, characterized in that the dielectric layer (5) is arranged to extend from the inner surface (11a) of the upper wall (11) of the reaction chamber (10) to the at least one side wall (13) of the reaction chamber (10).

7. The atomic layer deposition apparatus (1) according to claim 5, characterized in that the dielectric layer (5) is arranged to extend from the inner surface (11a) of the upper wall (11) of the reaction chamber (10) to the at least one side wall (13) of the reaction chamber (10) such that the second gap (9) is formed between the dielectric layer (5) and the outer peripheral surface (2b) of the electrode assembly (2) on the at least one side wall (13) of the reaction chamber (10).

8. The atomic layer deposition apparatus (1) according to any one of claims 1 to 5, further comprising a shower head (24) for supplying a precursor to the reaction space (15), wherein the shower head (24) includes the precursor supply opening (4) and the electrode assembly (2).

9. The atomic layer deposition apparatus (1) according to claim 8, further comprising a blocking gas channel (17), the blocking gas channel (17) having a gas supply opening (7) that opens into the gap (6) for supplying blocking gas from the blocking gas channel (17) to the gap (6), and the blocking gas channel (17) is arranged to extend inside the shower head (24) such that the gas supply opening (7) for supplying blocking gas from the blocking gas channel (17) to the gap (6) is provided on the upper surface (2a) of the electrode assembly (2).

10. The atomic layer deposition apparatus (1) according to any one of claims 1 to 9, further comprising a vacuum chamber (20), wherein the reaction chamber (10) is located inside the vacuum chamber (20).

11. A method for coating a substrate in a plasma ALD reaction chamber (10) by subjecting the surface of the substrate to a continuous surface reaction of a first precursor and a second precursor in accordance with the principle of atomic layer deposition within the reaction chamber (10), The reaction chamber (10) includes an upper wall (11), a bottom wall (12), and at least one side wall (13), the walls (11, 12, 13) forming a reaction space (15) inside the reaction chamber (10), the reaction chamber (10) further includes an electrode assembly (2) positioned relative to the upper wall (11), a counter electrode (3) positioned at a distance from and opposite to the electrode assembly (2), a reaction zone (15a) provided between the electrode assembly (2) and the counter electrode (3), and a precursor supply opening (4) for supplying the precursor to the reaction zone (15a), The aforementioned method, The substrate is placed within the reaction zone (15a), The blocking gas is supplied from the blocking gas flow path (17) through the gas supply opening (7) to the gap (6) formed between the upper surface (2a) of the electrode assembly (2) and the dielectric layer (5) provided on the inner surface (11a) of the upper wall (11), The precursor is supplied from the precursor gas source through the precursor supply opening (4) to the reaction zone (15a), In order to prevent the precursor from entering the gap (6), the blocking gas is guided along the gap (6) to the reaction zone (15a), The electrode assembly (2) generates a plasma discharge to the reaction zone (15a), A method for processing a substrate, characterized by including the following:

12. A method for processing a substrate according to claim 11, further comprising supplying a precursor from a precursor gas source to a shower head (24) having the precursor supply opening (4), and further supplying the precursor from the shower head (24) to the reaction zone (15a) through the precursor supply opening (4).

13. A method for processing a substrate according to claim 11 or 12, further comprising supplying the precursor from the precursor source to the gap (6) as the blocking gas through the blocking gas flow path (17), and further supplying the precursor from the precursor source to the reaction zone (15a) as a plasma gas through the precursor supply opening (4).

14. The method for processing a substrate according to claim 12, further comprising supplying an inert gas from an inert gas source to the gap (6) as the blocking gas through the blocking gas flow path (17).

15. The reaction chamber (10) is located inside the vacuum chamber (20). The aforementioned method, The method for processing a substrate according to claim 14, further comprising supplying an inert gas from the vacuum chamber (20) to the gap (6) through the upper wall (11) of the reaction chamber (10).

16. A method for processing a substrate according to 14, further comprising guiding the blocking gas outward from the outer periphery of the upper surface (2a) of the electrode assembly (2) along the gap (6), and further guiding it to the reaction zone (15a) along a path between the outer periphery (2b) of the electrode assembly (2) and the at least one side wall (13) of the reaction chamber (10).

17. A method for processing a substrate according to any one of claims 11 to 16, characterized by being performed using the apparatus according to any one of claims 1 to 10.

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