Measurement system for determining a thickness of a layer to be deposited on a substrate plane of a substrate, deposition apparatus, and method of determining a thickness of a layer

Abstract

A measurement system (100) for determining a thickness of a layer to be deposited on a substrate surface (11) of a substrate (10) is described. The measurement system (100) includes at least one thickness gauge (110) coupled to a carrier (120), wherein a measurement surface (111) of the at least one thickness gauge (110) is positioned in a substrate plane (12) of the substrate surface (11) of the substrate (10).

Description

MEASUREMENT SYSTEM FOR DETERMINING A THICKNESS OF A LAYER TO BE DEPOSITED ON A SUBSTRATE PLANE OF A SUBSTRATE, DEPOSITION APPARATUS, AND METHOD OF DETERMINING A THICKNESS OF A LAYERTECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to deposition of materials, e.g. for display manufacturing, on substrates. In particular, embodiments of the present disclosure relate to measurement systems for determining a thickness of a layer to be deposited on a substrate surface of a substrate. Further embodiments of the present disclosure relate to deposition apparatuses for depositing material on a substrate. Yet further embodiments relate to methods of determining a thickness of a layer to be deposited on a substrate surface of a substrate.BACKGROUND

[0002] For devices comprising thin film layers, such as OLED devices, meticulous control of film thickness is imperative to meet stringent performance specifications and uphold overall quality standards. Particularly in the realm of OLED devices, a thickness repeatability of ±2% between substrates is the established norm, with an escalating demand for even tighter tolerances to achieve superior device performance and elevate overall quality.

[0003] In pursuit of highly accurate thickness control, the ongoing development involves the implementation of in-situ thickness measurement techniques. However, it is essential to acknowledge that existing solutions, such as spectroscopic reflectometry and spectroscopic ellipsometry, exhibit certain limitations.

[0004] Spectroscopic reflectometry encounters limitations in providing the required sensitivity when dealing with ultra-thin layers, specifically those with thicknesses of 20nm or less. This method faces difficulties in accurately discerning the thickness of each individual layer within a multi-layered structure, demanding dedicated measurement spots for precise characterization.

[0005] Spectroscopic ellipsometry offers the capability to measure extremely thin layers, even as thin as 10nm or less, with the necessary sensitivity. However, it comes with the trade-off of requiring a larger system footprint and a more extended measurement duration. While it provides the potential to measure the thickness of individual layers in a multi-layered structure, the process necessitates a larger system size and incurs a time overhead.

[0006] Accordingly, there is a demand for improved measurement systems, improved deposition apparatuses, and improved methods of determining layer thickness which at least partially overcome one or more of the disadvantages of the state of the art.SUMMARY

[0007] In light of the above, a measurement system for determining a thickness of a layer to be deposited on a substrate surface of a substrate, a deposition apparatus for depositing material on a substrate, and a method of determining a thickness of a layer to be deposited on a substrate surface of a substrate according to the independent claims are provided. Further aspects, benefits, and features of the present disclosure are apparent from the claims, the description, and the accompanying drawings.

[0008] According to an aspect of the present disclosure, a measurement system for determining a thickness of a layer to be deposited on a substrate surface of a substrate is provided. The measurement system includes at leastone thickness gauge coupled to a carrier. A measurement surface of the at least one thickness gauge is positioned in the substrate plane of the substrate surface of a substrate.

[0009] According to another aspect of the present disclosure, a deposition apparatus for depositing material on a substrate is provided. The deposition apparatus, includes a vacuum deposition chamber, a deposition source provided inside the vacuum deposition chamber, and a measurement system according to any embodiments described herein.

[0010] According to a further aspect of the present disclosure, a method of determining a thickness of a layer to be deposited on a substrate surface of a substrate is provided. The method includes moving a carrier past at least one deposition source. The carrier includes at least one thickness gauge. A measurement surface of the at least one thickness gauge is positioned in a substrate plane of the substrate surface of the substrate. Additionally, the method includes depositing material on the measurement surface by the at least one deposition source. Further, the method includes determining a thickness of the layer to be deposited on the substrate surface by evaluating the amount of material deposited on the measurement surface.

