CN108699682B

CN108699682B - Method for checking gas separation quality of gas separation channel in vacuum chamber, and vacuum processing apparatus

Info

Publication number: CN108699682B
Application number: CN201680081469.XA
Authority: CN
Inventors: 沃尔夫冈·布什贝克; 于尔根·亨里奇; 托马斯·格比利
Original assignee: Applied Materials Inc
Current assignee: Applied Materials Inc
Priority date: 2016-02-19
Filing date: 2016-02-19
Publication date: 2020-12-22
Anticipated expiration: 2036-02-19
Also published as: JP6800236B2; JP2019507251A; CN108699682A; KR20180110129A; WO2017140384A1; TWI646213B; TW201736637A; KR102180420B1

Abstract

According to one aspect of the present disclosure, a method of checking a gas separation quality of a gas separation channel (20) extending between a first vacuum processing zone (10) and at least one second vacuum processing zone (12) in a vacuum chamber (2) is provided, wherein the gas separation channel (20) is configured as a passage for a substrate while reducing a gas flow from the first vacuum processing zone (10) into the at least one second vacuum processing zone (12). The method comprises the following steps: introducing a test gas (31) into the first vacuum processing zone (10); and measuring a first content (33) of the test gas in the background gas in the at least one second vacuum processing region (12). According to a second aspect, a vacuum treatment apparatus (1) and a vacuum deposition apparatus (100,500) for performing the method are provided.

Description

Method for checking gas separation quality of gas separation channel in vacuum chamber, and vacuum processing apparatus

Technical Field

Embodiments of the present disclosure relate to thin film processing devices, particularly to deposition systems, and more particularly to roll-to-roll (R2R) deposition systems and methods for operating the same. Embodiments of the present disclosure relate particularly to gas separation in a roll-to-roll deposition system, and more particularly to a method of checking the quality of gas separation between two or more vacuum processing zones in a vacuum processing apparatus (e.g., in a roll-to-roll deposition system). In particular, embodiments disclosed herein relate to a method of inspecting gas separation quality of a gas separation channel extending between a first vacuum processing region and a second vacuum processing region in a vacuum chamber, and a vacuum processing apparatus and a vacuum deposition apparatus for substrate processing having improved gas separation characteristics.

Background

The processing of flexible substrates (e.g., plastic films or foils) is highly desirable in the packaging industry, the semiconductor industry, and other industries. Processing may include coating the flexible substrate with a desired material (e.g., metal). Systems for performing this task generally include a processing drum (e.g., a cylindrical roller) coupled to the processing system for transporting the substrate and at least a portion of the substrate being processed on the processing drum. A roll-to-roll coating system can provide a high throughput system.

Generally, a thin metal layer may be deposited using an evaporation process, such as a thermal evaporation process, and may be metallized onto the flexible substrate. However, the demand for roll-to-roll deposition systems in the display industry and Photovoltaic (PV) industry has also increased dramatically. For example, touch panel elements, flexible displays, and flexible PV modules have resulted in an increasing need to deposit suitable layers in roll-to-roll coaters, particularly with low manufacturing costs. Such devices typically have several layers that can be fabricated using Chemical Vapor Deposition (CVD) processes and, in particular, using Plasma Enhanced Chemical Vapor Deposition (PECVD) processes.

The combination of several CVD, PECVD and/or Physical Vapor Deposition (PVD) sources working with different gas mixtures and/or different working pressures in a vacuum chamber faces the need for a good separation of the process gases to avoid cross-contamination effects in the subsequent processing and to ensure long-term process stability. For example, a first process gas may be used in a first vacuum processing region and a second process gas may be used in a second, adjacent vacuum processing region. A good gas separation factor between the first and second vacuum processing regions may be beneficial not only to avoid contamination of the second material layer on the substrate by particles of the first material, but also to avoid undesired chemical reactions between the first and second materials.

In some roll-to-roll coating systems, the vacuum processing areas (e.g., the sputtering compartments) may be separated by a slit that follows the curvature of the coating drum. The gas separation strongly depends on the geometrical arrangement of the gas separation channel between the coating drum and the gas separation unit. A good gas separation factor may be achieved when the gas separation channel comprises a slit with a small slit width, which still allows the substrate to be transported through the slit. The slit width may depend on the adjustment of the gas separation unit, the thickness of the substrate, and the temperature of the coating drum.

Therefore, it may be reasonable to check the gas separation channel frequently in order to ensure that the process gas flow through the gas separation channel is low, but that the substrate still passes through the gas separation channel. Conventional geometric measurements of gas separation channels may be inadequate.

In view of the above, it is desirable to provide a reliable method of checking the gas separation quality of a gas separation channel extending between vacuum processing zones in a vacuum chamber so that the gas separation channel can be suitably adjusted.

Disclosure of Invention

In view of the above, a method of checking gas separation quality of a gas separation channel in a vacuum chamber is provided. Further, a vacuum processing apparatus, a vacuum deposition apparatus, and a method of operating a vacuum deposition apparatus are provided.

According to one aspect of the present disclosure, a method of inspecting gas separation quality of a gas separation channel extending between a first vacuum processing zone and at least one second vacuum processing zone in a vacuum chamber is provided, wherein the gas separation channel is configured as a passage for a substrate while reducing gas flow between the vacuum processing zones. The method includes introducing a test gas into a first vacuum processing region; and measuring a first content of the test gas in the background gas in the at least one second vacuum processing region.

According to a further aspect, a vacuum treatment apparatus is provided, in particular for performing the method disclosed herein. The vacuum processing apparatus includes: a vacuum chamber; a first vacuum processing region, at least one second vacuum processing region, and a gas separation channel extending between the first vacuum processing region and the at least one second vacuum processing region, wherein the gas separation channel is configured for passage of a substrate while reducing gas flow from the first vacuum processing region into the at least one second vacuum processing region; a first gas inlet for introducing a test gas into the first vacuum processing region; and a test gas sensor configured to measure a first content of the test gas in the background gas in the at least one second vacuum processing region.

