NL2025783B1

NL2025783B1 - Atomic layer deposition head unit and method

Info

Publication number: NL2025783B1
Application number: NL2025783A
Authority: NL
Inventors: Maurice Hemerik Marcel; Adrianus Elizabeth Van De Velden Marinus; Antonius Franciscus Kremers Erik
Original assignee: Sald Ip B V
Priority date: 2020-06-08
Filing date: 2020-06-08
Publication date: 2022-01-28
Also published as: WO2021251821A1; EP4162095A1

Abstract

A method and head unit for atomic layer deposition, ALD. The head unit has an output face including a ﬁrst elongate feed slit for outputting a ﬁrst process gas therethrough towards a substrate and a second elongate feed slit for outputting a second process gas therethrough towards a substrate. The head unit further has at least a first and a second elongate purge slit in the output face between the ﬁrst elongate feed slit and the second elongate feed sit for outputting a purge gas therethrough towards the substrate.

Description

P127039NL00 Title: Atomic layer deposition head unit and method

FIELD OF THE INVENTION The present invention relates to an atomic layer deposition head. More in general, the invention relates to deposition of thin-film materials, such as apparatus for atomic layer deposition.

BACKGROUND TO THE INVENTION Atomic layer deposition, ALD, is a known technique for depositing a thin film of a process material onto a substrate. Advances have been made in recent years in improving ALD. However, certain disadvantages remain.

A first problem often encountered when practicing ALD is that a gas fed from an atomic layer deposition head towards a substrate not only is deposited onto the substrate, but also contaminates the head itself. Therefore, cleaning of the head can be required at a regular basis.

SUMMARY OF THE INVENTION It is an object to provide an atomic layer deposition, ALD, head unit that is less prone to contamination, and optionally can be cleaned more easily. It is also an object to provide an atomic layer deposition head unit that is more convenient in use. More in general it 1s an object to provide an improved ALD head unit. It is also an object to provide a method for depositing a film of material onto a substrate that benefits from such advantages.

According to a first aspect is provided an atomic layer deposition, ALD, head unit having an output face including a first elongate feed slit for outputting a first process gas therethrough towards a substrate and a second elongate feed slit for outputting a second process gas therethrough towards a substrate. The first and second process gasses can be identical or different.

The ALD head unit includes at least a first and a second elongate purge slit in the output face between the first elongate feed slit and the second elongate feed sit for outputting a purge gas therethrough towards the substrate.

Thus, the ALD head unit is arranged for supplying two, e.g. different, process gases to the substrate. The two process gasses can be provided to the substrate alternately or simultaneously. At least two elongate purge slits are positioned between two consecutive elongate feed slits. By providing at least two elongate purge slits between two consecutive elongate feed slits gas separation from one feed slit to the other is greatly improved.

The first and second elongate feed slits allows for depositing a first material, e.g. contained in or formable by the first process gas, and a second material, e.g. contained in or formable by the second process gas, to be deposited along the length of the first and second elongate feed slits, respectively. Preferably, the substrate and the head unit are moved relative to each other, such as in a direction perpendicular to the longitudinal direction of the first and/or second elongate feed slit. Thus, an area on the substrate having one dimension substantially corresponding to the length of the first feed slit and/or second can be covered with a layer of the material.

Optionally, the first elongate purge slit is positioned substantially parallel to the first elongate feed slit, and/or the second elongate purge slit is positioned substantially parallel to the second elongate feed slit. Optionally, the first elongate purge slit circumscribes the first elongate feed slit, and/or the second elongate purge slit circumscribes the second elongate feed slit. This provides the advantage that all around an elongate feed slit the purge gas, can be fed to the substrate. Hence interaction of the process gas from the first elongate feed slit with the second elongate feed slit, and vice versa, is greatly reduced.

Optionally, the output face includes at least one elongate return slit for removing gas from the output face. The elongate return slit can be arranged for sucking gas away from the substrate. The ALD head unit can include an output opening for exhausting gas from the head unit, in communication with the at least one elongate return slit, and a return flow channel extending from the at least one elongate return slit to the output opening.

Optionally, the output face includes a first elongate return slit positioned between the first elongate feed slit and the first elongate purge slit.

The first elongate return slit can be positioned substantially parallel to the first elongate feed slit.

The first elongate return slit can circumscribe the first elongate feed slit.

Optionally, the output face includes a second elongate return slit positioned between the first elongate purge slit and the second elongate purge slit.

The second elongate return slit can be positioned substantially parallel to the first elongate purge slit.

The second elongate return slit can circumscribe the first elongate purge slit.

Optionally, the output face includes a third elongate return slit positioned between the second elongate feed slit and the second elongate purge slit, wherein optionally the third elongate return slit is positioned substantially parallel to the second elongate feed slit, wherein optionally the third elongate return slit circumscribes the second elongate feed slit.

Optionally, the output face includes a fourth elongate return slit positioned between the second elongate purge slit and the first elongate purge slit, wherein optionally the fourth elongate return slit is positioned substantially parallel to the second elongate purge slit, wherein optionally the fourth elongate return slit circumscribes the second elongate purge slit.

The ALD head unit can include a monolithic, e.g. 3D printed, output section including the output face with the first elongate feed slit and the first elongate purge slit.