[0011] Embodiments are also directed at apparatuses for carrying out the disclosed methods and include apparatus parts for performing each described method aspect. These method aspects may be performed by way of hardware components, a computer programmed by appropriate software, by any combination of the two or in any other manner. Furthermore, embodiments according to the disclosure are also directed at methods for operating the described apparatus. The methods for operating the described apparatus include method aspects for carrying out every function of the apparatus.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments. The accompanying drawings relate to embodiments of the disclosure and are described in the following:FIG. 1 shows a schematic front view of a measurement system according to embodiments of the present disclosure;FIG. 2 shows a sectional view along line A-A indicated in FIG. 1 ;FIG. 3 shows a schematic front view of a measurement system having a plurality of thickness gauges provided at different vertical positions according to embodiments of the present disclosure;FIG. 4 shows a sectional view along line B-B indicated in FIG. 3;FIG. 5 shows a schematic front view of a measurement system having a plurality of thickness gauges provided at different vertical and horizontal positions according to embodiments of the present disclosure;FIG. 6 shows a schematic front view of a measurement system having a shutter according to further embodiments of the present disclosure;FIG. 7 shows a sectional view along line C-C indicated in FIG. 6;FIG. 8 shows a schematic front view of a measurement system having a plurality of groups of thickness gauge;FIG. 9 shows a sectional view along line D-D indicated in FIG. 8;FIG. 10 shows a schematic view of a deposition apparatus according to embodiments of the present disclosure; andFIG. 11 shows a block diagram for illustrating a method of determining a thickness of a layer to be deposited on a substrate surface of a substrate according to embodiments of the present disclosure.DETAILED DESCRIPTION OF EMBODIMENTS

[0013] Reference will now be made in detail to the various embodiments, one or more examples of which are illustrated in each figure. Each example is provided by way of explanation and is not meant as a limitation. For example, features illustrated or described as part of one embodiment can be used on or in conjunction with any other embodiment to yield yet a further embodiment. It is intended that the present disclosure includes such modifications and variations.

[0014] Within the following description of the drawings, the same reference numbers refer to the same or to similar components. Generally, only the differences with respect to the individual embodiments are described. Unless specified otherwise, the description of a part or aspect in one embodiment can apply to a corresponding part or aspect in another embodiment as well.

[0015] With exemplary reference to FIGS. 1 and 2, a measurement system 100 for determining a thickness of a layer to be deposited on a substrate surface 11 of a substrate 10 according to embodiments of the present disclosure is described.

[0016] In the present disclosure, a “measurement system for determining a thickness of a layer to be deposited on a substrate surface of a substrate” can be understood as a system or setup configured to measure and determine a thickness of a layer that will later be deposited on a substrate surface. Accordingly, the measurement system may also be referred to as a calibration system. In particular, the measurement system can be used as a calibrationsystem for calibrating a deposition source with respect to a thickness of a layer to be deposited on a substrate surface. In other words, the measurement system can serve as a calibration tool for calibrating a deposition source to achieve a target thickness of a layer on a substrate surface.

[0017] FIG. 1 sows a schematic front view of the measurement system and FIG. 2 shows a sectional view along line A-A indicated in FIG. 1 . According to embodiments, which can be combined with other embodiments described herein, the measurement system 100 includes at least one thickness gauge 110 coupled to a carrier 120. As exemplarily shown in FIG. 2, a measurement surface 111 of the at least one thickness gauge 110 is positioned in a substrate plane 12 of the substrate surface 11 of the substrate 10.