According to a further aspect, a vacuum deposition apparatus is provided, in particular for performing the method disclosed herein. The vacuum deposition apparatus includes: a vacuum chamber; and a first vacuum processing zone and at least one second vacuum processing zone arranged in a vacuum chamber; a first deposition source disposed in the first vacuum processing region and configured for depositing a thin layer of a first material on the substrate, and a second deposition source disposed in the at least one second vacuum processing region and configured for depositing a thin layer of a second material on the substrate; a substrate support having a substrate support surface for guiding a substrate along a gas separation channel from a first vacuum processing zone to at least one second vacuum processing zone or vice versa; a first gas inlet for introducing a test gas into the first vacuum processing region; and a test gas sensor configured to measure a first content of the test gas in the background gas in the at least one second vacuum processing region.

In some embodiments, the vacuum deposition apparatus is a roll-to-roll deposition system, in particular a roll-to-roll deposition system comprising at least one CVD deposition source.

According to yet another aspect, a method of operating a vacuum deposition apparatus is provided, the method comprising checking a gas separation quality of a gas separation channel arranged between a first vacuum processing region and at least one second vacuum processing region in a vacuum chamber, wherein the gas separation channel is configured as a passage for a substrate while reducing a gas flow from the first vacuum processing region into the at least one second vacuum processing region, wherein a test gas is introduced into the first vacuum processing region and a first content of the test gas in a background gas present in the at least one second vacuum processing region is measured; the method further comprises the following steps: adjusting the gas separation channel according to the measured content; directing the substrate from the first vacuum processing region to at least one second vacuum processing region along a gas separation channel; and depositing a first material film on the substrate in the first vacuum processing region and depositing a second material film on the substrate in at least one second vacuum processing region.

Other aspects, advantages, and features of the disclosure are apparent from the appended claims, description, and drawings.

Drawings

So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to embodiments. The drawings relate to embodiments of the present disclosure and are described below. Exemplary embodiments are illustrated in the accompanying drawings and described in the following detailed description.

Fig. 1 shows a schematic cross-sectional view of a vacuum processing apparatus for processing of substrates according to embodiments described herein, operable according to the methods described herein for checking the gas separation quality of gas separation channels;

fig. 2 depicts a schematic cross-sectional view of a vacuum processing apparatus for processing of substrates according to embodiments described herein, operable according to the methods described herein for checking gas separation quality of gas separation channels;

FIG. 3 depicts a schematic view of a roll-to-roll deposition apparatus operable according to the methods described herein for inspecting gas separation quality of a gas separation channel, according to embodiments described herein;

FIG. 4 depicts a schematic view of a roll-to-roll deposition apparatus operable according to the methods described herein for inspecting gas separation quality of a gas separation channel, according to embodiments described herein;

FIG. 5 is a schematic diagram illustrating various gas flows in a vacuum processing apparatus when operating in accordance with the methods described herein;

FIG. 6 is a cross-sectional view of a roll-to-roll hot wire Chemical Vapor Deposition (CVD) apparatus (HWCVD system) for operation according to methods described herein;

FIG. 7 is a flow chart of a method of inspecting gas separation quality of a gas separation channel according to embodiments described herein; and

fig. 8 shows a flow chart of a method of operating a vacuum deposition apparatus for depositing a thin film on a substrate according to embodiments described herein.

Detailed Description

Reference will now be made in detail to the various embodiments, one or more examples of which are illustrated in each figure. The various examples are provided by way of explanation and are not meant as limitations. 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. The present disclosure is intended to embrace these modifications and variations.

In the following description of the drawings, the same reference numerals are used for the same or similar parts. In general, only the differences with respect to the individual embodiments are described. Unless otherwise indicated, descriptions of a portion or aspect in one embodiment also apply to a corresponding portion or aspect in another embodiment.

Fig. 1 shows a vacuum processing apparatus 1 for processing of a substrate, such as a flexible substrate, e.g. a web, according to embodiments described herein. The vacuum processing apparatus 1 includes a vacuum chamber 2, a first vacuum processing region 10 in the vacuum chamber 2, and a second vacuum processing region 12 in the vacuum chamber 2. The vacuum chamber 2 is provided such that a vacuum (i.e. a pressure below atmospheric pressure, for example a pressure below 10mbar or below 1mbar) can be created in the vacuum chamber 2. Various vacuum processing techniques, particularly vacuum deposition techniques, may be used to process the substrate, such as depositing a thin film on the substrate.

As used herein, "a passage for a substrate" may mean a channel, such as an opening or slit between two vacuum processing regions, having dimensions suitable for guiding a substrate from a first vacuum processing region to a second vacuum processing region, and/or vice versa. The substrate may be a thin substrate, such as a film or web having a thickness of less than 1mm or less than 0.5 mm. Accordingly, the dimension of the via in the thickness direction of the substrate may be small, for example, 2mm or less, 1mm or less, or 0.5mm or less. The passage may be formed between a substrate support for guiding the substrate and a wall of the vacuum processing region. In some embodiments, the lateral dimension of the via may substantially correspond to the lateral dimension of the substrate. For example, the transverse dimension of the via may be 30cm or more, or 1m or more.

The "background gas" in one of the vacuum processing regions may be defined as the gas present in the respective vacuum processing region. The background gas may, for example, consist of a separation gas (e.g. an inert gas), a process gas, a test gas, a purge gas and/or further residual gas components. When performing the methods described herein, the background gas may primarily comprise a separation gas.

As used herein, "vacuum processing region" may mean a region within the main volume of a vacuum chamber that may be used to process a substrate, wherein processing may include contacting a surface of the substrate with a process gas. The vacuum processing zone may be separated from the main volume of the vacuum chamber by a wall section, but may still be in communication with the main volume via a gas separation channel. The vacuum processing region may be defined at least in part by a source housing of a deposition source disposed in a vacuum chamber.

The vacuum processing technique may include introducing a first process gas into the first vacuum processing region 10 such that the first process gas may chemically or physically react with the substrate. Further, the vacuum processing technique may include introducing a second process gas into the second vacuum processing region 12 such that the second process gas may chemically or physically react with the substrate. The second process gas may be different from the first process gas. In many cases, gas separation between the first and second vacuum processing regions should be considered in order to avoid undesired chemical reactions between the different process gases and/or in order to avoid contamination of the first material layer on the substrate with the second material component, or vice versa.

