JP6411675B2 - Method for measuring deposition rate and deposition rate control system - Google Patents

Description

  The present disclosure relates to a method for controlling the deposition rate of evaporation material, a deposition rate control system, and an evaporation source for material evaporation. The present disclosure particularly relates to a method and control system for controlling the deposition rate of evaporated organic material.

  An organic evaporator is a tool for the manufacture of organic light emitting diodes (OLEDs). An OLED is a special light emitting diode that includes a thin film of an organic compound with a light emitting layer therein. Organic light emitting diodes (OLEDs) are used in the manufacture of television screens, computer monitors, cell phones, and other portable devices for displaying information. OLEDs can also be used for general space illumination. The range of colors, brightness, and viewing angles possible with OLED displays is larger than that of conventional LCD displays because OLED pixels emit directly and do not include a backlight. Thus, the energy consumption of an OLED display is significantly less than that of a conventional LCD display. Furthermore, in fact, OLEDs can be manufactured on flexible substrates, resulting in further applications.

  The functionality of the OLED depends on the coating thickness of the organic material. This thickness must be within a predetermined range. Therefore, in the manufacture of OLEDs, the deposition rate at which the coating with organic material is affected is controlled to be within a predetermined tolerance. In other words, the deposition rate of the organic evaporator must be completely controlled in the manufacturing process.

  Therefore, not only for OLED applications, but also for other evaporation processes, a high deposition rate is required over a relatively long time. There are multiple measurement systems for measuring the deposition rate of available evaporators. However, these measurement systems suffer either insufficient accuracy and / or insufficient stability over the desired period.

  Accordingly, there is a continuing need for providing improved deposition rate measurement methods, deposition rate control systems, evaporators and deposition equipment.

  In view of the above, a method, a deposition rate control system, an evaporation source, and a deposition apparatus for measuring the deposition rate of an evaporating material according to the independent claims are provided. Further advantages, features, aspects and details are apparent from the dependent claims, the description and the drawings.

  According to one aspect of the present disclosure, a method for measuring the deposition rate of an evaporating material is provided. The method includes measuring the deposition rate at a time interval between the first measurement and the second measurement, and adjusting the time interval depending on the measured deposition rate.

  According to another aspect of the present disclosure, a deposition rate control system is provided. The deposition rate control system includes a deposition rate measurement assembly for measuring the deposition rate of the evaporating material, a controller coupled to the deposition rate measurement assembly, and an evaporation source, wherein the controller sends a control signal to the deposition rate measurement assembly. Configured to provide. In particular, the controller is configured to execute program code, which when executed executes a method for measuring a deposition rate of evaporative material according to embodiments described herein.

  According to a further aspect of the present disclosure, an evaporation source for material evaporation is provided. The evaporation source has an evaporation crucible configured to evaporate the material and a distribution pipe having one or more outlets provided along the length of the distribution pipe for supplying the evaporation material to the substrate at a deposition rate And including a distribution pipe in fluid communication with the evaporating crucible and a deposition rate control system according to embodiments described herein.

  According to yet another aspect of the present disclosure, a deposition apparatus is provided for applying material to a substrate in a vacuum chamber at a deposition rate. The deposition apparatus includes at least one evaporation source according to embodiments described herein.

  The present disclosure is also directed to an apparatus for performing the disclosed method including an apparatus portion for performing the method. The method may be performed by hardware components, a computer programmed by appropriate software, any combination of the two, or any other method. Furthermore, the present disclosure is also directed to operation of the described apparatus. This includes methods for performing all functions of the device.

  In order that the above features of the present disclosure as set forth herein may be more fully understood, a more specific description of the present disclosure that has been briefly outlined above may be obtained by reference to the embodiments. . The accompanying drawings relate to embodiments of the disclosure and are described below.

FIG. 4 shows a block diagram illustrating a method for measuring the deposition rate of an evaporating material according to embodiments described herein. FIG. 2 shows a schematic diagram of a deposition rate control system according to embodiments described herein. FIG. 2 shows a schematic diagram of a deposition rate control system according to embodiments described herein. FIG. 2 shows a schematic diagram of a deposition rate control system according to embodiments described herein. FIG. 3 shows a schematic diagram for measuring deposition rate according to an embodiment of a method for measuring deposition rate as described herein. A and B each show a block diagram illustrating an embodiment of a method for measuring the deposition rate of the evaporative material described herein. A shows a schematic view of a measurement assembly in a first state according to embodiments described herein, and B shows a schematic side view of a measurement assembly in a second state according to embodiments described herein. . A and B show schematic side views of an evaporation source according to embodiments described herein. FIG. 3 shows a schematic top view of a deposition apparatus for applying material to a substrate in a vacuum chamber according to embodiments described herein.