The monolithic output section can include the at least one elongate return slit.

Optionally, the ALD head unit includes an input section including a first feed opening for inputting the first process gas into the head unit and a second feed opening for inputting the purge gas into the head unit.

The input section can include a first feed flow channel extending from the first feed opening towards the first elongate feed slit, and a second feed flow channel extending from the second feed opening towards the first elongate purge slit. The input section can be monolithic, such as 3D printed.

Optionally, the monolithic input section includes an output opening for exhausting gas from the head, in communication with the at least one elongate return slit and ducts of a return flow channel extending from the at least one elongate return slit to the output opening.

Optionally, the ALD head unit includes a first elongate chamber along the first elongate feed slit, wherein the first elongate chamber includes a flow resistance material. The flow resistance material can be a, e.g. 3D printed, porous material.

Optionally, the ALD head unit includes a second elongate chamber along the second elongate feed slit, wherein the at least one second elongate chamber includes a flow resistance material. The flow resistance material can be a, e.g. 3D printed, porous material.

For proper deposition of a thin layer having a uniform thickness, outflow of the first process gas out of the first elongate feed slit and/or outflow of the second process gas out of the second elongate feed slit is preferably uniform along the lengths of the slits. For creating such uniform outflow, the head includes in the first feed flow channel the first elongate chamber along the first elongate feed slit and/or in the second feed flow channel the second elongate chamber along the second elongate feed slit . Preferably the chamber extends along the entire length of the corresponding slit. Preferably the chamber has a width (perpendicular to the longitudinal direction of the slit) that is wider than a width of the slit. The first elongate chamber can include a flow resistance material, such as a porous material, for creating a back pressure for the first process gas fed into the first chamber. The second elongate chamber can include a flow resistance material, such as a porous material, for creating a back pressure for the second process gas fed into the second chamber. Preferably the flow resistance material extends along the entire length of the respective chamber. Preferably the flow resistance material is in contact with side walls of the respective chamber to prevent gas from bypassing the flow resistance material. The backpressure generated by 5 the flow resistance material aids in making the outflow from the slit uniform along its length. Optionally, the, e.g. 3D printed, porous material is unitary with the output face.

According to a second aspect is provided an atomic layer deposition, ALD, head. The ALD head has an output face including a first elongate feed slit for outputting a first gas therethrough towards a substrate. The first gas can be a first process gas. The first elongate feed slit allows for depositing a first material, e.g. contained in or formable by the first gas, to be deposited along the length of the first elongate feed slit. Preferably, the substrate and the head are moved relative to each other, such asin a direction perpendicular to the longitudinal direction of the first elongate feed slit. Thus, an area on the substrate having one dimension substantially corresponding to the length of the first feed slit can be covered with a layer of the material. The head includes an input face including a first feed opening for inputting the first gas into the head. A first feed flow channel extends from the first feed opening to the first elongate feed slit. Hence, the first gas can be fed from the first feed opening via the first feed flow channel to the first elongate feed slit. The first feed opening can have a compact cross section, such as a circular cross section, for easy connection to a feed line. For proper deposition of a thin layer having a uniform thickness, outflow of the first gas out of the first elongate feed slit is preferably uniform along the length of the slit. For creating such uniform outflow, the head includes in the first feed flow channel a first elongate chamber along the first elongate feed slit. Preferably the chamber extends along the entire length of the slit. Preferably the chamber has a width (perpendicular to the longitudinal direction of the slit) that is wider than a width of the slit. The chamber includes a flow resistance material, such as a porous material, for creating a back pressure for the first gas fed into the chamber. Preferably the flow resistance material extends along the entire length of the chamber. Preferably the flow resistance material is in contact with side walls of the chamber to prevent gas from bypassing the flow resistance material. The backpressure generated by the flow resistance material aids in making the outflow from the slit uniform along its length. The ALD head includes a monolithic output section including the output face and walls of the first elongate chamber. Hence, the output face, the chamber, the first elongate feed slit can be monolithic. The monolithic output section can e.g. be 3D-printed from stainless steel. It has been found that such monolithic output section can easily be cleaned, e.g. in an ultrasonic bath. Also, the monolithic output section provides the advantage that the geometry of the slit can be mechanically more stable than in designs where the slit is formed between separate mechanical parts of the output section.

It has been found that the flow resistance material providing the backpressure can assist in rendering dimensional accuracy of the slit, such as dimensional accuracy of the width of the slit, less important for proper layer deposition. The lesser requirements on dimensional accuracy can enhance the possibilities for monolithically forming the output section, e.g. by 3D printing.

Also, it has been found that using the flow resistance material the feed slit can be chosen having a larger width than when no flow resistance material is used. Such wider width can aid in allowing easy cleaning and/or manufacturing of the output section. The feed slit can e.g. have a width chosen in the interval of 50 pm up to 2000 jum, such as in the interval of 100 pm up to 500 pm, e.g. about 250 pm.

Optionally, the flow resistance material, such as the porous material, is a 3-dimensional, 3D, printed flow resistance material, such as a 3D printed porous material. This provides the advantage that the flow resistance material can easily be manufactured from a material well suited for cleaning, such as stainless steel, or another metal.