The process gas may include at least one or more of the following gases: precursor gases, reaction gases, inert gases, etching gases, gases for depositing a film on a substrate via at least one of Chemical Vapor Deposition (CVD), Physical Vapor Deposition (PVD), Plasma Enhanced Chemical Vapor Deposition (PECVD), sputtering, HWCVD, or similar deposition techniques, gases to etch a deposited layer, and gases to dope a deposited layer.

Fig. 1 depicts the first vacuum processing zone 10 and the second vacuum processing zone 12 separated by one or more separating walls. A gas separation channel 20 is disposed between the first vacuum processing region 10 and the second vacuum processing region 12, the gas separation channel 20 being configured as a passage for the substrate. Thus, the substrate may be first processed in the first vacuum processing region 10, transferred to the second vacuum processing region 12 along the gas separation passage, and then processed in the second vacuum processing region 12. However, the gas separation channels 20 may allow gas flow between vacuum processing regions. Thus, the gas separation channels 20 may be configured such that gas flow between vacuum processing regions is reduced while still allowing substrates to be transferred between vacuum processing regions. For example, the width of the slit 21 of the gas separation channel 20 shown in fig. 1 may be 5mm or less, particularly 2mm or less.

For example, in CVD roll-to-roll web coating systems, gas separation plays a major role when utilizing processing techniques with high gas loads in the vacuum processing region. The operating pressure in at least one of the vacuum treatment zones may be in the mbar range, for example between 0.1 and 5mbar, in particular about 1 mbar.

Gas separation may be improved by using a separation gas flow, thereby avoiding the flow (diffusion) of undesired species of individual process gases through the gas separation channel into adjacent vacuum processing regions. However, separating the gases further increases the background pressure in the individual vacuum processing zones.

To ensure good properties of the deposited film, twoThe quality of the gas separation between or among the vacuum processing regions can be frequently checked or inspected. By measuring the (total) pressure increase in the second vacuum treatment zone when gas is introduced into the first vacuum treatment zone, it may be made at low background pressures (e.g. below 10 a)^-3Background pressure of mbar) it becomes possible to check the individual gas separation factors or vice versa. However, total pressure measurement can be difficult when several orders of magnitude of gas separation factor needs to be measured while the background pressure is in the mbar range (e.g. greater than 0.1 mbar).

According to the method of checking the gas separation quality of a gas separation channel 20 described herein, a test gas 31 is introduced into a first vacuum processing zone 10 and a first content 33 of the test gas in a background gas 32 present in at least one second vacuum processing zone 12 is measured. In some embodiments, the measurements are performed inside the vacuum chamber, for example via a test gas sensor operable under vacuum conditions. In some embodiments, the measurements are performed outside of the vacuum chamber (e.g., in an exhaust line of a vacuum pump configured for pumping gas out of the individual vacuum processing regions), such as via a test gas sensor operable at atmospheric conditions. In other words, the content of the test gas in the background gas 32 does not have to be measured inside the second vacuum processing region, but the background gas 32 may be directed outside the vacuum chamber where the measurement of the content of the test gas can be performed.

Wherein the first vacuum processing zone and the second vacuum processing zone are interchangeable. In other words, the method may alternatively or additionally include introducing a test gas 31 into the second vacuum processing region 12 and measuring the content of the test gas present in the first vacuum processing region 10.

Measuring the first amount 33 of the test gas may include measuring a first amount (e.g., in parts per million) of the test gas in the background gas 32 measured from the second vacuum processing region 12. For example, the background gas 32 is pumped out of the second vacuum processing region 12, so a first amount 33 of the test gas in the background gas is measured. The measured content in the exhaust line of the vacuum pump may correspond to the content (e.g. in ppm) inside the second vacuum treatment zone 12.

In some embodiments, measuring the first content 33 of the test gas includes measuring at least one of a concentration, a partial pressure, a molecular density (molecules/volume), and a mole fraction of the test gas in the background gas 32 in the second vacuum processing region 12. In some embodiments, the (absolute) pressure in the second vacuum processing region may also be measured. Based on the (absolute) pressure in the second vacuum processing region and the first content 33 of the test gas in the background gas 32, the partial pressure and/or concentration of the test gas in the second vacuum processing region 12 can be determined.

The gas separation quality of the gas separation channel may be defined as insufficient if the determined first content 33 of the test gas in the second vacuum processing region (e.g. expressed in ppm with respect to the background gas 32) is above a predetermined threshold. In this case, the gas separation channel may be adjusted, for example, by at least one of adjusting the slit width of the gas separation channel, modifying the flow of the separated gas in the gas separation channel, modifying the vacuum pumping rate of one or more vacuum pumps connected to the vacuum chamber or vacuum processing region.

The first content 33 of the test gas may be measured by a test gas sensor 50 (i.e., a sensor specifically configured for measuring the test gas). This is because simultaneous analysis of various gases that may be present in the background gas 32 in the second vacuum processing region 12, for example by a Residual Gas Analyzer (RGA) at high background pressures above 0.1mbar, may be insufficiently sensitive or may output unrealistic values. In particular, it can be difficult to operate residual gas analyzers at high background pressures. On the other hand, a particular test gas sensor 50 specifically configured for measuring a test gas may be highly sensitive and may be operable at high background pressures (e.g., at background pressures of 0.1mbar or more, or 1mbar or more).

If the measured content 33 of the test gas is below a predetermined threshold, the gas separation quality may be defined as sufficient and the vacuum processing system may be used for processing the substrate.

According to the methods described herein, particularly by using a particular test gas sensor, very small contents (e.g., in parts per million) or very small partial pressures of a particular test gas at background pressures (which can be up to 5 orders of magnitude higher) can be measured.

In some embodiments described herein, sensors with very high sensitivity for a particular test gas are used. For example, in some embodiments, which can be combined with other embodiments described herein, an optical or spectroscopic test gas sensor can be used.

For example, a test gas sensor may include a light source and a light detector, and may measure a spectral characteristic of the test gas (e.g., absorption of a characteristic wavelength by the test gas). Specifically, the test gas sensor may have an infrared source, a measurement chamber, an interference filter (interference filter), and an infrared detector. The gas to be examined, including the test gas, may pass through the measurement chamber and the light absorbed by the gas may be measured. The filter may be located in front of the light detector and may be configured to prevent wavelengths outside the specific wavelength for the test gas from passing to the detector. The light intensity may be detected by a detector and may be converted to a test gas content value, such as a test gas concentration value. For example, the volumetric concentration of the test gas may be measured.