  Reference will now be made in detail to various embodiments of the disclosure, one or more examples of which are illustrated. Within the following description of the drawings, the same reference numbers refer to the same components. In the following, only the differences with respect to the individual embodiments are described. Each example is provided by way of explanation of the disclosure, but is not intended to limit the disclosure. Furthermore, features illustrated and described as part of one embodiment may be used in or combined with other embodiments to yield still another embodiment. Good. The description is intended to include such modifications and alterations.

  In this disclosure, the expression “oscillating quartz for measuring deposition rate” is used to measure the change in the mass of the deposited material on the oscillating quartz per unit area by measuring the change in frequency of the oscillating quartz resonator. Can be understood as an oscillation crystal. In particular, in this disclosure, an oscillating crystal can be understood as a quartz crystal resonator. More specifically, “oscillating quartz for measuring deposition rate” can be understood as quartz quartz microbalance (QCM).

  In this disclosure, the expression “deposition rate accuracy” relates to the deviation of the actual deposition rate from a preselected target deposition rate, eg, the measured deposition rate. For example, the smaller the deviation of the actual deposition rate measured from the preselected target deposition rate, the higher the accuracy of the deposition rate.

  Referring to FIG. 1, a method 100 for measuring a deposition rate of evaporative material according to embodiments described herein measures a deposition rate at a time interval ΔT between a first measurement and a second measurement. 110 and adjusting 120 the time interval depending on the measured deposition rate. In particular, the measured deposition rate dependence may be a function of the deposition rate. For example, the first measurement and / or the second measurement may be performed in 5 minutes or less, in particular 3 minutes or less, more specifically 1 minute or less. According to embodiments that can be combined with other embodiments described herein, the time interval ΔT between the first measurement and the second measurement is 50 minutes or less, in particular 35 minutes or less, more specifically Specifically, it can be adjusted to 20 minutes or less. Thus, adjusting the time interval between two measurements depending on the function of the deposition rate may increase the accuracy of the deposition rate measurement. In particular, by adjusting the time interval between two measurements depending on the function of the deposition rate, the lifetime of the deposition measurement device may be extended. In particular, the exposure of the measuring device to the evaporating material for measuring the deposition rate of the evaporating material is reduced to a minimum, which can be beneficial for the entire life of the measuring device.

  According to embodiments that can be combined with other embodiments described herein, the time interval between the first measurement and the second measurement during the initial adjustment of the preselected target deposition rate. ΔT may be shorter compared to the time interval ΔT between the first measurement and the second measurement when a preselected target deposition rate is reached. For example, during the initial adjustment of the preselected target deposition rate, the time interval ΔT between the first measurement and the second measurement is 10 minutes or less, in particular 5 minutes or less, more specifically 3 minutes. It can be: When the preselected target deposition rate is reached, the time interval ΔT between the first measurement and the second measurement is a lower limit of 10 minutes, in particular a lower limit of 20 minutes, more specifically a lower limit of 30 minutes. And an upper limit of 35 minutes, in particular, an upper limit of 45 minutes, more specifically, an upper limit of 50 minutes. In particular, when a preselected target deposition rate is reached, the time interval ΔT between the first measurement and the second measurement may be 40 minutes.

  According to embodiments that can be combined with other embodiments described herein, the function of the measured deposition rate is the slope of the deposition rate, a Boolean determination of the deposition rate within a predetermined range, measured Selected from the group consisting of a polynomial function of the difference of the deposition rate to a nominal / set value for a given deposition rate, and an oscillation function of the measured deposition rate. Therefore, adjusting the time interval ΔT between two measurements based on a function of the deposition rate may increase the accuracy of the deposition rate measurement. Furthermore, the exposure of the measuring device to the evaporating material for measuring the deposition rate of the evaporating material is reduced to a minimum, which can be beneficial for the entire lifetime of the measuring device.

  According to embodiments that can be combined with other embodiments described herein, the time interval between the first measurement and the second measurement is a deposition rate from a preselected slope of the deposition rate. May be adjusted depending on the measured deviation of the slope. In particular, the first measurement and the second measurement when a preselected slope of a deposition rate of less than 5%, in particular less than 3%, more specifically less than 1.5%, for example 1% or less, is detected. The time interval between can be increased. In particular, if a deviation of the measured slope is detected from a preselected slope of a deposition rate of 5%, in particular about 3%, more specifically more than 1%, for example 1.5%, the first The time interval between the measurement and the second measurement can be reduced.

  According to embodiments that can be combined with other embodiments described herein, the time interval between the first measurement and the second measurement can be adjusted based on a Boolean decision. For example, if the deviation of the measured deposition rate from the preselected target deposition rate exceeds a preselected upper deposition rate or falls below a preselected lower deposition rate, the first measurement and the first The time interval between the two measurements can be reduced. For example, the preselected upper limit deposition rate can be + 3% or less, particularly + 2% or less, more specifically + 1% or less of the target deposition rate 190. In particular, the preselected upper deposition rate can be 1.5%. The lower limit deposition rate is −3% or less (for example, −2.5%) of the target deposition rate 190, particularly −2% or less (for example, −1.5%), more specifically, −1% or less (for example, 0.75%). In particular, the preselected lower limit deposition rate can be -1.5%.

