Method for monitoring residual mass of crucible material
By determining the consumption coefficient before evaporation and using a film thickness gauge to monitor the evaporation rate, the problem of inaccurate monitoring of the remaining material in the crucible is solved, achieving high-precision monitoring of the remaining material mass in the crucible and ensuring the stability of the coating process and product quality.
Patent Information
- Application Number
- CN202511827761.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-05
- Publication Date
- 2026-03-03
Smart Images
Figure CN121592998A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of vapor deposition system technology, and in particular to a method for monitoring the residual mass of crucible material. Background Technology
[0002] In vacuum evaporation processes, the crucible, as the core component that supports and heats the evaporation source (such as metals or organic materials), directly affects the stability of the coating process and the quality of the final product. If the material is depleted and not replenished in time, it will lead to serious defects such as film interruption and uneven thickness, resulting in a huge waste of substrate material, time, and energy.
[0003] Currently, the industry mainly relies on two traditional methods to monitor the amount of material remaining in the crucible.
[0004] The first method is the experience-based estimation method, where operators estimate the amount of material needed to deposit a certain film thickness based on historical data and production experience. This method relies heavily on the operator's personal experience, lacks objective and precise quantitative standards, and cannot adapt to changes in process parameters such as raw material purity and evaporation temperature fluctuations. Therefore, it has low reliability, large errors, and cannot achieve accurate early warning.
[0005] Another method is the gravimetric method, which typically involves installing a weight sensor (such as a piezoelectric sensor) at the bottom of the crucible. The material consumption is inferred by measuring the overall weight change of the crucible in real time. However, the accuracy of this gravimetric method is greatly affected by environmental factors. In particular, the vapor deposition process is usually carried out at high temperatures of several hundred degrees Celsius. Weight sensors can experience severe signal drift or even damage at temperatures exceeding 500°C, leading to inaccurate measurements. Furthermore, since this method measures the total weight of the crucible system, it cannot distinguish between material consumption and weight changes caused by thermal expansion and contraction or the application of coatings, resulting in low reliability and large errors. Summary of the Invention
[0006] To address the shortcomings of existing technologies, the purpose of this application is to provide a method for monitoring the remaining mass of crucible material, thereby improving the accuracy and reliability of detecting the remaining mass of material inside the crucible.
[0007] To achieve the above objectives, this application provides a method for monitoring the residual mass of crucible material, comprising: Before formally vaporizing the evaporation source material, conduct at least one vaporization experiment to determine the thickness and weight of the consumed evaporation source material after the vaporization experiment. Based on the thickness of the vapor-deposited material and the required material weight, the consumption coefficient per unit thickness is determined; The crucible is filled with a predetermined mass of evaporation source material, and the formal evaporation deposition begins. Based on the predetermined mass of the evaporation source material, the consumption coefficient, and the consumed thickness of the evaporation source material detected in each evaporation deposition, the remaining mass of the evaporation source material is determined in real time.
[0008] Furthermore, the thickness of the evaporation source material consumed is determined by the evaporation time and evaporation rate during each evaporation process.
[0009] Furthermore, a film thickness gauge was used to monitor the evaporation rate during the vapor deposition process.
[0010] Furthermore, the method also includes: For the same evaporation source material, several evaporation deposition experiments were conducted. Based on the consumption coefficient per unit thickness calculated after each vapor deposition experiment, the average or fitted value is taken as the consumption coefficient per unit thickness used in the formal vapor deposition.
[0011] Furthermore, the method also includes: Evaporation experiments were conducted for different evaporation source materials to determine the consumption coefficient per unit thickness for different evaporation source materials. Based on the type of evaporation source material used in the formal vapor deposition, the corresponding consumption coefficient per unit thickness is selected, and the remaining mass of the evaporation source material is determined in real time.
[0012] Furthermore, the method also includes: When the remaining mass of the evaporation source material is less than the predetermined remaining amount threshold, an alarm is issued and the evaporation source material is added.
[0013] Furthermore, the remaining amount threshold is the minimum mass required for one vapor deposition.
[0014] Furthermore, the evaporation source material is a metal or an organic substance.