[0018] Accordingly, compared to the state of the art, an improved measurement system is provided. In particular, the measurement system according to embodiments described herein is beneficially configured to measure the thickness of a layer to be deposited in situ within a vacuum deposition apparatus. Compared to the state of the art, the measurement system offers significant advantages that enhance both efficiency and reliability. Notably, the measurement system simplifies live tooling, making it easier to maintain consistent repeatability specifications. "Simplifying live tooling" refers to making the process of adjusting and controlling tools during an ongoing layer deposition easier and more efficient. In the context of the measurement system, live tooling typically involves real-time adjustments to the equipment or tools used to deposit materials on a substrate. Accordingly, deposition parameters can be quickly and accurately modified during operation in-situ without interrupting the workflow. This simplification helps maintain consistency and repeatability in the measurements and material deposition, reducing errors and improving the overall efficiency of the process.

[0019] Additionally, the measurement system is beneficially configured to provide instant feedback without delays, such as those encountered with surface ellipsometry (SE) measurements. The immediate response of themeasurement system not only enhances yield but also reduces the time required for the measurement. By eliminating the frequent need of a SE measurement for absolute thickness measurements, the measurement system further boosts overall productivity.

[0020] Before various further embodiments of the present disclosure are described in more detail, some aspects with respect to some terms used herein are explained.

[0021] In the present disclosure, a “thickness gauge” can be understood as an instrument or device configured to measure the thickness of a layer that will be deposited on a substrate surface. Typically, the thickness gauge is attached to a carrier as described herein. In particular, the thickness gauge is positioned so that the measurement surface of the thickness gauge aligns with the substrate plane of the substrate surface onto which the layer is to be deposited later. The alignment ensures precise determination of the intended thickness of the layer which is to be deposited on the substrate surface. In other words, typically the measurement system operates without the actual substrate being present, allowing accurate pre-deposition measurements to ensure the correct thickness of the layer to be applied later.

[0022] According to embodiments, which can be combined with other embodiments described herein, the at least one thickness gauge 110 includes a piezoelectric resonator. The piezoelectric resonator may be a crystal oscillator, such as a quartz crystal oscillator. The piezoelectric resonator may be a polycrystalline and / or ceramic oscillator. In particular, the piezoelectric resonator may be a resonator for use with a microbalance, particularly a quartz crystal microbalance (QCM). The piezoelectric resonator may include at least one essentially flat surface, such as two essentially flat surfaces, such as two opposed essentially flat surfaces. In particular, one essentially flat surface of the piezoelectric resonator provides the measurement surface of the at least one thickness gauge as described herein. The piezoelectric resonator may have one or more electrodes formed on the at least one essentially flat surface,such as two electrodes formed on the two essentially flat surfaces, particularly for providing a voltage, such as an alternating voltage, to a portion of the piezoelectric resonator, particularly to cause the piezoelectric resonator to oscillate. The piezoelectric resonator may form a resonator of a microbalance, particularly a quartz crystal microbalance, when electrically connected to a driver. The driver may be a driver of a microbalance, particularly a quartz crystal microbalance. The piezoelectric resonator may comprise a quartz crystal, particularly an AT-cut quartz crystal or an RC-cut quartz crystal. The quartz crystal may be essentially disc-shaped and have, on each face of the disc, an electrode formed thereon. The piezoelectric resonator may be a QCM chip.

[0023] Typically, the piezoelectric resonator may have a resonant frequency. The resonant frequency of the piezoelectric resonator may be affected according to a mass of a material deposited onto the measurement surface (i.e. one of the at least one essentially flat surface of the piezoelectric resonator). Particularly, depositing a material onto the measurement surface of the piezoelectric resonator may result in an increase in mass on the surface and a decrease in the resonant frequency of the piezoelectric resonator. The resonant frequency, particularly a change and / or decrease of the resonant frequency, may be indicative of a layer thickness of a material deposited onto the measurement surface.

