Methods, inserts, and apparatus for process control and monitoring of thin film deposition - Patents.com

Abstract

A method for determining a penetration depth of a thin film process precursor, comprising providing an insert (100), placing the insert (100) in contact with a substrate (200) to form a plurality of spaces (101) between the insert (100) and the substrate (200), and delivering a precursor into the formed spaces (101) to determine the penetration length of the precursor.

Description

[Technical field]

[0001] The present disclosure relates generally to the field of semiconductor and substrate processing. The disclosure relates specifically, but not exclusively, to process control and monitoring of thin film deposition processes, such as atomic layer deposition (ALD). [Background technology]

[0002] This section describes useful background information that is representative of the prior art and to which no part of the technology described herein is admitted.

[0003] In the field of semiconductor and substrate processing, thin film deposition is used for almost every device. Atomic layer deposition (ALD) is a widely used thin film deposition method based on conformal coating of various 3D shapes. In particular, ALD is an advantageous deposition method for high aspect ratio (HAR) structures.

[0004] However, testing and quantifying conformality as part of process control can be time-consuming and cost-intensive. Conventional test procedures may include, for example, fabricating suitable test samples, depositing thin films on the test samples, sectioning, preparing suitable samples for imaging by scanning electron microscopy (SEM) or transmission electron microscopy (TEM), and analyzing the results of the SEM and TEM imaging. The duration of the above conventional procedures can be several weeks, and the estimated costs of such basic process control procedures can be several thousand euros. Summary of the Invention [Problem to be solved by the invention]

[0005] The accompanying claims define the scope of protection. Any examples of the technical description of the apparatus, product, and / or method in the specification and / or drawings that are not covered by the claims are not defined as embodiments of the present invention, but are defined as background art or examples useful for understanding the present invention.

[0006] It is an aim of certain embodiments of the present invention to enable improved process control and / or monitoring for thin film deposition or to provide an alternative solution to existing techniques. [Means for solving the problem]

[0007] Thus, certain disclosed embodiments provide a unique method for determining the penetration depth of a thin film process precursor. Effect of the Invention

[0008] According to a first exemplary embodiment of the present invention, there is provided a method for determining a penetration depth of a thin film process precursor, comprising the steps of: Providing an insert; placing the insert in contact with a substrate to form a plurality of spaces between the insert and the substrate; and providing the precursor into the formed volume to determine a penetration depth of the precursor; A method for determining the penetration depth of a thin film process precursor is provided, comprising:

[0009] In certain embodiments, the method comprises: providing the precursor into the formed space within a reaction chamber containing the insert and the substrate; This includes:

[0010] In certain embodiments, the method comprises: Delivering the precursor into the formed space using an atomic layer deposition (ALD) sequence. This includes:

[0011] In certain embodiments, the pre-formed space is elongated, enclosed, and / or closed at one end, hi certain embodiments, the pre-formed space is in the form of a tunnel (or cavity).

[0012] In certain embodiments, the space has a curved shape. In certain embodiments, the space has a bent shape. In certain embodiments, the space has a serpentine shape. Thus, for example, instead of being straight, the space may be curved and / or bent and / or serpentine.

[0013] In a particular embodiment, the space is closed at one end thereof, which is located opposite an opening of the space, the opening being connected to an aperture provided in the center of the insert.

[0014] In certain embodiments, the formed space is an elongated space that is open at one end of the space and closed at the other end and is confined along the width of the space by the substrate and / or the insert, the space preferably forming a high aspect ratio structure.

[0015] In certain embodiments, the preformed space is a concentric elongated cavity.

[0016] In certain embodiments, the insert includes a groove configured to form the space between the insert and the base when the insert and the base are in contact with each other.

[0017] In some embodiments, the spaces have different widths or different heights.

[0018] In certain embodiments, the spaces have the same length (depth). In certain embodiments, the flow area of ​​the spaces is rectangular. In certain embodiments, the width of each space is equal, but the height of the spaces varies. In certain embodiments, the height of each individual space is constant, but the width of the spaces varies.

[0019] In certain embodiments, the spaces are spaced apart to prevent the precursor from flowing directly from one space into an adjacent space.

[0020] In certain embodiments, the insert is disc-shaped and / or the shape of the insert is symmetrical about its center.