  According to embodiments that can be combined with other embodiments described herein, the time interval between the first measurement and the second measurement is a preselected deposition rate of the measured deposition rate. Can be adjusted based on a polynomial function of the difference to the nominal / set value of. For example, a polynomial function that is a function of the deposition rate measured from a preselected target deposition rate that is less than 5%, in particular less than 3% (eg less than 1.5%), more specifically less than 1%. If a deviation is detected, the time interval between the first measurement and the second measurement may increase. Thus, a deviation of the polynomial function from the preselected target deposition rate to a measured deposition rate of more than 5%, in particular about 3%, more specifically 1% (eg, 1.5% or more) is detected. The time interval between the first measurement and the second measurement may be reduced.

  According to embodiments that can be combined with other embodiments described herein, the time interval between the first measurement and the second measurement is adjusted based on an oscillation function of the measured deposition rate. obtain. For example, the deviation of the oscillation function relative to the measured deposition rate is detected from a pre-selected target deposition rate that is less than 5%, in particular less than 3% (eg 1.5% or less), more specifically less than 1%. If done, the time interval between the first measurement and the second measurement may be increased. Thus, a deviation of the oscillating function from the preselected target deposition rate to a measured deposition rate of more than 5%, in particular about 3%, more specifically 1% (eg 1.5% or more) is detected. The time interval between the first measurement and the second measurement may be reduced.

  FIG. 2 shows a schematic diagram of a deposition rate control system 200 according to embodiments described herein. The deposition rate control system 200 includes a deposition rate measurement assembly 210 for measuring the deposition rate of the evaporation material, and a controller 220 coupled to the deposition rate measurement assembly 210 and the evaporation source 300. According to the embodiments described herein, the controller 220 may be configured to provide a control signal to the deposition rate measurement assembly 210. In particular, the controller 220 is configured to execute program code, which when executed executes a method for measuring a deposition rate according to embodiments described herein.

  For example, the control signal provided from the controller 220 to the deposition rate measurement assembly 210 may be for adjusting the time interval between the first and second measurements of the deposition rate. In particular, depending on the measured deposition rate, the time interval between the first measurement and the second measurement can be increased or decreased. For example, if the measured deposition rate is determined to meet a preselected criterion, eg, a stability criterion, the time interval between the first measurement and the second measurement may increase. . Thus, if the measured deposition rate is determined not to meet a preselected criterion, for example, a stability criterion, the time interval between the first measurement and the second measurement is increased. obtain.

  Referring to FIG. 2, according to an embodiment that can be combined with other embodiments described herein, the deposition rate measurement assembly 210 can measure the actual deposition rate 199. The measured actual deposition rate 199 data is transmitted from the deposition rate measurement assembly 210 to the controller 220. Depending on the measured actual deposition rate 199, the controller 220 heats a first control signal 125 that controls the evaporation source 300 to adjust the deposition rate, eg, a heating element provided to the deposition source. A signal for cooling and / or a signal for cooling the cooling element supplied to the deposition source, etc. may be provided. According to embodiments that can be combined with other embodiments described herein, the controller 200 may include a closed loop control that includes at least one proportional-integral-derivative (PID) controller for controlling the deposition rate. Further, depending on the measured actual deposition rate 199, the controller 220 may be between two measurements, for example, between a first measurement M1 and a second measurement M2, as shown in FIG. A second control signal 121 may be provided to the deposition rate measurement assembly 210 for adjusting the time interval ΔT. Accordingly, by providing a deposition rate control system that includes a controller configured to provide a control signal to the deposition rate measurement assembly, the exposure of the measurement device to measure the deposition rate of the evaporation material is reduced to the evaporation material. , Can be reduced to a minimum value. This can be beneficial for the entire life of the measuring device.

  As shown in FIG. 3, according to an embodiment that can be combined with other embodiments described herein, a pre-selected value dm / dt for the deposition rate is provided to the deposition rate control system 200. May be defined for In particular, the target deposition rate 190, the upper limit deposition rate 191 and the lower limit deposition rate 192 may be selected. For example, the measured actual deposition rate 199 is determined to meet a selected deposition rate accuracy criterion when it is in the range of an upper limit deposition rate 191 and a lower limit deposition rate 192, as shown in FIG. Also good. According to embodiments that can be combined with other embodiments described herein, the upper deposition rate 191 is not more than + 3% of the target deposition rate 190, particularly not more than + 2% of the target deposition rate 190 (eg, 1.. 5% or less), more specifically + 1% or less of the target deposition rate 190. The lower limit deposition rate 192 is −3% or less (eg −2.5%) of the target deposition rate 190, in particular −2% or less (eg −1.5%) of the target deposition rate 190, more specifically It can be −1% or less (eg, −0.75%) of the target deposition rate 190.