[0024] In the present disclosure, a “carrier” can be understood as a mechanical structure configured to transport at least one thickness gauge past one or more deposition sources provided inside a vacuum deposition chamber of a deposition apparatus. Accordingly, a carrier is typically configured to travel within the deposition apparatus.

[0025] With exemplary reference to FIGS. 3 and 4, according to embodiments, which can be combined with other embodiments described herein, the at least one thickness gauge comprises a plurality of thickness gauges 110 provided at different vertical positions. In particular, FIG. 3 showsan example in which a first thickness gauge 110A having a first measurement surface 111A, a second thickness gauge 110B having a second measurement surface 111 B, and a third thickness gauge 110C having a third measurement surface 111 C are provided at different vertical positions. The vertical direction is indicted by arrow y and the horizontal direction is indicated by arrow x in the figures.

[0026] Additionally, or alternatively, a plurality of thickness gauges 110 can be provided at different horizontal positions, as exemplarily shown in FIG. 5. In particular, FIG. 5 shows an exemplary configuration in which a first thickness gauge 110A, a second thickness gauge 110B and a third thickness gauge 110C are arranged along a first virtual vertical line 113. A fourth first thickness gauge 110D, a fifth thickness gauge 110E, and a sixth thickness gauge 11 OF can be arranged along a second virtual vertical line 114 space apart from the first virtual vertical line 113 by a horizontal distance D. Typically, the second virtual vertical line 114 is parallel to the first virtual vertical line 113.

[0027] A configuration with a plurality of thickness gauges provided at different vertical positions and / or different horizontal positions in the substrate plane has the advantage that information about deposition uniform ity / layer thickness uniformity in the substrate plane can be obtained.

[0028] According to embodiments, which can be combined with other embodiments described herein, the measurement system 100 further includes a shutter 130 configured to cover the measurement surface 111 of the at least one thickness gauge 110, as exemplarily shown in FIG. 6. Typically, the shutter 130 is a movable shutter. For instance, the shutter 130 can be a plate, particularly a disk, having at least one measurement opening 131. According to an example, the shutter 130 is rotatable around a shutter rotation axis 132 being perpendicular to the measurement surface 111. FIG. 6 shows an example in which one shutter 130 is provided for a plurality of thickness gauges 110. It is to be understood that depending on the rotational angle of the shutter 130 about the shutter rotation axis 132, the measurement opening131 can be positioned such that the measurement surfaces of the individual thickness gauges 110 is accessible, i.e. can be exposed to evaporated material provided from a deposition source.

[0029] With exemplary reference to FIG. 7, according to embodiments, which can be combined with other embodiments described herein, the at least one thickness gauge 110 includes at least one group 112 of thickness gauges coupled to a common movable support 140. The common movable support 140 can be rotatable around a rotation axis 141 being perpendicular to the measurement surface 111. The common movable support 140 can be coupled to a second actuator 162 to rotate the common movable support 140 about the rotation axis 141 . Accordingly, a configuration with a common movable support 140 as described herein may also be referred to as a “revolver configuration”.

[0030] According to embodiments, which can be combined with other embodiments described herein, the at least one group 112 of thickness gauges comprises a plurality of groups of thickness gauges, wherein individual groups of thickness gauges are coupled to individual common movable supports. Typically, the individual common movable supports are rotatable around different rotation axes being perpendicular to the measurement surface 111.

[0031] FIG. 8 shows an exemplary measurement system 100 having three groups of thickness gauges, namely a first group 112A of thickness gauges, a second group 112B of thickness gauges, and a third group 112C of thickness gauges. Typically the individual groups of thickness gauges are provided at different vertical and / or different horizontal positions. As exemplary shown in FIG. 9, the first group 112A of thickness gauges can be coupled to a first common movable support 140A. The first common movable support 140A can be rotatable around a first rotation axis 141 A being perpendicular to the measurement surfaces of the thickness gauges of the first group 112A. The second common movable support 1406 can be rotatable around a second rotation axis 141 B being perpendicular to the measurement surfaces of the thickness gauges of the second group 112B. The third common movablesupport 140C can be rotatable around a third rotation axis 141 C being perpendicular to the measurement surfaces of the thickness gauges of the third group 112C. It is to be understood that the first common movable support 140A, the second first common movable support 1406 and the third first common movable support 140C can be configured as the common movable support 140 as exemplary described with reference to FIGS. 6 and 7.