In some embodiments, the test gas sensor can be an infrared gas sensor. Alternatively or additionally, a chemical gas sensor or other gas sensor configured for measuring a first content of a test gas may be used.

The test gas 31 may be introduced into the first vacuum processing region 10 via the first gas inlet 30, and the first gas inlet 30 may be a process gas inlet of the first vacuum processing region 10. Thus, when checking the gas separation quality, operating conditions can be simulated, which may lead to reliable test results. Specifically, the test gas may be introduced into the first vacuum processing region 10 at a predetermined test gas flow rate, which may be a constant flow rate. The test gas may be introduced over a time interval of several seconds (e.g., 10 seconds or more), and more particularly for several minutes (particularly 5 minutes or more), until a substantially steady gas flow rate may be established in the vacuum chamber and/or in the exhaust line between the vacuum processing regions. In particular, the operating conditions during deposition may deviate substantially from the conditions in a closed apparatus, particularly when high gas loads are used during operation, for example, between CVD vacuum processing regions. The methods described herein provide reliable measurements of separation quality as operating conditions can be simulated.

Operating conditions can be further simulated by using a test gas having characteristics similar to those of the process gas to be used during operation (e.g., during thin film deposition). For example, the molecular weight of the test gas may be similar to the molecular weight of the process gas to be used during operation of the vacuum processing apparatus. Alternatively or additionally, the volatility of the test gas may be similar to the volatility of the process gas to be used. In some embodiments, which can be combined with other embodiments described herein, the test gas has a molecular mass of 5g/mol or more and 500g/mol or less, in particular 20g/mol or more and 100g/mol or less. More specifically, the molecular weight of the test gas may be between 40 and 50 g/mol.

For example, in some cases, helium may be too volatile to provide reliable results. In particular, using helium as a test gas may work in principle, but may output too conservative a value due to the small molecular size and/or weight of helium.

In some embodiments, which can be combined with other embodiments described herein, the test gas is CO₂A gas. Further, the first content 33 of the test gas may be via CO₂Sensor measurement, in particular via optical or spectroscopic CO₂And (6) measuring by a sensor.

By using CO₂The use of a gas as the test gas 31 provides the following advantages: for measuring CO₂Sensors having a high sensitivity of 3ppm or better are commercially available. In a typical vacuum processing apparatusCO in₂The background pressure is low, so that the pre-existing CO is₂The molecules do not negatively affect the measurement results. CO 2₂Are non-toxic and are commonly used. CO 2₂It works for optical measurement systems, while sensors for other gases can only operate in the presence of oxygen. In addition, CO₂The properties of the gas may be similar to those of typically used process gases. CO 2₂The test gas results in a very reliable measurement result, so that the separation quality of the gas separation channel can be determined in a very accurate manner.

In some embodiments, CO may be used₂Other gases are used as the test gas, particularly non-toxic gases that are commercially available and generally not present in large quantities in the vacuum processing chamber.

The first content 33 of the test gas may be measured in an exhaust line 41 of a vacuum pump 42, the exhaust line 41 of the vacuum pump 42 being connected to the at least one second vacuum processing region. For example, the test gas sensor may be disposed in or near an exhaust line 41 of a vacuum pump 42, the exhaust line 41 of the vacuum pump 42 being configured for pumping the interior volume of the second vacuum processing region 12. This is because the composition of the exhaust gas pumped through the exhaust line 41 may accurately or substantially correspond to the composition of the gas present in the second vacuum processing region 12. For example, the second vacuum processing region 12 may include a pumping outlet connected to the vacuum pump 42 such that the second vacuum processing region 12 may be pumped directly.

During normal processing operations of the vacuum processing apparatus, a purge gas (e.g., an inert gas) may be provided in the vacuum pump in order to avoid undesirable chemical reactions of reactive process gases that may potentially flow through the vacuum pump at the same time. When testing the first content 33 of the gas in the exhaust line 41 of the vacuum pump according to the method described herein, the purge gas supply may be turned off. This is because the purge gas in the vacuum pump may negatively affect the measurement accuracy.

Measuring the first content 33 of the test gas in the exhaust line 41 may have the further advantage that the sensitivity of the test gas sensor 50 may depend on the absolute gas pressure. Therefore, it may be advantageous to arrange the test gas sensor 50 at atmospheric pressure.

As shown in fig. 1, a test gas 31 may be introduced into the first vacuum processing region 10 via a first gas inlet 30 (e.g., via a process gas inlet). The first vacuum processing region 10 may be pumped by a first region vacuum pump 43 connected to the interior volume of the first vacuum processing region 10. A major portion of the test gas 31 in the first vacuum processing region 10 may be pumped by the first zone vacuum pump 43 and only a small portion of the test gas may diffuse along the gas separation channel 20 into the second vacuum processing region 12.

As further shown in fig. 1, the gas separation channel 20 may be at least partially configured as a slit 21 between a gas separation wall 22 and a substrate support 80, the substrate support 80 being configured for supporting a substrate. In some embodiments, the width of the slit 21 may be adjustable, for example, according to the temperature of the substrate support 80 and/or according to the thickness of the substrate to be conveyed along the gas separation channel 20. In some embodiments, the width of the slit 21 may be in the range of several millimeters, such as 5mm, 2mm, 1mm, or less.

A portion of the test gas entering the second vacuum processing region 12 may be pumped by a vacuum pump 42 connected to the interior volume of the second vacuum processing region 12. The first content 33 of the test gas in the background gas 32 of the second vacuum processing region 12 may be measured by a test gas sensor 50, which test gas sensor 50 is arranged in the exhaust line 41 of the vacuum pump 42.

Fig. 2 depicts a schematic view of a vacuum processing apparatus 5 according to embodiments described herein. The vacuum processing apparatus 5 is substantially similar to the vacuum processing apparatus 1 shown in fig. 1, and thus reference is made to the above description and the detailed description is omitted.