[0021] In certain embodiments, the insert includes an aperture in the center of the insert and is connected to the space to allow the precursor to be fed into the space through the aperture of the insert. In certain embodiments, the aperture is symmetrically positioned in the center of the insert. In certain embodiments, this allows each inlet hole of the formed space to see a similar flow geometry or similar flow conditions of the precursor. In certain embodiments, the precursor flow into the aperture comes from the top.

[0022] In certain embodiments, the precursor enters the space via diffusion. In certain embodiments, the precursor flows within the space via diffusion.

[0023] In certain embodiments, the insert and the base are oriented horizontally, with the insert resting on top of the base.

[0024] In certain embodiments, the method comprises: The penetration depth is determined by measuring a thin film coating formed on the substrate. This includes:

[0025] In certain embodiments, the method comprises: Obtaining results from measurements of a thin film formed on the substrate, and adjusting the thin film process based on the obtained results. This includes:

[0026] In certain embodiments, the measurements include analyzing precursor penetration depth via ellipsometric characterization or quantitative visual inspection.

[0027] In certain embodiments, results from measurements of the thin film formed on the substrate are provided to an operator. In certain embodiments, an associated apparatus includes at least one processor and at least one memory including a computer program (or computer program code), the at least one memory and the computer program (code) configured with the at least one processor to provide results from measurements of the thin film formed on the substrate to an operator. The associated apparatus may be a data processing device or a computer. The data processing device or computer may be implemented as part of a deposition reactor process control system or separately. The deposition reactor is considered herein as a deposition reactor including a reaction chamber, for example an ALD reactor.

[0028] In certain embodiments, data visualizations are provided to an operator. In certain embodiments, appropriate process description parameters and data visualizations are provided to an operator. In certain embodiments, input data for a computer program and / or associated data analysis are obtained by the methods described above.

[0029] In certain embodiments, a precursor penetration depth measurement is made from the aperture towards the end of the space.

[0030] In certain embodiments, the substrate is a flat substrate, such as a wafer, for example a semiconductor wafer, such as a silicon wafer.

[0031] In certain embodiments, determining the penetration depth by measuring the thin film coating formed on the substrate includes analyzing, by at least one processor, the resulting measurement data (which may be received from a measurement device) and providing a measurement result based on the analysis to an operator.

[0032] According to a second exemplary aspect of the present invention, for determining a penetration depth of a thin film process precursor using the method of the first exemplary aspect or any of its embodiments, there is provided an insert configured to contact a substrate to form a plurality of spaces between the insert and the substrate.

[0033] Thus, in a second exemplary aspect, there is provided an insert configured for use in the method of the first exemplary aspect or any of its embodiments.

[0034] In certain embodiments, the insert includes a groove, the groove configured to form the space when the insert and the base are in contact with one another.

[0035] In certain embodiments, the insert is a separate part. In certain embodiments, the insert does not form part of the base. In certain embodiments, the insert is a part that can be placed in contact with the base. In certain embodiments, the insert is a part that can be placed on top of the base. In certain embodiments, the insert is removable. In certain embodiments, the insert can be in removable contact with the base.

[0036] In certain embodiments, the insert is reusable (i.e., reusable). This means that the same insert can be used multiple times. In certain embodiments, the insert can removably contact the substrate and is reusable. In certain embodiments, the insert can be used for process control and / or monitoring of multiple thin film processes. In certain embodiments, the insert can be used for process control and / or monitoring of all thin film processes in a particular facility.

[0037] According to a third exemplary aspect of the present invention, there is provided an apparatus including at least one processor and at least one memory including a computer program code (or computer program), the at least one memory and the computer program code (or computer program) being configured together with the at least one processor to: placing the insert in contact with the substrate to provide a precursor into a plurality of spaces formed between the insert and the substrate; and determining a penetration depth of the precursor within the formed space; An apparatus is provided, the apparatus being configured to cause the apparatus to perform:

[0038] According to a fourth exemplary aspect of the present invention, there is provided a computer program comprising computer executable program code, the computer executable program code, when executed by a processor, placing the insert in contact with the substrate to provide a precursor into a plurality of spaces formed between the insert and the substrate; and determining a penetration depth of the precursor within the formed space; A computer program for causing the device to execute the is provided.

[0039] According to a fifth exemplary aspect of the present invention, there is provided an apparatus configured to perform thin film deposition and including an insert of the second exemplary aspect or any of its embodiments.