[0032] Further, as exemplary shown in FIG. 8, according to embodiments, which can be combined with other embodiments described herein a first shutter 130A for the first group 112A of thickness gauges can be provided. Additionally or alternatively, a second shutter 130B for the second group 112B of thickness gauges can be provided. Additionally or alternatively, a third shutter 130C for the third group 112C of thickness gauges can be provided. It is to be understood that the first shutter 130A, the second shutter 130B and the third shutter 130C can be configured as the shutter 130 as exemplary described with reference to FIGS. 6 and 7. The first shutter 130A has a first shutter rotation axis 132A. The second shutter 130B has a second shutter rotation axis 132B. The third shutter 130C has a third shutter rotation axis 132C.

[0033] With exemplary reference to FIG. 7, according to embodiments, which can be combined with other embodiments described herein, the carrier 120 includes a power supply 150, particularly a battery, connected to the at least one thickness gauge 110. Further, the power supply 150 can be connected to a first actuator 161 to move, particularly to rotate, a shutter 130 according to embodiments described herein. Additionally or alternatively, the power supply 150 can be connected to a second actuator 162 to move, particularly to rotate, a common movable support 140 according to embodiments described herein.

[0034] According to embodiments, which can be combined with other embodiments described herein, the measurement system 100 further includes an evaluation unit 170. The evaluation unit 170 can be coupled to the carrier120, as exemplary shown in FIG. 7. Alternatively, the evaluation unit 170 may be decoupled from the carrier 120. For instance, the evaluation unit 170 can be an external evaluation unit 171 , as exemplarily indicated in FIGS. 7 and 10. The external evaluation unit 171 can be provided at a specific position within a deposition apparatus 200 in which the carrier 120 is employed. The evaluation unit 170 coupled to the carrier or the external evaluation unit 171 typically includes a frequency analyzer, particularly for determining a frequency, particularly a resonant frequency of an oscillator including, a piezoelectric resonator as described herein.

[0035] According to embodiments, which can be combined with other embodiments described herein, the measurement system 100 includes a driver 155, as exemplarily shown in FIG. 7. The driver 155 may be connected to an evaluation unit 170 coupled to the carrier. Alternatively, the driver may be connectable to an external evaluation unit 171. A connection between the driver 155 and the evaluation unit 170 coupled to the carrier or the external evaluation unit 171 can be a wired or wireless connection. The driver 155 is configured for providing a voltage, particularly an alternating voltage, to the piezoelectric resonator, particularly the electrodes of the piezoelectric resonator. The driver may be configured for tuning the alternating voltage to the resonant frequency of the piezoelectric resonator. Alternatively, the driver may be configured for driving the piezoelectric resonator at a predetermined frequency, and perform an impedance analysis for a frequency range.

[0036] With exemplary reference to FIG. 7, according to embodiments, which can be combined with other embodiments described herein, the measurement system further includes at least one heater 180 to heat the at least one thickness gauge 110, particularly the measurement surface 111 of the at least one thickness gauge 110. The heater 180 can, for example, be provided at a backside of the shutter facing the measurement surface 111. According to an alternative example (not explicitly shown), the heater 180 can be integrated in the at least one thickness gauge 110. In particular, theheater 180 is configured to re-evaporate material deposited on the measurement surface 111. Accordingly, the heater 180 can be used for cleaning the measurement surface 111.