  Referring to FIG. 4, according to an embodiment that can be combined with other embodiments described herein, a control signal provided by the controller 220 to the deposition rate measurement assembly 210, eg, a second control signal 121. May be for adjusting the time interval ΔT between the first measurement M1 and the second measurement M2 of the deposition rate. As shown in FIG. 4, the first measurement M1 may be performed in a first period. The actual deposition rate 199 deposition rate measurement data may be transmitted from the deposition rate measurement assembly 210 to the controller 220. Depending on the measured actual deposition rate 199 in the first measurement M1, the time interval ΔT between the first measurement M1 and the subsequent measurement, for example the second measurement M2, can be determined. For example, if the measured deposition rate is determined to meet the selected deposition rate accuracy criteria, the time interval ΔT between the first measurement M1 and the subsequent measurement, eg, the second measurement M2, is increased. Can do. For example, the time interval ΔT between the first measurement M1 and the subsequent measurement can be increased compared to a preset value of the time interval between two measurements, in particular between two subsequent measurements.

  Thus, according to embodiments that can be combined with other embodiments described herein, the time interval between the second measurement M2 and the subsequent measurement, eg, the third measurement, is the second measurement. It can be determined depending on the measured actual deposition rate 199 of M2. For example, if it is determined that the measured deposition rate of the second measurement M2 is more accurate than the measured deposition rate of the first measurement M1, the time interval between the second measurement M2 and the subsequent measurement Can increase. Conversely, if the measured deposition rate of the second measurement M2 is determined to be less accurate than the measured deposition rate of the first measurement M1, the time between the second measurement M2 and the subsequent measurement The interval can be reduced.

  In FIG. 5, an exemplary schematic for measuring deposition rate using a method for measuring deposition rate according to embodiments described herein is shown. In particular, in FIG. 5, an exemplary actual deposition rate 199 [dm / dt] is depicted over time t. Further, FIG. 5 shows an exemplary target deposition rate 190, an exemplary upper limit deposition rate 191, and an exemplary lower limit deposition rate 192. As exemplarily shown in FIG. 5, an exemplary actual deposition rate 199 may vary over time t. In the ideal case, the actual deposition rate 199 is constant over time and corresponds to a preselected target deposition rate 190. However, in practice, the actual deposition rate 199 may oscillate around a preselected target deposition rate 190, as exemplarily shown in FIG. Thus, the time interval between the first measurement and the second measurement can be adjusted depending on the measured deposition rate.

  For example, the measured deposition rate is characterized with respect to a preselected criterion, eg, a stability criterion, and the time interval between a measurement that the preselected criterion must be evaluated and the subsequent measurement is evaluated Can be adjusted depending on the results. For example, if the actual deposition rate 199 of a measured measurement is assessed to be more accurate than the previous measurement, the time interval over which subsequent measurements are performed may increase. In particular, as exemplarily shown in FIG. 5, the measured deposition rate of the second measurement M2 is determined to be more accurate compared to the first measurement M1, so that the subsequent third measurement is The second time interval ΔT2 is increased compared to the first time interval ΔT1. Thus, as exemplarily shown in FIG. 5, if the actual deposition rate 199 of the measured measurement is evaluated to be less accurate than the previous measurement, the time interval over which the subsequent measurement is performed decreases. obtain. In particular, as exemplarily shown in FIG. 5, the measured deposition rate of the fourth measurement M4 is determined to be less accurate compared to the third measurement M3, so that the subsequent fifth measurement M5 is , Implemented with a fourth time interval ΔT4 which is reduced compared to the third time interval ΔT3.

  According to an embodiment of the method 100 for measuring the deposition rate of the evaporative material that can be combined with other embodiments described herein, the method 100 is exemplarily shown in the block diagram of FIG. 6A. And shielding 130 the deposition rate measuring device from the vaporized material between the first measurement and the second measurement. For example, the shielding 130 may be a shutter between the deposition rate measurement device 211 and the measurement outlet 230 for supplying evaporation material to the evaporation rate measurement device 211, as exemplarily shown in FIGS. 7A and 7B. 213 may be moved. Thus, the deposition rate measuring device is protected from the evaporated material between measurements, which can be beneficial for the entire lifetime of the deposition rate measuring device.

  According to an embodiment of the method 100 for measuring the deposition rate of the evaporating material that can be combined with other embodiments described herein, the method 100 is between a first measurement and a second measurement. Cleaning 140 a deposition material deposition rate measuring device 211. Among other things, cleaning 140 may include evaporating material deposited on the deposition rate measuring device 211. For example, evaporating material deposited on the deposition rate measuring device 211 can be performed by heating the deposition rate measuring device. Thus, by cleaning the deposition rate measuring device during the measurement, the entire lifetime of the deposition rate measuring device can be extended.