Optionally, the 3D printed flow resistance material is unitary with the output face. Thus the flow resistance material can be manufactured as a single unit with the output face. Hence, the output face, the chamber, the first elongate feed slit and the flow resistance material can be monolithic.

The flow resistance material can include holes, channels or pores through an otherwise solid material. The flow resistance material can include plates or platelets with holes or channels in between. The flow resistance material can include globes, cubes or differently shaped objects with interstices therebetween.

The flow resistance material can provide a friction factor for gaseous material passing therethrough that is greater than 1-102, thereby providing back pressure. Preferably, the friction factor is between 1-104 and 1-108, such as between 1-105 and 5106. The back pressure can e.g. promote equalization of pressure where the respective gas exits the feed slit. The friction factor, f, can be represented by /=(FMAxK)), where Fr is the force exerted due to the gas flow, A is the characteristic area of the flow resistance material, and K represents the kinetic energy of the gas flow, as for instance explained in WO2008/085474A2.

Optionally, the ALD head includes a monolithic input section including the input face and ducts of the first feed flow channel extending from the first infeed opening towards the first elongate chamber. The input section can form a monolithic section, wherein the first feed flow channel can transform from a cross section according to the first feed opening to a cross section that connects to the first elongate feed slit.

Optionally, the ALD head includes at least one elongate return slit for removing gas from the output face. The elongate return slit can be arranged for sucking gas away from the substrate. The ALD head can include an output opening for exhausting gas from the head, in communication with the at least one elongate return slit, and a return flow channel extending from the at least one elongate return slit to the output opening.

Optionally the monolithic output section includes the at least one elongate return slit. Hence the first elongate feed slit and the elongate return slit can be part of the same monolithic output section. Optionally, the monolithic input section includes the output opening and ducts of the return flow channel. Hence, the first feed opening and the output opening can form part of the same monolithic input section.

Optionally, the at least one return slit is positioned substantially parallel to the first elongate feed slit. Hence, gas can be removed effectively.

Optionally, the at least one return slit circumscribes the first elongate feed slit. This provides the advantage that all around the first elongate feed slit the gas fed to the substrate, but not deposited into a layer, can be removed. Hence interaction of the ALD head with adjacent ALD heads can be reduced which results in more effective operation and/or less contamination.

Optionally, the ALD head includes at least one second elongate feed slit in the output face for outputting a second gas therethrough towards the substrate. The second gas can be purging gas, such as Na. The ALD head includes a second feed opening for inputting the second gas into the head; and a second feed flow channel extending from the second feed opening to the at least one second elongate feed slit. Hence the ALD head can be used for providing a first gas and a different, second gas to the substrate. The second gas can be a purging gas for reducing influence of the ALD head onto neighboring structures, such as neighbouring ALD heads. Optionally, the head includes in the second feed flow channel a second elongate chamber along the second elongate feed slit, wherein the second elongate chamber includes a 3D printed flow resistance material, such as a porous material, as described in view of the first elongate feed slit.

Optionally, the monolithic output section includes the at least one second elongate feed slit. Hence the first elongate feed slit, the at least one second elongate feed slit, and optionally the elongate return slit, can be part of the same monolithic output section. Optionally, the monolithic input section includes the second feed opening and ducts of the second feed flow channel. Hence, the first feed opening, the second feed opening, and optionally the output opening can form part of the same monolithic input section.

Optionally, the at least one second feed slit is positioned substantially parallel to the first elongate feed slit.

Optionally, the at least one second elongate feed slit circumscribes the first elongate feed slit. This provides the advantage that all around the first elongate feed slit the second gas, such as a purging gas, can be fed to the substrate. Hence interaction of the ALD head with adjacent structures, such as adjacent ALD heads, can be reduced which results in more effective operation and/or less contamination.

Optionally, the at least one elongate return slit is positioned between the first elongate feed slit and the at least one second elongate feed slit. Thus, the return slit can return both the first gas fed by the first elongate feed slit and the second gas fed by the second elongate feed slit.

Optionally, the ALD head includes at least one second elongate return slit for removing gas from the output face. The at least one second elongate return shit can be included in the monolithic output section. The ALD head can include a second output opening for exhausting gas from the head, in communication with the at least one second elongate return slit, and a second return flow channel extending from the at least one second elongate return slit to the output opening. The monolithic input section can include the second output opening and ducts of the second return flow channel.

Optionally, the at least one second return slit is positioned substantially parallel to the first elongate feed slit. Optionally, the at least one second return slit circumscribes the second elongate feed slit. This provides the advantage that all around the second elongate feed slit the second gas, such as the purging gas, can be removed. Hence interaction of the ALD head with adjacent ALD heads can be reduced which results in more effective operation and/or less contamination.

Optionally, the ALD head is monolithic. Hence a simple easy to clean and easy to replace ALD head is provided.

Optionally, the first feed opening and the second feed opening are positioned symmetrically relative to an axis through the center of the head.

This provides the advantage that rotation of the head, e.g. over 180 degrees, around the axis switches the positions of the first and second feed openings, thus allowing simple changing of the gas fed to the first and second feed openings.

Optionally, the first feed opening is positioned such that rotation of the head, e.g. over 180 degrees, around the axis can be used for selectively connecting the first feed opening to a first supply line or to a second supply line, e.g. carrying mutually different gases. Then, the second feed opening may be positioned such that rotation of the head, e.g. over 180 degrees, around the axis connects the second feed opening to a third supply line, e.g.

carrying purge gas, regardless of the rotational position.