[0040] In certain embodiments, the insert is formed from a polymer and a rigid material, hi certain embodiments, the rigid material comprises a metal or a ceramic material.

[0041] Various non-binding exemplary aspects and embodiments are presented above. The aforementioned embodiments are merely used to illustrate selected aspects or steps that may be utilized in various embodiments. Some embodiments may be presented only with respect to certain exemplary aspects. Needless to say, the corresponding embodiments may also be applied to other exemplary aspects.

[0042] Several exemplary embodiments will now be described with reference to the accompanying drawings. [Brief description of the drawings]

[0043] [Figure 1] FIG. 1 is a flow chart illustrating a method according to an exemplary embodiment. [Figure 2a] FIG. 2a is a schematic diagram showing an insert according to an exemplary embodiment. [Figure 2b] FIG. 2b is a schematic diagram showing an insert according to another exemplary embodiment. [Figure 3a] FIG. 3a is a schematic diagram showing an insert according to yet another exemplary embodiment. [Figure 3b] FIG. 3b is a schematic diagram showing an insert according to yet another exemplary embodiment. [Figure 3c] FIG. 3c is a schematic diagram illustrating an insert according to yet another exemplary embodiment. [Figure 4a] FIG. 4a is a schematic diagram showing a cross-section of the insert. [Figure 4b] FIG. 4b is a schematic diagram showing a cross section at the location indicated in FIG. 4a. [Figure 5a] FIG. 5a is a schematic diagram showing a further location of another cross-section of the insert. [Figure 5b] FIG. 5b is a schematic diagram showing a cross section at the location indicated in FIG. 5a. [Figure 5c] FIG. 5c is a schematic enlarged view of an edge of an insert according to an exemplary embodiment. [Figure 6a] FIG. 6a is a side view of a substrate holder according to an exemplary embodiment. [Figure 6b] FIG. 6b is a close-up view of an edge of the substrate holder according to an exemplary embodiment. [Figure 6c] FIG. 6c is a schematic top view of a substrate holder according to an exemplary embodiment. [Figure 7a] FIG. 7a is a schematic diagram showing an insert, a base, and a base holder according to an exemplary embodiment. [Figure 7b] FIG. 7b is a schematic diagram showing an insert, substrate, and substrate holder, including precursor delivery, according to an exemplary embodiment. [Figure 7c] FIG. 7c is a schematic diagram showing a precursor flow path according to an exemplary embodiment. [Figure 8] FIG. 8 is an enlarged schematic view of the insert, base, and base holder edge. [Figure 9a] FIG. 9a is a schematic diagram illustrating a substrate after precursor deposition according to an exemplary embodiment. [Figure 9b] FIG. 9b shows a visualization of the penetration depth profile in a particular embodiment. [Figure 10] FIG. 10 is a diagram illustrating a process control system in accordance with certain embodiments. [Figure 11] FIG. 11 is a schematic diagram illustrating an apparatus according to an exemplary embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044] In the following description, the atomic layer deposition (ALD) technique is used as an example.

[0045] The fundamentals of ALD growth mechanisms are known to those skilled in the art. ALD is a specialized chemical deposition method based on the sequential introduction of at least two reactive precursor species to at least one substrate. A basic ALD deposition cycle consists of four consecutive steps: Pulse A, Purge A, Pulse B, and Purge B. Pulse A consists of a first precursor vapor, and Pulse B consists of another precursor vapor. During Purge A and Purge B, an inert gas and a vacuum pump are typically used to purge gaseous reaction by-products and residual reactant molecules from the reaction space. A deposition sequence includes at least one deposition cycle. The deposition cycle is repeated until the deposition sequence produces a thin film or coating of the desired thickness. The deposition cycle can also be simpler or more complex. For example, the cycle can include three or more reactant vapor pulses separated by purge steps, or certain purge steps can be omitted. Alternatively, for plasma-assisted ALD, such as PEALD (plasma-enhanced atomic layer deposition), or for photon-assisted ALD, one or more of the deposition steps can be assisted by providing the required additional energy for the surface reaction through feeding plasma or photons, respectively. Alternatively, one of the reactive precursors can be replaced by energy, resulting in a single precursor ALD process. Thus, the sequence of pulses and purges can vary depending on each specific case. The deposition cycles form a timed deposition sequence controlled by a logic unit or microprocessor. Thin films grown by ALD are dense, pinhole-free, and have a uniform thickness.