  7A and 7B, schematic views of a measurement assembly of a deposition rate control system according to embodiments described herein are shown. In particular, a deposition rate measurement assembly 210 for measuring the deposition rate of an evaporating material according to embodiments described herein may include a deposition rate measurement device 211 that includes an oscillating crystal 212 for measuring the deposition rate. 7A and 7B, the deposition rate measurement device 211 can include a holder 250 in which the oscillating crystal 212 is disposed. The holder 250 includes a measurement hole 122 that can be configured and arranged so that the evaporating material is deposited on the oscillating crystal 212 to measure the deposition rate of the evaporating material.

  In accordance with an embodiment that can be combined with other embodiments described herein, the deposition rate measurement assembly 210 includes a measurement outlet for supplying vaporized material to the deposition rate measurement device 211, in particular to the oscillation crystal 212. A shutter 230 may be included to block the evaporation material supplied from 230. Referring to FIGS. 7A and 7B, the shutter 213 is configured to be movable from the first state of the shutter to the second state of the shutter, for example, to be linearly movable. That is, the shutter is configured as a movable shutter. can do. Alternatively, the shutter may be configured to be pivotable from the first state to the second state. For example, the first state of the shutter may be an open state where the shutter 213 does not block the measurement outlet 230 to provide evaporative material to the oscillating crystal 212, as exemplarily shown in FIG. 7A. Thus, the second state of the shutter 213 is that the shutter 213 blocks the measurement outlet 230, so that the oscillating crystal 212 is out of the vaporized material supplied through the measurement outlet 230, as exemplarily shown in FIG. 7B. It can be in a protected state.

  By providing a shutter in the measurement assembly, the measurement device, in particular the oscillating crystal, is protected from the vaporized material during the deposition rate measurement and can be beneficial for the entire lifetime of the deposition rate measurement device. Furthermore, by using a shutter to shield the deposition rate measuring device from the vaporized material between the first measurement and the second measurement, the negative effect of the heat supplied by the vaporized material on the measurement device is reduced. Or even excluded. For example, the quality, accuracy, and stability of the deposition rate measurement can be increased by shielding the deposition rate measurement device with a shutter according to embodiments described herein.

  Referring to FIG. 7B, according to an embodiment that can be combined with other embodiments described herein, the shutter 213 can include a thermal protection shield 216 to protect the oscillating crystal 212 from evaporating material. As exemplarily shown in FIG. 7B, the heat protection shield 216 may be disposed on the side of the shutter 213 facing the measurement outlet 230. In particular, the heat protection shield 216 may be configured to reflect the thermal energy supplied by the evaporating material supplied through the measurement outlet 230. According to embodiments that can be combined with other embodiments described herein, the heat protection shield 216 can be a plate, eg, sheet metal. Alternatively, the heat protection shield 216 may include two or more plates, such as sheet metal, spaced from each other, for example by a gap of 0.1 mm or more. For example, the sheet metal may have a thickness of 0.1 mm to 3.0 mm. In particular, the heat protection shield is a group consisting of ferrous or non-ferrous materials, such as copper (Cu), aluminum (Al), copper alloys, aluminum alloys, brass, iron, titanium (Ti), ceramics and other suitable materials. At least one selected from.

  Thus, a measurement assembly that includes a heat protection shield according to embodiments described herein may be beneficial to protect the oscillating crystal from the temperature of the evaporating material, eg, heat, especially when the shutter is in a closed state. In particular, the deposition rate measuring device can be cooled when shielded from the evaporated material between the two measurements. Thus, the overall lifetime of the deposition rate measuring device can be extended.

  According to embodiments that can be combined with other embodiments described herein, the deposition rate measurement assembly 210 is deposited on a deposition rate measurement device 211 as exemplarily shown in FIGS. 7A and 7B. It may include at least one heating element 214 for heating the deposition rate measuring device 211 to a temperature at which the deposited material evaporates. In particular, the heating element 214 may be disposed in the holder 250, for example, adjacent to or in proximity to the oscillating crystal 212. The heating element 124 may be configured to heat the oscillating crystal and / or the holder. Thus, the deposition rate measuring device can be cleaned in situ between the two measurements. This can be beneficial to the overall lifetime of the deposition rate measurement device and the achievable measurement accuracy.