According to a third aspect 1s provided An ALD head unit including two or more ALD heads as described hereinabove. The ALD heads can e.g. be mounted side by side. The ALD heads can be mounted such that the respective first elongate feed slits of the ALD heads are positioned substantially parallel.

It will be appreciated that a first gas can be provided to a first ALD head of the ALD head unit, such as a first process gas for depositing a first material, e.g. contained in or formable by the first gas, onto a substrate. A, e.g. different, third gas can be provided to a second ALD head of the ALD head unit, such as a, e.g. different, second process gas for depositing a, e.g.

different, second material, e.g. contained in or formable by the third gas, onto a substrate. A, e.g. different, fourth gas can be provided to a third ALD head of the ALD head unit, and so forth. Optionally, the output sections of the respective ALD heads of the ALD head unit form one unitary part. Hence, an easy to clean ALD head unit can be provided arranged for providing multiple (e.g. different, gases to a substrate, e.g. simultaneously. Optionally, the respective ALD heads of the ALD head unit form one unitary part.

According to a fourth aspect is provided an ALD head unit including a plasma deposition head and at least one ALD head as described hereinabove. Hence, a first gas, such as a first process gas, can be provided to a substrate by a first ALD head, and the substrate can also be treated by a plasma, e.g. simultaneously.

Optionally, an output section of the plasma deposition head forms a unitary part with the output section of the at least one ALD head. Optionally, the plasma deposition head forms a unitary part with the at least one ALD head.

According to a fifth aspect is provided an atomic layer deposition apparatus including one or more ALD heads as described hereinabove or one or more ALD head units as described hereinabove. The apparatus can e.g. include two or more such ALD heads stacked side-by-side.

According to a sixth aspect is provided a method for depositing a film of material onto a substrate, including moving an ALD head or an ALD head unit as described herein and a substrate relative to each other, while flowing a gas including the material through the first elongate feed slit towards the substrate.

According to a seventh aspect is provided a method of manufacturing a) a photovoltaic element, b) a battery, ¢) a display, d) flexible electronics, or e) packaging materials including depositing a film of material,

such as an electrically conducting material, a dielectric material or a barrier material, onto a substrate according to such method for depositing. It will be appreciated that any of the aspects, features and options described in view of the ALD head apply equally to the ALD head unit, the apparatus and the method. It will also be clear that any one or more of the above aspects, features and options can be combined.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention will now be described in detail with reference to the accompanying drawings in which: Figure 1 shows a schematic representation of an example of an atomic layer deposition, ALD, head; Figure 2 shows a schematic representation of an example of an ALD head; Figure 3 shows a schematic representation of an example of an ALD head; Figure 4 shows a schematic representation of an example of an ALD head; Figure 5 shows a schematic representation of an example of an ALD head; Figure 6 shows a schematic representation of an example of an ALD head; Figure 7 shows a schematic representation of an example of an ALD head; Figure 8 shows a schematic representation of an example of an ALD head; Figure 9 shows two views of a schematic representation of an example of an ALD head; Figure 10 shows a schematic representation of an example of an ALD head;

Figure 11 shows a schematic representation of an example of an ALD head; Figure 12 shows a schematic representation of an example of an ALD head; Figure 13 shows a schematic representation of an example of an ALD head unit; Figure 14 shows a schematic representation of an example of an ALD head unit; Figure 15 shows a schematic representation of an example of an ALD head unit; and Figure 16 shows an example of a method.

DETAILED DESCRIPTION Figures 1 and 2 shows a schematic representation of an example of an atomic layer deposition, ALD, head 1. Figure 2 shows a longitudinal cross section of the head 1, Figure 1 a cross section perpendicular to the longitudinal direction of the head 1. The ALD head 1 is arranged for depositing an atomic layer of a material onto a substrate 2. The ALD head 1 includes an output face 4 and an input face 6. The output face 4 includes a first elongate feed slit 8. The input face 6 includes a first feed opening 10. The first feed opening 10 can have a compact cross section, such as a circular cross section, for easy connection to a feed line (not shown). A first feed flow channel 12 extends from the first feed opening 10 to the first elongate feed slit 8. In the first feed flow channel 12 a first elongate chamber 14 is positioned along the first elongate feed slit 8. In this example the chamber 14 extends along the entire length of the first elongate feed slit

8. Here, the chamber 14 has a width, measured perpendicular to the longitudinal direction of the first feed slit 8, that is wider than a width of the first feed slit 8. In this example, the head 1 includes an output section

16. The output section 16 includes the output face 4 and walls 18 of the first elongate chamber 14. Here, the output 16 section 1s monolithic. In this example, the head 1 includes an input section 20. The input section 20 includes the input face 6 and at least a part of the first feed flow channel 12. Here the input section 20 1s monolithic. It 1s possible that the input section 20 forms a unitary part with the output section 16. Hence, the ALD head 1 can be monolithic.

In use a first gas, such as a first process gas is inputted into the first fed opening 10. The first gas travels through the first feed flow channel 12 and through the first elongate chamber 14 to the first elongate feed slit 8.