[0046] For substrate processing steps, at least one substrate is exposed, typically in a reaction vessel (or chamber), to temporally separated precursor pulses to deposit material on the substrate surface by successive self-saturating (or self-limiting) surface reactions. In the context of this application, the term ALD includes all applicable techniques based on ALD, and any equivalent or closely related techniques, such as the following ALD subtypes: MLD (molecular layer deposition), plasma-assisted ALD, such as PEALD (plasma-enhanced atomic layer deposition), and photon-assisted or photon-enhanced atomic layer deposition (also known as flash-enhanced ALD or photo-ALD).

[0047] However, the present invention is not limited to ALD techniques, but may be utilized in a wide variety of substrate processing methods, such as chemical vapor deposition (CVD), and other thin film deposition.

[0048] In the context of ALD techniques, a self-limiting surface reaction means that the surface reaction on the reaction layer at the surface stops and self-saturates when the surface reactive sites are globally depleted.

[0049] 1 shows a flow chart of a method for determining a penetration depth of a thin film process precursor comprising providing an insert (10), placing the insert in contact with a substrate (20) to form a plurality of spaces between the insert and the substrate, and delivering the precursor into the formed spaces (30) to determine the penetration length of the precursor. According to a further embodiment, the method includes determining the penetration depth (40) by measuring a thin film film formed on the substrate. In a particular embodiment, the insert and substrate are contained by a reaction chamber of a deposition reactor, such as an ALD apparatus (or ALD reactor).

[0050] FIG. 2a shows an embodiment of an insert 100. Specifically, FIG. 2a shows a bottom view of the insert 100, which in this embodiment is generally disk-shaped. The insert 100 includes two grooves in its bottom surface. The insert 100 further includes an aperture (through hole) 110 in the center of the insert 100. The grooves have an entrance in a wall surrounding the aperture 110. The grooves are configured to form a space 101 between the insert 100 and a substrate, e.g., a wafer, when the insert 100 is brought into contact with the substrate. In the context of this description, each space 101 has a width, a height, and a depth (length). The width w of the space 101 is the dimension of the space 101 that can be seen from the bottom. This dimension is perpendicular to the radial direction of the insert 100. The length l of the space 101 is the dimension of the space 101 parallel to the direction of the radius of the insert 100, when observing the insert from the bottom. The height h of the space 101 is the remaining dimension of the insert 100 perpendicular to both w and l.

[0051] According to one embodiment, the spaces 101 have different widths w, as shown in Figure 2a. According to this embodiment, the other dimensions of each space 101 (its respective height and its respective length) are equal.

[0052] 2b shows an embodiment of an insert 100 including four grooves configured to form spaces 101 between the insert 100 and a substrate when the insert 100 is brought into contact with the substrate. According to one embodiment, the spaces 101 have different widths w. The other dimensions of each space 101 (its respective height and its respective length) are equal.

[0053] 3a shows an embodiment of an insert 100 that includes eight grooves. The grooves are configured to form spaces 101 between the insert 100 and a substrate when the insert 100 is brought into contact with the substrate. According to this particular embodiment, the spaces 101 have different heights. The other dimensions of each space 101 (its respective width and its respective length) are equal.

[0054] 3b shows an embodiment of an insert 100 that includes twelve grooves. These grooves are configured to form spaces 101 between the insert 100 and a substrate when the insert 100 is brought into contact with the substrate. According to this particular embodiment, the spaces 101 have different heights. The other dimensions of each space 101 (its respective width and its respective length) are equal.

[0055] 3c shows an embodiment of an insert 100 that includes bent grooves. These grooves are configured to form spaces 101 between the insert 100 and a substrate when the insert 100 is brought into contact with the substrate. The bent shape of the grooves allows the spaces 101 to be longer than straight spaces 101. According to this particular embodiment, the spaces 101 have different heights. The other dimensions of each space 101 (respective width and respective length) are equal.

[0056] According to a particular embodiment, when the insert 100 is brought into contact with a substrate (or a substrate surface), spaces 101 are formed between the insert 100 and the substrate 200. In a particular embodiment, the number of spaces 101 is at least two.