[0037] With exemplary reference to FIG. 10, a deposition apparatus 200 for depositing material on a substrate 10 according to embodiments of the present disclosure is described. According to embodiments, which can be combined with other embodiments described herein, the deposition apparatus 200 includes a vacuum deposition chamber 210, a deposition source 220 provided inside the vacuum deposition chamber 210, and a measurement system 100 according to any embodiments described herein. The measurement system 100 includes at least one thickness gauge 110 coupled to a carrier 120. The measurement surface 111 of the at least one thickness gauge 110 is positioned in a substrate plane 12 of a substrate surface 11 of a substrate 10 onto which a layer is to be deposited. As shown in FIG. 10, during operation, the measurement surface 111 is directed towards the deposition source 220. Further, as shown in FIG. 10, during operation a front side 12F of the carrier 120 is directed towards the deposition source 220. A back side 12B of the carrier 120 is opposite to the front side 12F of the carrier 120.

[0038] The deposition apparatus 200 may also be referred to as a vacuum deposition apparatus. The vacuum deposition apparatus can be understood as an apparatus or configured for vacuum deposition of organic or inorganic materials including metallic materials, particularly for display manufacturing, e.g. for OLED display manufacturing.

[0039] In the present disclosure, a "vacuum deposition chamber" can be understood as a chamber configured for vacuum deposition. The term "vacuum", as used herein, can be understood in the sense of a technical vacuum having a vacuum pressure of less than, for example, 10 mbar. Typically, the pressure in a vacuum chamber as described herein may be between 10’5mbar and about 10’8mbar, particularly between 10’5mbar and 10-7mbar.

[0040] In the present disclosure, a “deposition source” can be understood as an arrangement or an assembly configured for material deposition on a substrate as described herein. In other words, the deposition source is configured for providing a source of material to be deposited on the substrate. For instance, the deposition source may have one or more crucibles configured to evaporate the source material to be deposited. A "crucible" can be understood as a device having a reservoir for the material to be evaporated by heating the crucible. Accordingly, a "crucible" can be understood as a source material reservoir, which can be heated to evaporate the source material into a gas by at least one of evaporation and sublimation of the source material. The crucible can include a heater to evaporate the source material in the crucible into a gaseous source material. For instance, initially the material to be evaporated can be in the form of a powder or a grain. The reservoir can have an inner volume for receiving the source material to be evaporated, e.g. organic or inorganic materials, e.g. metallic materials, such as lithium (Li), ytterbium (Yb), silver (Ag), and magnesium (Mg).

[0041] Further, the deposition source can have one or more distribution assemblies or distribution pipes configured for providing the evaporated material towards the substrate. For instance, a distribution tube or distribution pipe as described herein may provide a line source with a plurality of openings and / or nozzles which are arranged in lines along the length of the distribution tube. Accordingly, the distribution assembly can include a linear distribution showerhead, for example, having a plurality of openings, particularly nozzles (or an elongated slit) disposed therein. A showerhead as understood herein can have an enclosure, hollow space, or tube, in which the evaporated material can be provided or guided, for example from the evaporation crucible to the substrate. According to embodiments which can be combined with any other embodiments described herein, the length of the distribution pipe may correspond at least to the height of the substrate to be deposited. In particular, the length of the distribution pipe may be longer than the height of the substrate to be deposited, at least by 10% or even 20%. Accordingly, a uniformdeposition at the upper end of the substrate and / or the lower end of the substrate can be provided. For instance, the source material to be deposited may be an organic or inorganic material, e.g. a metallic material, for use as electrode materials or electron transport layer materials in organic light emitting diode (OLED) production.

[0042] According to embodiments which can be combined with any other embodiments described herein, the deposition apparatus is configured for material deposition in a substantially vertical orientation of the substrate. Accordingly, typically the vacuum deposition chamber 210 and the deposition source 220 are configured for material deposition on a substantially vertically arranged substrate 10.

[0043] In the present disclosure, a "substrate" can be understood as a material or object onto which material deposition is applied. In particular, the substrate can be a large area substrate as described herein. Typically, the substrate is of transparent material, e.g. transparent glass or transparent plastic.