The a first elongate feed slit 8 is arranged for, in use, outputting the first gas therethrough towards the substrate 2. The first elongate feed slit 8 allows for depositing a first material, e.g. contained in or formable by the first gas, to be deposited onto the substrate 2 along the length of the first elongate feed slit

8.

For proper deposition of a thin layer having a uniform thickness, outflow of the first gas out of the first elongate feed slit 8 is preferably uniform along the length of the slit. For creating such uniform outflow, the head 1 includes in the first elongate chamber 14 along the first elongate feed slit a flow resistance material 22 for creating a back pressure for the first gas fed into the chamber 14. In this example, the flow resistance material 22 is a porous material. Here, the flow resistance material 22 extends along the entire length of the chamber 14. Here, the flow resistance material 22 is in contact with the side walls 18 of the chamber 14 to prevent gas from bypassing the flow resistance material 22. The backpressure generated by the flow resistance material aids in making the outflow from the first feed slit 8 uniform along its length.

The ALD head includes the monolithic output section 16 including the output face 4 and walls 18 of the first elongate chamber 14. Hence, the output face 4, the chamber 14, and the first elongate feed slit 8 can be monolithic. The monolithic output section 16 can e.g. be 3D-printed from a metal, such as stainless steel.

It has been found that such monolithic output section can easily be cleaned, e.g. in an ultrasonic bath.

In the example of Figures 1 and 2 the flow resistance material 22 is a 3-dimensional, 3D, printed flow resistance material, such as a 3D printed porous material.

This provides the advantage that the flow resistance material 22 can easily be manufactured from a material well suited for cleaning, such as stainless steel, or another metal.

In this example the 3D printed flow resistance material 22 is unitary with the output section 16. Thus the flow resistance material 22 can be manufactured as a single unit with the output section 16. When the input section 20 and output section 16 are unitary, the head 1 can be manufactured as a single unit including the flow resistance material 22. The substrate 2 and/or the head 1 can be mounted so as to be movable, such that the substrate 2 and the head 1 can be moved relative to each other, such asin a direction A perpendicular to the longitudinal direction of the first elongate feed slit 8. Thus, an area on the substrate 2, e.g. having one dimension substantially corresponding to the length of the first feed slit 8, can be covered with a layer of the first material.

Figure 3 shows a schematic cross section of an example of an atomic layer deposition, ALD, head 1. The head 1 of Figure 3 is similar to the head of Figures 1 and 2. In the example of Figure 3, the head 1 includes an elongate return slit 24. The elongate return slit 24 is arranged for, in use, removing gas from the output face 4 and/or the substrate 2. The head 1 here includes an output opening 26 for exhausting gas from the head 1, in communication with the elongate return slit 24. In Figure 3 return flow channels 28 extending from the elongate return slit 24 to the output opening 26 are shown.

The monolithic output section 16 in this example includes the elongate return shit 24. The monolithic input section 20 in this example includes the output opening 26 and ducts of the return flow channel 28.

Figure 4 shows a bottom view of the ALD head 1 of Figure 3. As can be seen in Figure 4, in this example the return slit 24 is positioned such that large portions of the return slit 24 are parallel to the first elongate feed slit 8. Hence, gas can be removed effectively. In this example, the return slit 24 crcumscribes the first elongate feed slit 8. This provides the advantage that all around the first elongate feed slit 8 the gas fed to the substrate 2, but not deposited into a layer, can be removed. Figure 5 shows a schematic cross section of an example of an atomic layer deposition, ALD, head 1. The head 1 of Figure 5 is similar to the head of Figures 3 and 4. In the example of Figure 5, the head 1 includes a second elongate feed slit 30 in the output face 4 for outputting a second gas therethrough towards the substrate 2. The second gas can be a purging gas, such as N2. The ALD head 1 includes a second feed opening 32 for inputting the second gas into the head 1. A second feed flow channel 34 extends from the second feed opening 32 to the second elongate feed slit 30. Hence the head 1 can be used for providing a first gas and a different, second gas to the substrate2, e.g. simultaneously. The second gas can be a purging gas for reducing influence of the head 1 onto neighboring structures, such as neighboring ALD heads. In this example, the head 1 includes in the second feed flow channel 34 a second elongate chamber 35 along the second elongate feed slit 30. The second elongate chamber 35 here includes a flow resistance material 38, e.g. a 3D printed flow resistance material such as a porous material.

In this example, the monolithic output section 16 includes the second elongate feed slit 30. Hence here the first elongate feed slit 8, the second elongate feed slit 30, and the elongate return slit 24 form part of the same monolithic output section 16. In this example, the monolithic input section 20 includes the second feed opening 32 and ducts of the second feed flow channel 34. Hence, here the first feed opening 10, the second feed opening

32, and the output opening 26 form part of the same monolithic input section

20. Figure 6 shows a bottom view of the ALD head 1 of Figure 5. As can be seen in Figure 6, in this example the return slit 24 is positioned such that large portions of the return slit 24 are parallel to the first elongate feed slit 8. Here, the return slit 24 circumscribes the first elongate feed slit 8. In this example the second feed slit 30 is positioned such that large portions of the second elongate feed slit 30 are parallel to the first elongate feed slit 8 and the return slit 24. Here, the second elongate feed sit 30 circumscribes the first elongate feed slit 8 and the return slit 24. This provides the advantage that all around the first elongate feed slit 8 the second gas, such as a purging gas, can be fed to the substrate 2. Hence interaction of the ALD head 1 with adjacent structures, such as adjacent ALD heads, can be reduced which results in more effective operation and/or less contamination.