  According to embodiments that can be combined with other embodiments described herein, the deposition rate measurement assembly 210 can include a heat exchanger 232. In particular, the heat exchanger may be disposed in the holder, for example, adjacent or close to the oscillating crystal and / or adjacent or close to the heating element 214. The heat exchanger 232 may be configured to exchange heat with the oscillating crystal and / or the holder 120 and / or the heating element 214. For example, a heat exchanger may include a tube through which cooling fluid is supplied. The cooling fluid can be a liquid such as water or a gas such as air. In addition or alternatively, the heat exchanger may include one or more Peltier elements. Thus, by providing a heat exchanger 232 in the measurement assembly, the negative effects of high temperatures on the deposition rate measurement quality, accuracy and stability can be reduced or even eliminated. In particular, providing a heat exchanger in the measurement assembly can be used after the measurement device has been cleaned by heating, for example, to evaporate the deposited material from the deposition rate measurement device, between the first measurement and the second measurement. It can be beneficial to cool the measuring device.

  Referring to FIG. 7B, according to an embodiment that can be combined with other embodiments described herein, the deposition rate measurement assembly 210 can be used to determine the temperature of the deposition rate measurement device 211, particularly the oscillation crystal 212 and / or holder. A temperature sensor for measuring 250 temperatures may be included. By providing a temperature sensor 217 in the deposition rate measurement assembly 210, information about the temperature of the measurement assembly can be obtained, and a critical temperature can be detected such that the oscillating crystal is measured incorrectly. Thus, when the critical temperature of the deposition rate detection device 211 is detected by a temperature sensor, an appropriate reaction can be initiated, for example, cooling by using a heat exchanger is initiated.

  According to embodiments that can be combined with other embodiments described herein, the deposition rate measurement assembly 210 includes a temperature control system for controlling the temperature of the oscillating crystal 212 and / or the temperature of the holder 250. obtain. Among other things, the temperature control system may include one or more temperature sensors 217, a heat exchanger 232, a heating element 214 and a sensor controller 233. As exemplarily shown in FIG. 7B, the sensor controller 233 can be coupled to the temperature sensor 217 to receive data measured by the temperature sensor 217. Further, the sensor controller 233 can be coupled to the heat exchanger 232 to control the temperature of the holder 250 and / or the oscillating crystal 212. Further, the sensor controller 233 may be coupled to the heating element 214 to control the heating temperature of the holder 250 and / or the oscillating crystal 212, for example during the aforementioned cleaning.

  8A and B show schematic side views of an evaporation source 300 according to embodiments described herein. According to an embodiment, the evaporation source 300 includes an evaporation crucible 310 configured to evaporate a material, for example an organic material. In addition, the evaporation source 300 includes a distribution line 320 having one or more outlets 322 provided along the length of the distribution line for providing evaporation material, as typically shown in FIG. 8B. According to an embodiment, the distribution pipe 320 is in fluid communication with the evaporating crucible 310, for example, via a steam conduit 322, as shown typically in FIG. 8B. The steam conduit 322 can be provided to the distribution pipe 320 at the central portion of the distribution pipe or at another position between the lower end of the distribution pipe and the upper end of the distribution pipe. Further, the evaporation source 300 according to the embodiments described herein includes a deposition rate measurement assembly 210 according to the embodiments described herein. As illustrated by way of example in FIGS. 8A and 8B, according to an embodiment that can be combined with other embodiments described herein, the evaporation source 300 includes a deposition rate measurement assembly 210 and an evaporation source 300. A combined controller 220 may be included. As described herein, the controller 220 may provide a first control signal 125 to the evaporation source 300 to adjust the deposition rate. In addition, the controller may provide a second control signal 121 to the deposition rate measurement assembly 210 to adjust the time interval ΔT between the two measurements. Therefore, an evaporation source 300 is provided so that the deposition rate can be measured and controlled with high accuracy.

  As illustrated in FIG. 8A, according to an embodiment that can be combined with other embodiments described herein, the distribution tube 320 can be an elongated tube that includes a heating element 315. The evaporation crucible 130 can be a reservoir for evaporating a material, for example, an organic material, with the heating unit 325. For example, the heating unit 325 can be provided in the housing of the evaporation crucible 310. According to embodiments that can be combined with other embodiments described herein, the distribution tube 320 may provide a source. For example, as illustrated in FIG. 8B, a plurality of outlets 322, such as nozzles, can be disposed along at least one line. According to alternative embodiments (not shown), one elongated hole such as a slit extending along at least one line may be provided. According to some embodiments that can be combined with other embodiments described herein, the source can extend essentially vertically.

  According to some embodiments that can be combined with other embodiments described herein, the length of the distribution tube 320 can correspond to the height of the substrate on which the material is deposited in the deposition apparatus. Alternatively, the length of the distribution pipe 320 may be longer than the height of the substrate on which the material is deposited, for example at least 10% or 20% longer. This can provide uniform deposition at the top and / or bottom of the substrate. For example, the length of the distribution pipe 320 can be set to 1.3 m or more, for example, 2.5 m or more.