The vacuum treatment device 5 as shown in fig. 2 comprises a vacuum chamber 2, wherein a first vacuum treatment zone 10 and a second vacuum treatment zone 12 are arranged in the vacuum chamber 2. A gas separation unit to reduce gas flow between vacuum processing zones is provided. The substrate may be transferred between the first vacuum processing region 10 and the second vacuum processing region 12 along the gas separation channel 20. The gas separation channel may be provided at least in part as a slit between the substrate support 80 and a gas separation unit comprising the gas separation wall 22. Different arrangements of the gas separation units and different arrangements of the gas separation channels 20 are possible.

In some embodiments, the first vacuum processing region 10 is pumped by a first region vacuum pump 43 and the second vacuum processing region 12 is pumped by a second region vacuum pump 42. A test gas sensor 50 is provided to measure a first amount 33 of the test gas in the background gas of the second vacuum processing region 12 and a second test gas sensor 51 is provided to measure a second amount 34 of the test gas in the second background gas 35 of the first vacuum processing region 10. The measuring of the second content 34 of the test gas may include measuring a second content of the test gas in a second background gas 35 taken from or pumped from the first vacuum processing region 10. Reference may be made to the above explanation regarding the measurement of the first content 33 of the test gas in the background gas 32 present in the second vacuum processing region 12.

In some embodiments, which can be combined with other embodiments described herein, a test gas sensor 50 is provided in the exhaust line 41 of the second zone vacuum pump 42 or near the exhaust line 41 of the second zone vacuum pump 42 for measuring the test gas content in the exhaust gas pumped from the second vacuum processing zone. A second test gas sensor 51 may be provided in or near the exhaust line of the first zone vacuum pump 43 for measuring the test gas content in the exhaust gas pumped from the first vacuum processing zone. The content of the test gas in the exhaust gas flow flowing through the respective exhaust line may be measured.

In some embodiments, which can be combined with other embodiments described herein, the test gas 31 is introduced into the first vacuum processing region 10 (e.g., at a fixed flow rate). Then, for example, after waiting for 5 minutes or more, the first content 33 is measured by the test gas sensor 50, and the second content 34 is measured by the second test gas sensor 51. The first content 33 may be compared to the second content 34. For example, the ratio between the second content 34 and the first content 33 may be calculated, for example, by calculating a ratio between the respective partial pressures or contents (in parts per million) of the test gas in the first and second vacuum processing zones.

A larger ratio between the second content 34 and the first content 33, for example larger than 10,000, in particular larger than 100,000, may indicate a good gas separation quality. In other words, a high separation factor of more than 10,000 or more than 100,000 is advantageous. In some embodiments, the gas separation channel can be tuned when the ratio is less than 100,000 or less than 10,000. In some embodiments, for example when the background gas pressures in the first and second vacuum processing regions are approximately equal, no more than 1 molecule of test gas should be present in the second vacuum processing region for every 100,000 molecules of test gas present in the first vacuum processing region. Otherwise, the gas separation channel may be readjusted.

In a similar manner, the gas separation quality may be measured in the opposite direction, i.e. from the second vacuum processing zone 12 into the first vacuum processing zone 10. In this case, the test gas may be introduced into the second vacuum processing region 12, for example, via the second gas inlet 36, which second gas inlet 36 may be a process gas inlet of the second vacuum processing region 12. In this case, the second content 34 of the test gas present in the first vacuum processing region may be measured via the second test gas sensor 51.

In some embodiments, more than two vacuum processing zones may be arranged in the vacuum chamber 2, for example three, four or more vacuum processing zones may be arranged adjacent to each other along the transport direction of the substrate. The vacuum processing regions may be connected via gas separation channels, similar to the gas separation channels 20 described with reference to fig. 1. More than two, in particular all, of the vacuum processing zones may be provided with test gas sensors to measure the test gas in the respective vacuum processing zone. The gas separation quality of the respective gas separation channels between adjacent vacuum processing regions can then be checked in a similar manner. Where appropriate, the overall gas separation quality of the vacuum processing apparatus may be monitored and modified.

In some embodiments, which can be combined with other embodiments described herein, a main chamber test gas sensor 52 is provided to measure the content of the test gas in the background gas of the main volume 3 of the vacuum chamber 2. For example, the main chamber test gas sensor 52 may be disposed in the exhaust line of the main chamber vacuum pump.

According to some embodiments, which can be combined with other embodiments described herein, a separation gas 60 is introduced into the gas separation channel 20 between the first vacuum processing zone 10 and the second vacuum processing zone 12. The one or more separation gas inlets 61 for introducing separation gas into the gas separation channel 20 may be arranged such that in at least a portion of the gas separation channel 20, a first main flow direction of the separation gas 60 is opposite to a second main flow direction of the test gas. When operating the vacuum processing apparatus 5, the quality of the separation between the vacuum processing regions can be improved by introducing a separation gas.

As already indicated above, when performing the method according to embodiments described herein, the operating conditions may be simulated in order to achieve a reliable indication of the gas separation quality. Therefore, it may be advantageous to measure the first content 33 of the test gas when the separation gas 60 is introduced into the gas separation channel 20. Typical separation gases, in particular inert gases, such as N, can be used₂. In some embodiments, the flow rate of the separated gas in the gas separation channel may correspond to a typical flow rate under operating conditions. The separation gas flow rate may be higher than the test gas flow rate, e.g., 10 times, 100 times, or more higher.

The separation gas 60 may be introduced at more than one separation gas inlet 61. For example, a first separation gas inlet may be disposed in a sidewall of the first vacuum processing region 10, and a second separation gas inlet may be disposed in a sidewall of the second vacuum processing region 12.

As shown in fig. 2, in some embodiments, the gas separation channel 20 may be open to the main volume 3 of the vacuum chamber 2 in at least one section between the first vacuum processing zone 10 and the second vacuum processing zone 12, for example in a central section 25 between two slit sections.

The separation quality can be further improved by pumping from a main pumping outlet 70 connected to the main volume 3 of the vacuum chamber 2. Since the gas separation channel 20 is at least partially open to the main volume 3, a major part of the test gas flowing along the gas separation channel 20 will be pumped by a main chamber vacuum pump 71, said main chamber vacuum pump 71 being connected to the main pumping outlet 70. Only a small portion of the test gas will enter the second vacuum processing region 12.