Figure 7 shows a schematic cross section of an example of an atomic layer deposition, ALD, head 1. The head 1 of Figure 7 is similar to the head of Figures 5 and 6. In the example of Figure 7, the head 1 includes a second elongate return slit 36. The second elongate return slit 36 is arranged for, in use, removing gas from the output face 4 and/or the substrate 2. The head 1 here includes a second output opening 38 for exhausting gas from the head 1, in communication with the second elongate return shit 36. It will be appreciated that the second output opening 38 may be the same as the output opening 26. In Figure 7 second return flow channels 40 extending from the second elongate return slit 36 to the second output opening 38 are shown. The monolithic output section 16 in this example includes the second elongate return slit 36. The monolithic input section 20 in this example includes the second output opening 38 and ducts of the second return flow channel 40.

Figure 8 shows a bottom view of the ALD head 1 of Figure 7. As can be seen in Figure 8, in this example the second return slit 36 is positioned such that large portions of the second return slit 36 are parallel to the second elongate feed slit 30. Hence, gas can be removed effectively. In this example, the second return slit 36 circumscribes the first elongate feed slit 8, the return slit 24 and the second elongate feed slit 30. This provides the advantage that all around the second elongate feed slit 30 the gas fed to the substrate 2 can be removed.

Figure 9 shows two isometric views of an example of an ALD head 1 generally according to Figures 7 and 8. In Figure 9 three cross sections are indicated. Cross section AA is shown in Figure 10. Cross section BB is shown in Figure 11. Cross section CC is shown in Figure 12. In this example, the entire shown ALD head 1 1s monolithic. In this example the entire ALD head is monolithically 3D printed, e.g. from a metal, such as stainless steel.

It is noted that in the example of Figure 9 the head 1 includes two second feed openings 32. These two second feed openings 32 are in mutual connection, allowing gas feed, such as purge gas feed, to be selectively inputted into one of the two openings 32 or both openings simultaneously.

In the example of Figure 10 the first feed opening 10 is circular. The first feed flow channel 12 starts with a circular cross section and mouths into the first elongate chamber 14 with a generally rectangular cross section. It can also be seen that the return flow channel 28 and the second return flow channel 40 connect to a plenum 44. In the cross section AA shown in Figure 10 the first feed flow channel 12 passes through the plenum 44. Walls 46 separate the first feed flow channel 12 from the plenum 44.

In the example of Figure 11 the second feed opening 32 is circular.

The second feed flow channel 34 starts with a circular cross section and bifurcates and mouths into the second elongate chamber 35. In the cross section BB shown in Figure 11 the second feed flow channel 34 passes through the plenum 44. Walls 48 separate the second feed flow channel 34 from the plenum 44.

In the example of Figure 12 the output opening 26 is circular. The return flow channel 26 starts with a circular cross section and mouths into the plenum 44. Figures 13 and 14 show schematic representations of an example of an ALD head unit 100. In this example, the ALD head unit includes a first ALD head 1A and a second ALD head 1B. In the Figures the heads 1A and 1B are drawn at a small distance for clarity. It will be appreciated that in practice the heads 1A and 1B can abut against each other. In Figure 13 the first ALD head 1A is according Figures 7 and 8. In Figure 13 the second ALD head 1B is according Figures 7 and 8. However, it will be appreciated that the first ALD head 1A can be an ALD head as described in view of any of Figures 1-12 and the second ALD head 1B can be an ALD head as described in view of any of Figures 1-12. For clarity only the output sections are shown. In this example, at I a first gas, such as a first process gas is fed into the head 1A and out of the first first elongate feed slit 8A towards the substrate 2. At II a second gas, such as a purge gas is fed into the heads 1A and 1B and out of the second elongate feed slits 30A, 30B towards the substrate 2. At III a third gas, such as a second process gas is fed into the head 1B and out of the second first elongate feed slit 8B towards the substrate

2. At R gas is sucked away from the substrate through the first and second return slits 24A, 24B, 36A, 36B. Hence, the ALD head unit 100 allows supplying of a first and a, optionally different, second process gas to the substrate 2. It will be appreciated that the ALD head unit 100 can include more than two ALD heads as described in view of any of Figures 1-12. Thus, more than two process gasses can be provided to the substrate 2 using the ALD head unit 100. As can be seen in Figure 13, the ALD head unit 100 includes an output face 4 including a first first elongate feed slit 8A for outputting a first process gas therethrough towards a substrate 2 and a second first elongate feed 8B slit for outputting a second process gas therethrough towards a substrate 2. Here the first first feed slit 8A forms a first elongate process feed slit, and the second first feed slit 8B forms a second elongate process feed slit.

Between the first first feed slit 8A and the second first feed slit 8B a first second feed slit 30A and a second second feed slit 30B are placed.

Here the first second feed slit 30A forms a first elongate purge slit, and the second second feed slit 30B forms a second elongate purge slit.

Thus, the ALD head unit 100 is arranged for supplying two, e.g. different, process gases to the substrate simultaneously, here via feed slits 8A and 8B.