[0057] As previously described with reference to Figures 2a, 2b, 3a and 3b, the insert 100 includes an aperture 110 at the center of the insert 100. The aperture 110 is in fluid communication with the space 101, thereby allowing the precursor to be provided to the space 101 through the aperture 110 of the insert 100. According to one embodiment, the precursor enters the space 101 and flows within the space 101 via diffusion. As shown in Figures 2a, 2b, 3a and 3b, the insert 100 is disc-shaped and / or the shape of the insert 100 is symmetrical around its center.

[0058] In certain embodiments, the spaces 101 are elongated, enclosed, and / or closed at one end. In certain embodiments, the spaces 101 are closed at one end of the space 101, the end being located opposite an opening of the space 101 (the opening of the space 101 being located in a wall of the aperture 110). The spaces 101 have different widths or different heights depending on the embodiment. In some embodiments, the spaces 101 have the same length.

[0059] Figure 4a shows a section of the insert 100 of figure 3a. The section is shown by dashed lines. The section is taken through grooves which form spaces 101 with the substrate.

[0060] Figure 4b shows a cross-section of the insert 100 according to the section line shown in figure 4a. In this embodiment, the spaces 101 have different heights h1 and h2. In the particular embodiment shown in figure 4b, the heights h1 and h2 are constant. According to other embodiments, the spaces 101 have a height that decreases in the radial direction.

[0061] The different dimensions of the spaces 101 allow the precursors to travel different distances within each space 101. The wider or taller the space 101, the deeper the precursor will penetrate than in a narrow or shallow space 101. Thin film process variables, such as process pressure, precursor pulse duration, and duration between precursor pulses, have an effect on precursor penetration depth. Thus, by varying the thin film process variables, the precursor will penetrate to different depths within the spaces 101. The height dimensions are exaggerated in FIG. 4b for illustrative purposes.

[0062] In a particular embodiment, the insert 100 is made of a composite of a polymer and a rigid material. The polymer material is preferably relatively soft and heat resistant, such as polymethylmethacrylate (PMMA), polydimethylsiloxane (PDMS), polytetrafluoroethylene (PTFE), or the like. The rigid material is preferably a metal or ceramic plate. In this exemplary embodiment, the grooves of the insert 100 that form the spaces 101 when brought into contact with a substrate are engraved on the polymer material, and a rigid material is added to the insert 100 to maintain the shape of the polymer and facilitate handling. A further technical effect achieved is an improved compensation for shape changes due to thermal expansion through the polymer material.

[0063] Figure 5a shows a further cross-sectional portion of the insert 100 of figure 3a. The cross-section is indicated by a dashed line. The cross-section cuts through the insert 100 in the area between the grooves forming the space 101.

[0064] Figure 5b shows a cross-sectional view of the insert 100 according to the section line shown in Figure 5a. The insert 100 has a diameter d1. The insert 100 has a body with a uniform thickness in the areas that do not form spaces 101. The spaces 101 are thus separated from each other, preventing the precursor from flowing from one space 101 to an adjacent space 101.

[0065] Fig. 5c shows a schematic close-up of the edge of the insert 100. In a particular embodiment, the edge of the insert 100 has a horizontally extending protrusion 120. The protrusion 120 allows the insert to be moved, lifted and submerged. In a particular embodiment, the protrusion 120 is positioned in the upper corner of the edge of the insert 100. The diameter d1 represents the outer diameter of the insert 100 between the edges in the region of the edge without the protrusion 120.

[0066] According to an optional embodiment, the insert 100 has a vertical protrusion (notch) 130 that protrudes from the outer edge of the bottom of the insert 100. The protrusion 130 allows the insert 100 and base 200 to be centered. The protrusion 130 is a guide for the alignment of the insert 100 and base 200.

[0067] 6a shows a cross-sectional view of the substrate holder 300 according to a particular embodiment. In a particular embodiment, the top surface of the substrate holder 300 has the shape of a round plate. In a particular embodiment, the round plate receives the substrate and the insert is positioned onto the substrate prior to precursor delivery. The substrate holder 300 has an inner diameter d2 and an outer diameter d3.