When performing the method according to embodiments described herein, the first pressure in the first vacuum treatment zone 10 and/or the second vacuum treatment zone 12 may be maintained in a range between 0.1mbar and 2mbar, in particular about 1 mbar. The background pressure may be adjusted by modifying the test gas flow rate, by modifying the separation gas flow rate, and/or by modifying the vacuum pumping rate. Furthermore, the geometrical arrangement of the gas separation channel, such as the width of the slit 21, may be adjusted. In particular in CVD systems, a pressure of 0.1mbar or more may correspond to the pressure in the vacuum processing region during operation of the vacuum processing apparatus (e.g., during thin film deposition).

In some embodiments, the separation quality may be further improved by maintaining the first pressure at a level higher than the second pressure in the main volume 3 of the vacuum chamber 2. In this case, gas flowing through the gas separation channel 20 tends to enter the main volume 3 of the vacuum chamber where it is pumped away by the main chamber vacuum pump 71.

As further shown in fig. 2, the gas separation channel 20 may comprise a first slit separating the first vacuum processing region 10 and the main volume 3 of the vacuum chamber 2, a central section 25, which is open to the main volume 3 of the vacuum chamber 2, and a second slit separating the main volume 3 and the second vacuum processing region 12. In some embodiments, a main pumping outlet 70 is provided for pumping the main volume 3 of the vacuum chamber 2.

Fig. 3 shows a schematic cross-sectional view of a roll-to-roll deposition system in which the above-described method may be performed. The roll-to-roll deposition system is configured as a vacuum deposition apparatus 100 for depositing thin films on a substrate 106 in at least a first vacuum processing region 10 and a second vacuum processing region 12.

Similar to the above-described embodiment, the vacuum processing regions are separated from each other by at least one gas separation unit, wherein a gas separation channel 20 configured to serve as a passage for the substrate 106 is disposed between the vacuum processing regions. The arrangement of the gas separation channel 20 and the vacuum processing region may correspond to the arrangement in the above-described embodiment, so that the above description may be referred to without redundancy.

The substrate 106 processed in the vacuum deposition apparatus 100 disclosed herein may be a flexible substrate, such as a web substrate. The flexible substrate or web may be characterized as bendable. For example, a web as described in embodiments herein may be a foil or another flexible substrate. However, as described in more detail below, the advantages of the embodiments described herein may also be provided to non-flexible substrates or carriers of other in-line deposition systems. Thus, curved or convex substrate supports (e.g., the rotatable coating drum 110 shown in FIG. 3), or planar substrate supports 80 (e.g., the planar transport device shown in FIG. 2) may be used. Furthermore, the substrate support need not be movable, and the substrate may be moved between vacuum processing zones by other means.

The vacuum deposition apparatus 100 shown in fig. 3 includes a vacuum chamber 101. Various vacuum deposition techniques may be used to process the substrate 106 or to deposit thin films on the substrate. As shown in fig. 3 and referenced herein, the vacuum deposition apparatus 100 may be a roll-to-roll deposition apparatus that supports a flexible substrate 106 that is guided and processed. However, according to some embodiments, which can be combined with other embodiments described herein, the aspects, details, and features of gas separation described herein can also be applied to other deposition apparatuses in which a glass substrate, a wafer, or another substrate, which may also be inflexible, or may be provided in an inflexible carrier, is processed.

The flexible substrate 106 in fig. 3 is guided into the vacuum chamber 101 as indicated by arrow X. For example, the flexible substrate 106 may be directed into the vacuum chamber 101 from an unwinding station. The flexible substrate is guided by the rollers 104 to a coating drum 110, which coating drum 110 is configured for supporting the substrate during processing and/or deposition. As shown in fig. 3, particularly for roll-to-roll deposition devices, the substrate support may be a coating drum that is rotatable about a drum shaft 111. The substrate 106 is guided from the coating drum to the further rollers 104 and leaves the vacuum chamber 101 as indicated by the second arrow X.

The embodiment illustrated in fig. 3 includes a first deposition source 130 and a second deposition source 131, the first deposition source 130 being disposed in the first vacuum processing region 10, the second deposition source 131 being disposed in the second vacuum processing region 12. In the vacuum processing region, the substrate 106 is supported by the coating drum while being processed. However, it should be understood that more than two deposition sources may be provided according to other embodiments that may be combined with other embodiments described herein. For example, four, five, six, or even more deposition sources may be provided. The vacuum processing zones are separated from adjacent vacuum processing zones and from the main volume of the vacuum chamber 101 by a gas separation unit 120.

In some embodiments, which can be combined with other embodiments described herein, the first vacuum treatment zone 10 is arranged radially outside the coating drum 110 in a first angular position and the second vacuum treatment zone 12 is arranged radially outside the coating drum 110 in a second angular position.

According to some embodiments described herein, the gas separation unit 120 is configured to have a variable position, as indicated by arrow Y. The gas separation unit 120 generally includes a wall 122, the wall 122 preventing gases in one vacuum processing region from entering an adjacent region, such as an adjacent vacuum processing region. Furthermore, the gas separation channel 20 may be at least partially configured as a slit 21 between the coating drum 110 and the slit wall 124.

Similar to the vacuum processing apparatus described above, at least one of the vacuum processing regions includes a gas inlet for introducing a test gasBody 31 (e.g. CO)₂) Is introduced into the vacuum treatment zone. The test gas sensor 50 is associated with the other vacuum processing regions, wherein the test gas sensor 50 is configured to measure a first content of the test gas in the other vacuum processing regions, i.e., a first content of the test gas in the background gas taken from the respective vacuum processing region.

The test gas sensor 50 may be connected to an exhaust line of a vacuum pump configured to exhaust other vacuum processing regions.

Again, gas separation channels 121 are arranged on opposite sides of the respective vacuum processing regions. Specifically, the flexible substrate 106 may enter the vacuum processing region along the first gas separation channel and exit the vacuum processing region along the second gas separation channel, respectively.

Details of the gas flow (particularly the separation gas), the separation gas inlet, details of the gas separation channel and other features are not shown in fig. 3 in order to provide a clear illustration. In this regard, reference may be made to the above-described embodiments.