In Figure 13 two elongate purge slits 30A, 30B are positioned between two consecutive elongate feed slits 8A, 8B.

By providing at least two elongate purge slits 30A, 30B between two consecutive elongate feed slits 8A, 8B gas separation from one feed slit 8A to the other 8B is greatly improved.

In the example of Figure 13 the first first return slit 24A forms a first return slit, the first second return slit 36A forms a second return slit, the second first return slit 24B forms a third return slit, and the second second return slit 36B forms a fourth return slit.

It will be appreciated that in addition to the ALD heads 1A, 1B, or instead of one thereof, the ALD head unit 100 can include a plasma deposition head as known in the art.

Thus, the ALD head unit 100 can be made suitable both for atomic layer deposition and plasma treatment of the substrate 2. Figure 15 shows schematic representation of an example of an ALD head unit 100. In this example, at I a first gas, such as a first process gas is fed into the head unit 100 and out of the first first elongate feed slit 8A towards the substrate 2. At II a second gas, such as a purge gas is fed into the heads unit 100 and out of the second elongate feed slits 30A, 30B towards the substrate 2. At III a third gas, such as a second process gas is fed into the head unit 100 and out of the second first elongate feed slit 8B towards the substrate 2. At R gas is sucked away from the substrate through the return slits 42A, 42B and 42C. Hence, the ALD head unit 100 allows supplying of a first and a, optionally different, second process gas to the substrate 2. As can be seen in Figure 15, the ALD head unit 100 includes an output face 4 including a first first elongate feed slit 8A for outputting a first process gas therethrough towards a substrate 2 and a second first elongate feed 8B slit for outputting a second process gas therethrough towards a substrate 2. Here the first first feed slit 8A forms a first elongate process feed slit, and the second first feed slit 8B forms a second elongate process feed slit. Between the first first feed slit 8A and the second first feed slit 8B a first second feed slit 30A and a second second feed slit 30B are placed. Here the first second feed slit 30A forms a first elongate purge slit, and the second second feed slit 30B forms a second elongate purge slit. Thus, the ALD head unit 100 is arranged for supplying two, e.g. different, process gases to the substrate simultaneously, here via feed slits 8A and 8B. In Figure 15 two elongate purge slits 30A, 30B are positioned between two consecutive elongate feed slits 8A, 8B. By providing at least two elongate purge slits 30A, 30B between two consecutive elongate feed slits 8A, 8B gas separation from one feed slit 8A to the other 8B is greatly improved.

The ALD heads 1, 1A, 1B, and the ALD head units 100 as described herein can be used in a method 200 for depositing a film of material onto a substrate 2. Figure 16 shows an exemplary flow chart of such method. In a first step 202 the head 1, 1A, 1B or head unit 100 is placed over the substrate

2. In a second step 204A a first process gas is flown out of one of the feed slits 8, 8A, 8B towards the surface of the substrate. Simultaneously with flowing the process gas towards the substrate a purge gas is flown 204B out of the purge slits 30, 30A, 30B. Excess gas can be sucked away 204C from the surface of the substrate 2 through return slits 24, 24A, 24B, 36, 36A, 36B, 42A, 42B, 42C. A layer of material contained in or formable by the first process gas can then be deposited 206 onto the surface of the substrate (or on a previously deposited layer) The ALD head 1, 1A, 1B or ALD head unit 100 can be moved 208 along the surface of the substrate 2, or the substrate 2 can be moved along the head or head unit, or both the substrate and het head/head unit can be moved. When a first layer has been deposited, a next layer can be deposited. This is done in a similar way. Depositing the second layer can involve using a different second process gas, e.g. supplied via a different feed slit, e.g. of a different head 1, 1A, 1B or head unit 100.

Herein, the invention is described with reference to specific examples of embodiments of the invention. It will, however, be evident that various modifications and changes may be made therein, without departing from the essence of the invention. For the purpose of clarity and a concise description features are described herein as part of the same or separate embodiments, however, alternative embodiments having combinations of all or some of the features described in these separate embodiments are also envisaged.

In the examples of Figure 5-14 the ALD head includes a first feed slit 8, 8A, 8B and a second feed slit 30, 30A, 30B. It will be appreciated that it is also possible that the ALD head includes more than two feed slits.

In the examples of Figures 5-14 the second feed slit 30, 30A, 30B circumscribes the first feed slit 8, 8A, 8B. It is also possible that the second feeds slit does not circumscribe the first feed slit. For example, the second feed slit can be a rectangular shit, e.g. parallel with the first feed slit. It is possible that the ALD head includes a rectangular first feed slit and two (or more) rectangular second feed slits, e.g. one on either side of the first feed slit. In the examples of Figures 3-14 the at least one return slit 24, 24A, 24B, 36, 36A, 36B, 42A, 42B, 42C, circumscribes the feed slit. It is also possible that the return slit does not circumscribe the feed slit. For example, the return slit can be a rectangular slit, e.g. parallel with the feed slit. It is possible that the ALD head includes a rectangular feed slit and two (or more) rectangular return slits, e.g. one on either side of the feed slit.

In the examples of Figures 14 and 15 the ALD head unit includes two ALD heads. It will be appreciated that the ALD head unit may also include more than two ALD heads, such as three, four, five, six, eight, ten or twelve ALD heads.