[0068] 6b shows a schematic close-up of the edge of the substrate holder 300. The edge of the substrate holder 300 has protrusions 310. The protrusions 310 allow the insert to be moved, lifted and lowered. The protrusions 310 allow the substrate to be placed on top of the substrate holder 300. The protrusions 310 prevent the substrate from sliding or moving on top of the substrate holder 300.

[0069] 6c shows the substrate holder 300 from above. The protrusions 310 are visible from above and extend around the circular edge of the substrate holder 300. The inner diameter d2 of the substrate holder 300 is smaller than the outer diameter d3 of the substrate holder 300. In certain embodiments, the substrate holder 300 has a recess 320, or at least two recesses 320 as shown in FIG. 6c. The recesses 320 allow a loading tool or a tool operator to grip the substrate.

[0070] Fig. 7a shows the insert 100, the base 200 and the base holder 300 in a side view. The base 200 is placed on top of the base holder 300. The diameter d1 of the insert 100 is smaller than the inner diameter d2 of the base holder 300, but slightly larger than the diameter of the base 200. The insert 100 is placed on top of the base 200. The contact between the base 200 and the insert 100 forms a number of spaces 101 between the insert 100 and the base 200. According to one embodiment, the insert 100 is on top of (or is placed on top of) the base 200 when the insert 100 and the base 200 are placed in a horizontal orientation. In certain embodiments, the bottom side of the insert 100 is in contact with the top side of the base 200 except where the apertures 110 and spaces 101 are located (and at the location of any protrusions (notches) 130 that simply surround the base 200).

[0071] 7 shows the insert 100, substrate 200, and substrate holder 300, including the precursor delivery, which is through an aperture 110 in the center of the insert 100.

[0072] FIG. 7c shows the flow path of the precursor. As mentioned above, the precursor is delivered through the aperture 110 in the center of the insert 100. The aperture 110 is in fluid communication with the preformed space (or high aspect ratio structure) 101, which allows the precursor to be delivered through the aperture 110 of the insert 100 into the space 101. The precursor first flows downstream through the aperture 110, and as it approaches the surface of the substrate 200, the precursor flow turns and flows horizontally along the surface of the substrate 200 into the space 101. According to one embodiment, the precursor enters the space 101 via diffusion. The spaces 101 have different widths or different heights. In a particular embodiment, the spaces 101 have the same length. Thus, the precursor flow penetrates various depths of the space 101. While penetrating the space 101, the precursor forms a thin film on the surface of the substrate 200. After the precursor flow reaches its maximum penetration depth, the remaining precursor and reaction products (if any) flow back through aperture 110. The precursor then flows along the surface and over the edge of insert 100, after which the precursor exits the reaction space and is removed via an exhaust line (not shown).

[0073] FIG. 8 shows an enlarged side view of the insert 100, the substrate 200, and the edge of the substrate holder 300. The protrusion 130 allows the insert 100 and the substrate 200 to be centered relative to one another. The protrusion 130 is a guide in the alignment of the insert 100 and the substrate 200. In one embodiment, the method includes obtaining results from a measurement of a thin film formed on a substrate and adjusting the thin film process based on the obtained results. In one embodiment, the measurement includes analyzing the precursor penetration depth via quantitative visual inspection, or ellipsometric characterization, or other suitable characterization techniques. The ellipsometric characterization or other suitable characterization techniques are performed via a suitable measurement apparatus (or device). In a particular embodiment, the measurement of the precursor penetration depth is performed from the aperture 110 toward the end of the space 110.

[0074] Monitoring and program control of thin film deposition is accomplished by quantifying the penetration depth of the thin film volume. Figure 9a shows the substrate 200 after precursor deposition. According to one embodiment, the naked eye can determine how the thin film deposition forms a thin film in the space 101 (and onto the substrate 200 below) through quantitative visual inspection. The thin film deposition forms an image 210 on the substrate 200. In the image, it can be visually observed how the penetration depth changes between the spaces 101 as the width or height is changed.

[0075] Quantitative visual inspection may include comparing the formed thin film image 210 to a glass disk having a scale written on it. In this case, the visual inspection involves comparing the formed image 210 to the scale on the glass disk. An operator can note the readings indicated by the scale on the glass disk and compare these readings to known values ​​for optimal operating conditions. By comparing the scale readings, an operator can note if the process conditions being monitored are not optimal.