In some embodiments, each of the two or more vacuum processing zones is provided with a gas inlet for introducing a test gas, and each of the two or more vacuum processing zones includes an associated test gas sensor for measuring the content of the test gas present in the respective vacuum processing zone. Thus, the quality of vacuum separation between any pair of vacuum processing regions can be inspected, and misaligned separation gas channels can be easily located and modified.

FIG. 4 depicts a schematic cross-sectional view of another roll-to-roll deposition system for performing methods in accordance with embodiments described herein. The roll-to-roll deposition system is configured as a vacuum deposition apparatus 500 for depositing thin films on a substrate 106 in a first vacuum processing region 10 and a second vacuum processing region 12.

The vacuum deposition apparatus 500 comprises a vacuum chamber 501, the vacuum chamber 501 having a main volume 503, wherein a first source housing having a first deposition source 510 and a second source housing having a second deposition source 520 are attached to the vacuum chamber 501 in a gastight manner directly or indirectly via a fixing means in such a way that the source housings at least partially protrude into the main volume 503 of the vacuum chamber 501 towards the substrate support. The substrate support is a coating drum 110, said coating drum 110 being rotatable around a drum axis 111. In some embodiments, the main chamber vacuum pump 71 is connected to a pumping outlet arranged for directly evacuating the main volume 503.

The coating drum 110 may be provided with a substrate guiding surface for moving the flexible substrate 106 through the open front side of the source housing containing the continuous deposition source. The source housing of the first deposition source 510 may include a first gas inlet 30 to introduce a process gas or test gas 31 into the first vacuum processing region 10 and an exhaust outlet to remove the process gas or test gas from the first vacuum processing region 10. Similarly, the source housing of the second deposition source 520 may include a second gas inlet to introduce process or test gases into the second vacuum processing region 12 and an exhaust outlet having a vacuum pump 42 connected to the exhaust outlet to remove process or test gases from the second vacuum processing region 12.

The test gas sensor 50 is configured to measure a first amount of the test gas present in the second vacuum processing region 12.

In some embodiments, a pre-treatment plasma source 523 (e.g., an RF plasma source) may be provided to treat the substrate 106 with plasma prior to moving the substrate 106 through the deposition source. Alternatively or additionally, the vacuum deposition apparatus 500 may include a preheating unit 529 to heat the flexible substrate 106. For example, a radiant heater, an electron beam heater, or any other element may be provided to heat the substrate prior to substrate processing.

Gap gates 524 may additionally be provided that are capable of ensuring vacuum separation between portions of the vacuum chamber 501. The substrate 106 may be wound from the first roll 528 and may be transferred to the coating drum 110 over a number of intermediate rolls 525, the substrate 106 being coated on the coating drum 110. The substrate may then be transferred on the other intermediate roller 525 to the second roller 526. Further, intermediate rollers 527 may be provided.

The deposition source may be provided as a CVD deposition source, in particular a hot wire CVD deposition source. The first gas inlet 30 may comprise a showerhead configured to evenly distribute the process gas or the test gas in the first vacuum processing region.

A separation gas channel (not shown) may be provided in the sidewall of the source housing for introducing a separation gas (e.g., an inert gas, such as N) at one or more separation gas inlet locations₂) Is introduced into the gas separation channel 20. In particular, two or more separation gas inlets configured for introducing separation gas into the slots of the gas separation channel 20 may be provided along the gas separation channel. The gas separation channel 20 may further comprise a central section which is open to the main volume 503 of the vacuum chamber 501. The gas separation quality of the gas separation channel 20 can be improved.

Fig. 5 depicts various gas flows in a gas separation channel 20 when performing the methods described herein, the gas separation channel 20 extending between the first vacuum processing region 10 and the second vacuum processing region 12.

A first zone vacuum pump 43 is connected to the first vacuum processing zone 10, a second zone vacuum pump 42 is connected to the second vacuum processing zone 12, and a main chamber vacuum pump 71 is connected to the main volume of the vacuum chamber.

The separation gas 60 may be introduced into the first slit section and into the second slit section of the gas separation channel 20, wherein a central section of the gas separation channel 20 may be open to the main volume 3.

A test gas 31 may be introduced into the first vacuum processing region 10. The content of the test gas present in the second vacuum processing region 12 may be measured via the test gas sensor 50. In some embodiments, a test gas sensor is disposed in the exhaust line of the second zone vacuum pump 42.

Fig. 6 depicts a portion of a roll-to-roll deposition system that may be configured as a hot-wire CVD deposition system. The deposition system includes three, four, or

more deposition sources

510, 520, 530, wherein the source housing includes vacuum processing regions, such as a first vacuum processing region 10 and a second vacuum processing region 12. A coating drum 110 having a substrate supporting surface to support and guide the flexible substrate 106 is provided.

The source housing comprising the vacuum treatment zone is arranged radially outside the coating drum in individual angular positions such that a slit is provided between the front wall of the source housing and the coating drum. The slit is a portion of the gas separation channel 20 between the vacuum processing regions.

According to the method described herein, a test gas 31 is introduced into a first vacuum processing region, and a first content of the test gas in background gas taken from another vacuum processing region is measured. From the measured content, it can be determined whether the gas separation channel should be adjusted. According to some embodiments described herein, a second amount of the test gas in the background gas taken from the first vacuum processing region is measured, and the first amount is compared to the second amount.

The test gas may be CO₂The gas and test gas sensor may be a specific gas sensor, in particular optical CO₂A sensor.

Fig. 7 depicts a flow diagram of a method of inspecting gas separation quality of a gas separation channel according to embodiments described herein.

In block 710, a test gas is introduced into a first vacuum processing region, and in block 720, a first content of the test gas is measured for a background gas in a second vacuum processing region. If the measured content is above a preset threshold, the gas separation quality may be insufficient and the gas separation channel may be adjusted.

In block 810, a gas separation quality of a gas separation channel disposed between a first vacuum processing region and a second vacuum processing region is examined. In block 811, a test gas is introduced into the first vacuum processing region, and in block 812, a first amount of the test gas in a background gas in the second vacuum processing region is measured. For example, the first content of the test gas is measured in the background gas pumped from the second vacuum processing region, wherein the gas sensor may be arranged in an exhaust line of the vacuum pump.