  According to embodiments that can be combined with other embodiments described herein, an evaporation crucible 310 can be provided at the lower end of the distribution pipe 320, as exemplarily shown in FIG. 8A. For example, a material such as an organic material can be evaporated in the evaporation crucible 310. The evaporating material may enter the distribution pipe at the bottom of the distribution pipe 320 and be guided essentially laterally through a plurality of outlets 322 of the distribution pipe 320, for example, toward an essentially vertical substrate. With reference to FIG. 8B, a deposition rate measurement assembly 210 according to embodiments described herein may be provided at the upper portion of distribution pipe 320, for example, at the upper end of distribution pipe 320.

  As illustrated by way of example in FIG. 8B, according to an embodiment that can be combined with other embodiments described herein, the measurement outlet 230 is located on the wall of the distribution pipe 320, eg, the back side 224A of the distribution pipe. It can be provided on the wall. Alternatively, the measurement outlet 230 may be provided in the upper wall 224C of the distribution pipe 320. As illustrated by the arrow 231 in FIG. 8B, evaporative material may be provided from the inside of the distribution pipe 320 through the measurement outlet 230 to the deposition rate measurement assembly 210. According to embodiments that can be combined with other embodiments described herein, the measurement outlet 230 may have a hole with a diameter of 0.5 mm to 4 mm. The measurement outlet 230 may include a nozzle. For example, the nozzle may include adjustable holes for adjusting the flow of evaporative material provided to the deposition rate measurement assembly 210. In particular, the nozzle is a lower limit of 1/70 of the total flow provided by the evaporation source, in particular a lower limit of 1/60 of the total flow provided by the evaporation source, more specifically the total flow provided by the evaporation source. From a lower limit of 1/50, an upper limit of 1/40 of the total flow provided by the evaporation source, in particular an upper limit of 1/30 of the total flow provided by the evaporation source, more specifically the total provided by the evaporation source. It may be configured to provide a measured flow rate selected from a range up to an upper limit of 1/25 of the flow rate. For example, the nozzle may be configured to provide a measured flow rate that is 1/54 of the total flow rate provided by the evaporation source.

  FIG. 9 shows a schematic top view of a deposition apparatus 400 for applying material to a substrate 444 in a vacuum chamber 410 according to embodiments described herein. According to embodiments that can be combined with other embodiments described herein, the evaporation source 300 can be provided in a vacuum chamber 410 on a track, such as a linear guide 420 or a looped track. The trajectory of the linear guide 420 may be configured for translational movement of the evaporation source 300. Thus, according to embodiments that can be combined with other embodiments described herein, a driver for translation is provided to the evaporation source 300 in a trajectory and / or linear guide 420 in the vacuum chamber 410. can do. A first valve 405, such as a gate valve, may be provided that allows a vacuum seal to an adjacent vacuum chamber (not shown in FIG. 9). The first valve can be opened for transfer of the substrate 444 or mask 432 into or out of the vacuum chamber 410.

  According to some embodiments that can be combined with other embodiments described herein, additional vacuum chambers, such as maintenance vacuum chamber 411, can be used as shown in FIG. May be provided adjacent to. Accordingly, the vacuum chamber 410 and the maintenance vacuum chamber 411 can be coupled to the second valve 407. The second valve 407 can be configured to open and close the vacuum seal between the vacuum chamber 410 and the maintenance vacuum chamber 411. The evaporation source 300 can be transferred to the maintenance vacuum chamber 411 while the second valve 407 is open. Thereafter, the second valve 407 can be closed to provide a vacuum seal between the vacuum chamber 410 and the maintenance vacuum chamber 411. When the second valve 407 is closed, the maintenance vacuum chamber 411 can be ventilated and opened for evaporation source 300 maintenance without breaking the vacuum in the vacuum chamber 410.

  As typically shown in FIG. 9, the two substrates can be supported on respective transport tracks in the vacuum chamber 410. In addition, two trajectories can be provided on it to provide a mask. Thus, during coating, the substrate 444 can be masked by the respective mask. For example, a mask can be provided on the mask frame 431 to hold the mask 432 in place.

  According to some embodiments that can be combined with other embodiments described herein, the substrate 444 can be supported by a substrate support 426 that can be coupled to the alignment unit 412. The alignment unit 412 can adjust the position of the substrate 444 relative to the mask 432. As typically shown in FIG. 9, the substrate support 426 can be coupled to the alignment unit 412. Thus, the substrate moves relative to the mask 432 to provide accurate alignment between the substrate and the mask during material deposition, which can be beneficial for high quality display manufacturing. Alternatively or additionally, mask 432 and / or mask frame 431 holding mask 432 may be coupled to alignment unit 412. Accordingly, either the mask 432 can be positioned relative to the substrate 444, or both the mask 432 and the substrate 444 can be positioned relative to each other.