[0076] A model substrate may be provided in the processing facility with an ideal image representing ideal process conditions for monitoring the process. The model substrate may be obtained by coating a substrate according to the disclosed method at the optimum operating conditions found for generating the ideal image. For process control and / or monitoring, an operator may use existing process conditions to subsequently implement the disclosed method to form a "monitor substrate" (or a substrate with an image being monitored). The operator can then visually compare the monitor substrate with the model substrate. The operator can note if the process conditions during monitoring are not optimal. The operator can then improve the process quality by adjusting the process variables accordingly.

[0077] The ellipsometric characterization includes the characterization of the penetration depth of the precursor. In one embodiment, the ellipsometric characterization may further include the characterization of the thickness profile of the thin film. A computer program is used to assist the operator in data analysis and / or visualization of the ellipsometric characterization for greater efficiency and repeatability. Figure 9b shows the visualization of the penetration depth analysis in a particular embodiment. The visualization labels several tunnels with different tunnel heights and shows the penetration depth in the tunnels as well as the thickness of the thin film coating formed on the substrate.

[0078] FIG. 10 shows a block diagram of a computerized process control system for a deposition apparatus or reactor according to certain exemplary embodiments. The control system 750 includes at least one processor 751 for controlling the operation of the apparatus and at least one memory 752 containing a computer program or software 753. The software 753 includes instructions or program code to be executed by the at least one processor 751 to control the apparatus. The software 753 may typically include an operating system and a variety of different applications. The control system 750 may be configured as a computerized system. A computerized system uses one or more computers.

[0079] At least one memory 751 may form part of the apparatus or may comprise an attachable module. The control system 750 further comprises at least one communication unit 754. The communication unit 754 provides an interface for internal communication of the measurement apparatus. In a particular embodiment, the control unit 750 uses the communication unit 754 to send instructions or commands and to receive data from different parts of the apparatus, such as measurement and control devices, valves, and other regulating devices (not shown).

[0080] The control system 750 may further include a user interface 756 to interact with an operator and receive input, such as, for example, process parameters, from the operator. In certain embodiments, the user interface 756 is coupled to the at least one processor 751.

[0081] With respect to the operation of the apparatus, the control system 750 controls the delivery of precursor vapors into the spaces formed between the insert 100 and the substrate 200, for example, to determine the penetration depth.

[0082] In certain embodiments, the control system 750 includes a measurement device 757 that enables measurements, such as ellipsometry characterization measurements for further analysis. According to certain embodiments, the measurement device 757 is configured, for example by programming, to perform a measurement sequence on the substrate 200. According to certain embodiments, the measurement device 757 is programmed to collect results (measurement data) of the measurements performed during the measurement sequence.

[0083] The program modules may be executed as part of the control system 750 or separate from the control system 750. The program modules analyze the obtained measurement data. In certain embodiments, the program modules (or program code) are executed in the software 753. According to certain embodiments, the at least one processor 751 performs data analysis on the obtained measurement data. In certain embodiments, the measurement data received from or obtained from the measurement device 757 is analyzed by the at least one processor 751 to determine the penetration depth, and measurements and / or visualizations based on the analysis are provided to the operator. The measurements / visualizations may be presented on the user interface 156 or a separate display device.

[0084] FIG. 11 illustrates an apparatus 800, such as an ALD reactor or another deposition apparatus, configured to perform the disclosed methods according to certain embodiments. The apparatus 800 includes a reaction chamber 801 that encloses a reaction space 810. The reaction space 810 may be heated. The reaction chamber 801 contains a substrate 200 and an insert 100 in contact with the substrate 200. In certain embodiments, the substrate 200 and the insert 100 are supported by a substrate holder 300. Precursors (A, B) (or precursor vapors) are fed into the reaction chamber 801 through an inlet 802. The precursors (A, B) are fed into the inlet 802 from respective precursor containers 805, 806 through respective pipelines 803, 804. For ALD processing, the precursors (A, B) are fed alternately. After the apparatus 800 performs the thin film deposition process, the remaining precursors (A, B) exit the reaction chamber 801 via exhaust line 807. In one embodiment, the two precursors (A, B) are fed into the reaction chamber 801 from the top and exhausted from the bottom.