In the examples of Figures 14 and 15 the ALD head unit includes two ALD heads joined together in planar orientation. It will be appreciated that it 1s also possible that the ALD heads may be joined together such that their respective output faces form a curved surface, such as an outer surface of a cylinder. Thereto the respective output face of each ALD head may be curved.

However, other modifications, variations, and alternatives are also possible. The specifications, drawings and examples are, accordingly, to be regarded in an illustrative sense rather than in a restrictive sense.

For the purpose of clarity and a concise description features are described herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features described.

In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word ‘comprising’ does not exclude the presence of other features or steps than those listed in a claim. Furthermore, the words ‘a’ and ‘an’ shall not be construed as limited to ‘only one’, but instead are used to mean ‘at least one’, and do not exclude a plurality. The mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot be used to an advantage.

Claims

Conclusions

An atomic layer deposition (ALD) head unit comprising: an output side comprising: - a first elongate feed slot for outputting a first process gas therethrough to a substrate; - a second elongate feed slot for feeding a second process gas therethrough to a substrate; and - and at least a first and a second elongate purge slot in the output side between the first elongate feed slot and the second elongate feed slot for outputting a purge gas therethrough to a substrate.

The ALD head unit of claim 1, wherein the first elongate coil slot is positioned substantially parallel to the first elongate feed slot, and/or wherein the second elongate coil slot is positioned substantially parallel to the second elongate feed slot.

The ALD head unit of claim 1 or 2, wherein the first elongate coil slot surrounds the first elongate feed slot, and/or wherein the second elongate purge slot surrounds the second elongate feed slot.

The ALD head unit of claim 1, 2 or 3, wherein the output side includes at least one elongate return slot for removing gas from the output side.

The ALD head unit of any one of claims 1 to 4, wherein the output side includes a first elongate return slot positioned between the first elongate feed slot and the first elongate coil slot.

The ALD head unit of claim 5, wherein the first elongate return slot is positioned substantially parallel to the first elongate feed slot.

The ALD head unit of claim 5 or 6, wherein the first elongate return slot surrounds the first elongate feed slot.

The ALD head unit of any one of claims 1 to 7, wherein the output side includes a second elongate return slot positioned between the first elongate purge slot and the second elongate purge slot.

The ALD head unit of claim 8, wherein the second elongate return slot is positioned substantially parallel to the first elongate coil slot.

The ALD head unit of claim 8 or 9, wherein the second elongate return slot surrounds the first elongate return slot.

The ALD head unit of any one of claims 1 to 10, wherein the output side includes a third elongate return slot positioned between the second elongate feed slot and the second elongate coil slot, optionally wherein the third elongate return slot is substantially parallel to the second elongate feed slot and optionally wherein the third elongate return slot surrounds the second elongate feed slot.

The ALD head unit of any one of claims 1 to 11, wherein the output side includes a fourth elongate return slot positioned between the second elongate coil slot and the first elongate coil slot, optionally wherein the fourth elongate return slot is substantially parallel to the second elongate coil slot is positioned, optionally wherein the fourth elongate return slot surrounds the second elongate coil slot.

The ALD head unit according to any one of claims 1 to 12, comprising a monolithic, e.g. 3D printed output section including the output side having the first elongate feed slot and the first elongate coil slot.

The ALD head of claim 13 when dependent on claim 4, wherein the monolithic output section includes the at least one elongate return slot.

The ALD head unit according to any one of claims 1 to 14, comprising an inlet section comprising: - a first feed port for introducing the first process gas into the head unit; - a second feed opening for introducing the purge gas into the head unit; - a first feed flow channel extending from the first feed opening to the first elongate feed slot; and

- a second feed flow channel extending from the second feed opening to the first elongate coil slot.

The ALD head unit of claim 15, wherein the input section is monolithic, such as 3D printed.

The ALD head unit of claim 16 when dependent on claim 4, wherein the monolithic inlet section includes an outlet opening for discharging gas from the head in communication with the at least one elongate return slot and conduits of a reflux channel extending from the at least one elongate return channel. at least one elongate return slot to the output opening.

The ALD head unit of any preceding claim, comprising a first elongate chamber along the first elongate feed slot, the first elongate chamber comprising a flow resistive material.

The ALD head unit of claim 18, wherein the flow resistance material is a, e.g., 3D printed, porous material.

The ALD head unit of any preceding claim comprising a second elongate chamber along the second elongate feed slot, the at least one second elongate chamber comprising a flow resistive material.

The ALD head unit of claim 20, wherein the flow resistance material is a, e.g., 3D printed, porous material.

The ALD head unit of claim 19 or 21, wherein the, e.g., 3D-printed, porous material is a one-piece with the output side.

An atomic layer deposition device comprising one or more ALD head units according to any one of claims 1 to 22.

A method of depositing a thin layer of material on a substrate, comprising moving an ALD head unit according to any one of claims 1 to 23 and a substrate relative to each other while a gas comprising the material is passed through the first elongate feed slot flows to the substrate.

A method of manufacturing a) a photovoltaic element, b) a battery, c) a display, d) flexible electronics, or e) packaging materials comprising depositing a thin layer of material on a substrate according to claim 24.