[0044] According to some embodiments, large area substrates may have a size of 0.5 m2or larger, particularly of 1 m2or larger. For instance, the deposition apparatus may be adapted for processing large area substrates, such as substrates of GEN 4.5, which corresponds to about 0.67 m2of substrate (0.73x0.92m), GEN 5, which corresponds to about 1 .4 m2substrates (1.1 m x 1 .3 m), GEN 6, which corresponds to about 2.7 m2(1 .5 m x about 1 .8 m), GEN 7.5, which corresponds to about 4.29 m2substrates (1 .95 m x 2.2 m), GEN 8.5, which corresponds to about 5.7 m2substrates (2.2 m x 2.5 m), or even GEN 10, which corresponds to about 8.7 m2substrates (2.85 m x 3.05 m). Even larger generations such as GEN 11 and GEN 12 and corresponding substrate areas can similarly be implemented. According to yet further implementations, half sizes of the above-mentioned substrate generations can be processed.

[0045] According to embodiments, which can be combined with other embodiments described herein, the substrate thickness can be from 0.1 to 1 .8 mm. For example, the substrate thickness can be about 0.9 mm or below, such as 0.5 mm. The term “substrate” as used herein may particularly embrace substantially inflexible substrates, e.g., a glass plate, a plastic plate or other suitable substrates. However, the present disclosure is not limited thereto and the term “substrate” may also embrace flexible substrates such as a web or a foil. The term “substantially inflexible” is understood to distinguish over “flexible”. Specifically, a substantially inflexible substrate can have a certain degree of flexibility, e.g. a glass plate having a thickness of 0.9 mm or below, such as 0.5 mm or below, wherein the flexibility of the substantially inflexible substrate is small in comparison to the flexible substrates.

[0046] With exemplary reference to the block diagram shown in FIG. 11 , a method 300 of determining a thickness of a layer to be deposited on a substrate surface 11 of a substrate 10 is described. The method 300 includes moving (represented by block 310 in FIG. 11 ) a carrier 120 past at least one deposition source 220. The carrier 120 comprises at least one thickness gauge 110. A measurement surface 111 of the at least one thickness gauge 110 is positioned in a substrate plane 12 of the substrate surface 11 of the substrate 10. Additionally, the method 300 includes depositing (represented by block 320 in FIG. 11 ) material on the measurement surface 111 by the at least one deposition source 220. Further, the method 300 includes determining (represented by block 330 in FIG. 11 ) a thickness of the layer to be deposited on the substrate surface by evaluating the amount of material deposited on the measurement surface 111. Typically, the method 300 includes using (represented by block 340 in FIG. 11 ) a measurement system 100 according to any embodiments described herein.

[0047] Accordingly, in view of the embodiments describe herein, it is to be understood that compared to the state of the art, an improved measurement system, an improved deposition apparatus, an improved method ofdetermining a thickness of a layer to be deposited on a substrate surface of a substrate are provided. In particular, embodiments disclosed herein offer distinct advantages that enhance both efficiency and reliability. In particular, embodiments described herein provide for easy live tooling, such that it is easier to maintain repeatability specifications. Additionally, embodiments described herein are beneficially configured to provide instant feedback without delays, such that yield is enhanced and the time required for thickness measurements is reduced. Moreover, embodiments of the present disclosure beneficially eliminate the need for absolute thickness measurements, which has a positive effect on the efficiency and thus on the overall productivity.