[0085] Without limiting the scope and interpretation of the claims, certain technical effects of one or more of the exemplary embodiments disclosed herein are listed below. A technical effect of the present invention is faster and cheaper control and monitoring of thin film deposition processes. A further technical effect is reduced downtime in production due to faster process control and monitoring. A further technical effect is more agile adjustment of the thin film deposition process. A further technical effect is enabling quantitative visual inspection in process control and monitoring. A further technical effect is that the same insert can be used multiple times, i.e. the insert can be reused, which minimizes the amount of waste that would otherwise result from a single use process control and / or monitoring means.

[0086] Various embodiments have been presented. It will be appreciated that the terms "comprise", "include" and "contain" are used herein as open-ended expressions, with no exclusivity intended.

[0087] The above description provides a complete and informative description of the best mode currently contemplated by the inventor for carrying out the invention, as non-limiting examples of specific implementations and embodiments. However, as will be apparent to those skilled in the art, the invention is not limited to the details of the embodiments presented above, and may be carried out in other embodiments using equivalent means or in various combinations of the embodiments without departing from the characteristics of the invention.

[0088] Moreover, some of the features of the exemplary embodiments disclosed hereinabove may be used to advantage without the corresponding use of other means. As such, the foregoing description should be considered as merely illustrative of the principles of the invention, and not in limitation thereof. The scope of the invention is therefore limited only by the appended claims.

Claims

1. 1. A method for determining penetration depth of a thin film process precursor, comprising: Providing an insert; placing the insert in contact with a substrate to form a plurality of spaces between the insert and the substrate; and providing the precursor into the formed volume to determine a penetration depth of the precursor; 16. A method for determining penetration depth of a thin film process precursor, comprising:

2. providing the precursor into the formed space within a reaction chamber containing the insert and the substrate; The method of claim 1 , comprising:

3. The method of claim 1 or 2, comprising providing the precursor into the formed space by using an atomic layer deposition (ALD) sequence.

4. 4. The method of claim 1, wherein the formed space is an elongated space, open at one end of the space and closed at the other end, and confined along a width of the space by the substrate and / or the insert, the space preferably forming a high aspect ratio structure.

5. 5. The method of claim 1, wherein the insert includes a groove, the groove configured to form the space between the insert and the base when the insert and the base are in contact with each other.

6. The method according to any one of claims 1 to 5, wherein the spaces have different widths or different heights.

7. 7. The method of claim 1, wherein the spaces are spaced apart to prevent the precursor from flowing directly from one space into an adjacent space.

8. 8. The method of claim 1, wherein the insert is disc-shaped and / or the shape of the insert is symmetrical about its centre.

9. 9. The method of claim 1, wherein the insert includes an aperture at the center of the insert and is connected to the space to allow precursor delivery into the space through the aperture of the insert.

10. 10. The method of claim 1, wherein the precursor flows within the space via diffusion.

11. 11. The method of claim 1, wherein the insert and the substrate are oriented horizontally, the insert being located on top of the substrate.

12. The penetration depth is determined by measuring a thin film coating formed on the substrate. The method of any one of claims 1 to 11, comprising:

13. Obtaining results from measurements of a thin film formed on the substrate, and adjusting the thin film process based on the obtained results. The method of claim 12, comprising:

14. The determination is analyzing, by at least one processor, the obtained measurement data; and The measurement results based on the analysis are provided to the operator. The method of claim 12, comprising:

15. 15. An insert configured to contact a substrate to form a plurality of spaces between the insert and the substrate for determining a penetration depth of a thin film process precursor using the method of any one of claims 1 to 14.

16. 16. The insert of claim 15, comprising a groove configured to form the space when the insert and the base are in contact with one another.

17. 17. An insert according to claim 15 or 16, wherein the insert is removable.

18. 19. An insert according to any one of claims 15 to 18, wherein the insert is reusable.

19. 1. An apparatus including at least one processor and at least one memory including computer program code, the at least one memory and the computer program code operating in conjunction with the at least one processor to: placing the insert in contact with the substrate to provide a precursor into a plurality of spaces formed between the insert and the substrate; and determining a penetration depth of the precursor within the formed space; The apparatus is configured to cause the apparatus to perform the steps.

20. A computer program comprising computer executable program code, said computer executable program code, when executed by a processor, placing the insert in contact with the substrate to provide a precursor into a plurality of spaces formed between the insert and the substrate; and determining a penetration depth of the precursor within the formed space; A computer program that causes the device to execute the above steps.

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