Introducing the test gas into the first vacuum processing region may include providing a continuous flow of the test gas (particularly at a fixed test gas flow rate) into the first vacuum processing region. The test gas flow rate may be similar to or may correspond to a typical process gas flow rate used to deposit a film on a substrate.

In block 820, the gas separation channel is adjusted based on the measured content of the test gas. For example, the gas separation channel may be adjusted by adjusting the width of the slit of the gas separation channel, by modifying the separation gas flow rate, by modifying the pumping rate, and/or by adjusting the cooling or heating temperature of the substrate support and/or the deposition source.

At block 830, the substrate is directed from the first vacuum processing region to the second vacuum processing region along the gas separation channel while depositing a first material film on the substrate in the first vacuum processing region and a second material film on the substrate in the second vacuum processing region. Depositing the first material film may include introducing a first CVD process gas into the first vacuum processing region, and depositing the second material film may include introducing a second CVD process gas into the second vacuum processing region.

In view of the above, while the foregoing is directed to embodiments of the present 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.

Claims

1. A method of inspecting gas separation quality of a gas separation channel (20) extending between a first vacuum processing region (10) and at least one second vacuum processing region (12) in a vacuum chamber (2), wherein the gas separation channel (20) is configured as a passage for substrates while reducing gas flow from the first vacuum processing region (10) into the at least one second vacuum processing region (12), the method comprising:

introducing a test gas (31) into the first vacuum processing zone (10), wherein the test gas is CO₂A gas;

measuring a first content (33) of the test gas in a background gas (32) in the at least one second vacuum processing region (12), the first content (33) being measured via an optical, spectroscopic or chemical gas sensor configured for measuring the test gas, wherein the gas sensor is CO₂A sensor;

measuring a second content (34) of the test gas in a second background gas (35) in the first vacuum processing region (10); and

comparing the first content (33) of the test gas with the second content (34) of the test gas.

2. The method of claim 1, wherein molecules of the test gas have a molecular mass of 5g/mol or more and 500g/mol or less.

3. The method of claim 1, further comprising:

introducing a separation gas (60) into the gas separation channel (20) between the first vacuum treatment zone (10) and the at least one second vacuum treatment zone (12), wherein a first main flow direction of the separation gas (60) in at least a portion of the gas separation channel (20) is opposite to a second main flow direction of the test gas.

4. The method according to claim 1, wherein the gas separation channel (20) is open to a main volume (3) of the vacuum chamber (2) in a section between the first vacuum treatment zone (10) and the at least one second vacuum treatment zone (12), the method further comprising:

vacuum pumping is performed from a main pumping outlet (70) connected to the main volume (3).

5. Method according to claim 1, wherein a first pressure in at least one of the first vacuum treatment zone (10) and the at least one second vacuum treatment zone (12) is maintained in a range between 0.1mbar and 2 mbar.

6. The method according to claim 5, wherein the first pressure is maintained at a higher level than a second pressure in a main volume (3) of the vacuum chamber.

7. A vacuum processing apparatus (1) for processing a substrate, comprising:

a vacuum chamber (2);

a first vacuum processing zone (10), at least one second vacuum processing zone (12), and a gas separation channel (20) extending between the first vacuum processing zone (10) and the at least one second vacuum processing zone (12), wherein the gas separation channel (20) is configured for passage of the substrate while reducing gas flow from the first vacuum processing zone (10) into the at least one second vacuum processing zone (12);

a first gas inlet (30) for introducing a test gas (31) into the first vacuum processing zone (10);

a first test gas sensor (50) configured for measuring a first content (33) of the test gas in a background gas (32) in the at least one second vacuum processing region (12), wherein the first test gas sensor is an optical, spectroscopic or chemical gas sensor configured to measure the test gas, wherein the first test gas sensor is CO₂A sensor; and

a second test gas sensor (51) configured for measuring a second content (34) of the test gas in a second background gas (35) in the first vacuum processing region (10).

8. Vacuum processing apparatus according to claim 7, wherein the first test gas sensor (50) is arranged in an exhaust line (41) of a vacuum pump (42) or adjacent to the exhaust line (41) of the vacuum pump (42), the exhaust line (41) being connected to the at least one second vacuum processing region (12).

9. Vacuum processing apparatus according to claim 7 or 8, wherein the gas separation channel (20) is at least partly configured as a slit (21), the slit (21) being located between a gas separation wall (22) and a substrate support (80), the substrate support (80) being configured to support the substrate.

10. Vacuum processing apparatus according to claim 9, wherein the substrate support (80) is a coating drum (110), the coating drum (110) being configured to rotate around a drum axis (111), wherein the first vacuum processing region (10) is arranged radially outside the coating drum (110) at a first angular position and the at least one second vacuum processing region (12) is arranged radially outside the coating drum at a second angular position.

11. The vacuum processing apparatus according to claim 7 or 8, further comprising one, two, or more separation gas inlets (61), the separation gas inlets (61) being configured for introducing separation gas into the separation gas channel (20).

12. Vacuum processing apparatus according to claim 7 or 8, wherein the gas separation channel (20) comprises a first slit separating the first vacuum processing zone (10) from a main volume (3) of the vacuum chamber (2), a central section (25) being open to the main volume (3) of the vacuum chamber (2), and a second slit separating the main volume (3) from the at least one second vacuum processing zone (12), wherein a main pumping outlet (70) is provided for pumping the main volume (3) of the vacuum chamber (2).

13. A vacuum deposition apparatus (100) for depositing a film on a substrate (106), comprising:

a vacuum chamber (2), a first vacuum treatment zone (10) and at least one second vacuum treatment zone (12) being arranged in the vacuum chamber (2);

a first deposition source (130, 510) and a second deposition source (131, 520), the first deposition source (130, 510) being disposed in the first vacuum processing region (10) and configured for depositing a thin layer of a first material on the substrate (106), the second deposition source (131, 520) being disposed in the at least one second vacuum processing region (12) and configured for depositing a thin layer of a second material on the substrate (106);

a substrate support (80), the substrate support (80) having a substrate supporting surface for guiding the substrate along a gas separation channel (20) from the first vacuum processing zone (10) to the at least one second vacuum processing zone (12) or vice versa;