  As shown in FIG. 9, the linear guide 420 may provide the direction of translational movement of the evaporation source 300. A mask 432 may be provided on both sides of the evaporation source 300. The mask may extend substantially parallel to the direction of translation. Further, the opposing substrate of the evaporation source 300 can also extend essentially parallel to the direction of translation. As typically shown in FIG. 9, the evaporation source 300 provided in the vacuum chamber 410 of the deposition apparatus 400 can include a support 302 that can be configured for translational movement along a linear guide 420. For example, the support 302 can support two evaporation crucibles and two distribution pipes 320 provided on the evaporation crucible 310. Thereby, the vapor | steam produced | generated with the evaporation crucible can move upwards from the one or some discharge port of distribution pipe.

  As illustrated in FIG. 9, the deposition source may be provided with two or more distribution pipes. For example, two or more distribution pipes can be designed in a triangular shape. The triangular distribution pipe 320 may be advantageous when two or more distribution pipes are arranged next to each other. In particular, the triangular distribution pipe 320 allows the outlets of the evaporating material of adjacent distribution pipes to be as close as possible to each other. This can improve the mixing of different materials from different distribution pipes, for example in the case of co-evaporation of two, three or more different materials.

  Accordingly, a method, a deposition rate control system, an evaporation source and a deposition apparatus for measuring a deposition rate of an evaporating material according to embodiments described herein provide improved deposition rate measurement and / or improved deposition rate control. I will provide a. This can be advantageous for high quality display manufacturing, eg high quality OLED manufacturing.

Claims (15)

A method (100) for measuring a deposition rate of evaporating material comprising:
Measuring the deposition rate at a time interval between a first measurement and a second measurement (110) , the time interval from the end of the first measurement to the second measurement; Measuring, defined by the time to start ,
Adjusting the time interval depending on the measured deposition rate (120).     The measurement method (100) of claim 1, wherein the dependence on the measured deposition rate is a function of the deposition rate.     The measured deposition rate function is the slope of the deposition rate, a Boolean determination of the deposition rate within a predetermined range, the polynomial function of the difference of the measured deposition rate to the nominal / set value of the predetermined deposition rate And a measurement method (100) according to claim 1 or 2, selected from the group consisting of an oscillation function of the measured deposition rate.   4. The measurement method according to claim 1, further comprising shielding (130) a deposition rate measuring device from the evaporation material between the first measurement and the second measurement. 5. 100).   The shielding (130) opens a shutter (213) between the deposition rate measuring device (211) and a measurement outlet (230) for supplying the evaporated material to the deposition rate measuring device (211). The measurement method (100) according to claim 4, comprising moving.   6. The method of any one of claims 1-5, further comprising cleaning (140) a deposition rate measuring device (211) from a deposition material between the first measurement and the second measurement. Measurement method (100).   The measurement method (100) of claim 6, wherein the cleaning (140) comprises evaporating the deposition material from the deposition rate measurement device (211).   The measurement method (100) according to claim 7, wherein evaporating the deposition material from the deposition rate measuring device (211) is performed by heating the deposition rate measuring device. A deposition rate measurement assembly (210) for measuring the deposition rate of the evaporating material;
A controller (220) coupled to the deposition rate measurement assembly (210) and an evaporation source (300), wherein the controller is configured to provide a control signal to the deposition rate measurement assembly (210). ,
The deposition rate control system (200), wherein the controller is configured to execute program code, and when the program code is executed, the method of claims 1-8 is executed.   The deposition rate control system (200) of claim 9, wherein the controller (220) comprises a closed loop control including at least one proportional integral derivative (PID) controller for controlling the deposition rate.   11. The deposition rate control system (200) of claim 9 or 10, wherein the deposition rate measurement assembly (210) comprises a deposition rate measurement device (211) that includes an oscillating crystal (212) for measuring the deposition rate. .   The deposition rate measurement assembly (210) shields the deposition rate measurement device (211) from the evaporation material supplied from a measurement outlet (230) for supplying evaporation material to the deposition rate measurement device (211). A deposition rate control system (200) according to any one of claims 9 to 11, comprising a movable shutter (213).   At least one heating element (214) for heating the deposition rate measuring device (211) to a temperature at which the deposition rate measuring assembly (210) evaporates the material deposited on the deposition rate measuring device (211). The deposition rate control system (200) according to any one of claims 9 to 12, comprising: An evaporation crucible (310) configured to evaporate material;
A distribution pipe (320) having one or more outlets provided along the length of a distribution pipe for supplying the evaporation material to the substrate at a deposition rate, and in fluid communication with the evaporation crucible (310) An evaporation source (300) for material evaporation comprising a distribution pipe (320) and a deposition rate control system (200) according to any one of claims 9 to 13.   A deposition apparatus (400) for applying material to a substrate (444) in a vacuum chamber (410) at a deposition rate, comprising at least one evaporation source (300) according to claim 14.

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