[0048] While the foregoing is directed to embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

[0049] In particular, this written description uses examples to disclose the disclosure, including the best mode, and also to enable any person skilled in the art to practice the described subject-matter, including making and using any devices or systems and performing any incorporated methods. While various specific embodiments have been disclosed in the foregoing, mutually non-exclusive features of the embodiments described above may be combined with each other. The patentable scope is defined by the claims, and other examples are intended to be within the scope of the claims if the claims have structural elements that do not differ from the literal language of the claims, or if the claims include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

WHAT IS CLAIMED:1 . A measurement system (100) for determining a thickness of a layer to be deposited on a substrate surface (11 ) of a substrate (10), comprising at least one thickness gauge (110) coupled to a carrier (120), wherein a measurement surface (111 ) of the at least one thickness gauge (110) is positioned in a substrate plane (12) of the substrate surface (11 ) of the substrate (10).

2. The measurement system (100) of claim 1 , wherein the at least one thickness gauge (110) comprises a plurality of thickness gauges (110) provided at different vertical positions and / or different horizontal positions in the substrate plane (12).

3. The measurement system (100) of claim 1 or 2, further comprising a shutter (130) configured to cover the measurement surface (111 ), particularly wherein the shutter (130) is a movable shutter.

4. The measurement system (100) of claim 3, wherein the shutter (130) is a plate, particularly a disk, having at least one measurement opening (131 ), particularly wherein the shutter (130) is rotatable around a shutter rotation axis (131 ) being perpendicular to the measurement surface (111 ).

5. The measurement system (100) of any of claims 1 to 3, wherein the at least one thickness gauge (110) comprises at least one group (112) of thickness gauges coupled to a common movable support (140), particularly wherein the common movable support (140) is rotatable around a rotation axis (141 ) being perpendicular to the measurement surface (111 ).

6. The measurement system (100) of claim 5, wherein the at least one group (112) of thickness gauges comprises a plurality of groups of thickness gauges, wherein individual groups of thickness gauges are coupled to individual common movable supports.

7. The measurement system (100) of claim 6, wherein the individual common movable supports are rotatable around different rotation axes being perpendicular to the measurement surface (111 ).

8. The measurement system (100) of any of claims 1 to 7, wherein the at least one thickness gauge (110) comprises a piezoelectric resonator.

9. The measurement system (100) of any of claims 1 to 8, wherein the carrier (120) comprises a power supply (150), particularly a battery, connected to the at least one thickness gauge (110).

10. The measurement system (100) of claim 9, wherein the power supply (150) is connected to a first actuator (161 ) to move, particularly to rotate, the shutter (130) according to claim 3 or 4.11 . The measurement system (100) of claim 9 or 10, wherein the power supply (150) is connected to a second actuator (162) to move, particularly to rotate, the common movable support (130) according to claim 5.

12. The measurement system (100) of any of claims 1 to 11 , further comprising an evaluation unit (170), wherein the evaluation unit (170) is coupled to the carrier (120), or wherein the evaluation unit (170) is decoupled from the carrier (120), particularly wherein the evaluation unit (170) is provided at a specific position within a deposition apparatus (200) in which the carrier (120) is employed.

13. The measurement system (100) of any of claims 1 to 12, further comprising at least one heater (180) to heat the at least one thickness gauge (110), particularly the measurement surface (111 ) of the at least one thickness gauge (110).

14. A deposition apparatus (200) for depositing material on a substrate (10), comprising:- a vacuum deposition chamber (210)- at least one deposition source (220) provided inside the vacuum deposition chamber (210); and- a measurement system (100) according to any of claims 1 to 13.

15. A method (300) of determining a thickness of a layer to be deposited on a substrate surface (11 ) of a substrate (10), comprising:- moving (310) a carrier (120) past at least one deposition source (220), wherein the carrier comprises at least one thickness gauge (110), wherein a measurement surface (111 ) of the at least one thickness gauge (110) is positioned in a substrate plane (12) of the substrate surface (11 ) of the substrate (10),- depositing (320) material on the measurement surface (111 ) by the at least one deposition source (220); and- determining (330) a thickness of the layer to be deposited on the substrate surface by evaluating the amount of material deposited on the measurement surface.

16. The method (300) of claim 15, comprising using (320) a measurement system (100) according to any of claims 1 to 13.

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