[0015] To achieve the above objectives, this application also provides a system for monitoring the residual mass of crucible material, comprising: The monitoring unit is used to detect the evaporation rate and evaporation time of the evaporation source material in real time during each vapor deposition process; The calculation unit, connected to the monitoring unit, is used to calculate the remaining mass of the evaporation source material in the crucible based on the evaporation rate and evaporation time of the evaporation source material in each evaporation process, using the consumption coefficient per unit thickness corresponding to the evaporation source material. An early warning unit, connected to the computing unit, is used to issue an early warning when the remaining mass is less than a preset remaining quantity threshold.
[0016] To achieve the above objectives, this application also provides a vapor deposition apparatus, including a crucible and a monitoring system for the remaining mass of crucible material as described above.
[0017] This application discloses a method for monitoring the remaining mass of crucible material. By monitoring the evaporation thickness with a film thickness gauge and calculating the material consumption, a precise mathematical relationship between film thickness and consumption is established. This method overcomes the measurement errors caused by high-temperature thermal drift and mechanical vibration in traditional weighing methods, as well as the subjectivity and inaccuracy of empirical estimation methods, and achieves high-precision, digital monitoring of the remaining mass of crucible material.
[0018] This application discloses a method for monitoring the remaining mass of crucible material, which can accurately predict the mass of the remaining material and issue an early warning before the material is actually exhausted. This allows operators to plan production and maintenance in a more efficient manner, effectively avoiding defects in film quality, product scrap, and unplanned production interruptions caused by the sudden exhaustion of material.
[0019] This application discloses a method for monitoring the remaining mass of crucible materials. Through experiments, the "consumption coefficient" for different materials can be easily obtained and calibrated. It can be quickly adapted to various evaporation materials and process formulations, and has strong versatility.
[0020] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing this application. Attached Figure Description
[0021] The accompanying drawings are provided to further illustrate the present application and form part of the specification. Together with the embodiments of the present application, they serve to explain the present application but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic flowchart of the method for monitoring the remaining mass of crucible material according to Embodiment 1 of this application; Figure 2 This is a schematic diagram of the architecture of the crucible material residual mass monitoring system of Embodiment 2 of this application. Detailed Implementation
[0022] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While some embodiments of this application are shown in the drawings, it should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this application. It should be understood that the drawings and embodiments of this application are for illustrative purposes only and are not intended to limit the scope of protection of this application.
[0023] It should be understood that the steps described in the method embodiments of this application may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of this application is not limited in this respect.
[0024] The term "comprising" and its variations as used herein are open-ended inclusions, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below.
[0025] It should be noted that the terms "one" and "multiple" used in this application are illustrative rather than restrictive, and those skilled in the art should understand that, unless explicitly stated otherwise in the context, they should be understood as "one or more". "Multiple" should be understood as two or more.
[0026] The embodiments of this application will now be described in detail with reference to the accompanying drawings.
[0027] Example 1 One embodiment of this application provides a method for monitoring the remaining mass of crucible material. Figure 1 This is a schematic flowchart of the method for monitoring the remaining mass of crucible material according to Embodiment 1 of this application, as shown below. Figure 1 As shown, the method for monitoring the residual mass of crucible material in this application includes: Step S101: Before formally evaporating the evaporation source material, conduct at least one evaporation experiment to determine the thickness of the evaporation source material consumed and the weight of the evaporation source material consumed after the evaporation experiment. For example, the process of a vapor deposition experiment is as follows: A portion of pure evaporation source material is weighed using a high-precision electronic balance (accuracy 0.001g), and its mass is recorded as W1. This mass is carefully filled into a clean crucible. The vapor deposition process is started, and the temperature is slowly increased using the crucible heating system to allow the evaporation source material to begin stable evaporation. During the evaporation process, a film thickness gauge is used to monitor the evaporation rate and deposition time. After the deposition is completed, the crucible and cavity are allowed to cool to room temperature. The crucible is then removed, and the total mass of the crucible and the remaining evaporation source material is weighed using the same high-precision electronic balance. To eliminate the possibility of contamination or weight changes in the crucible itself, the mass of the previously known empty crucible is subtracted, thereby calculating the mass W2 of the remaining evaporation source material. Based on the evaporation rate R and deposition time t during the deposition process, the thickness D consumed by the vapor deposition is calculated.
[0028] A film thickness gauge is used to monitor the evaporation rate during vapor deposition. The film thickness (unit: Å) is equal to the evaporation rate (unit: Å / S) multiplied by the evaporation time.
[0029] Step S102: Determine the consumption coefficient per unit thickness based on the thickness of the evaporation source material and the required material weight; Since the mass of the evaporation source material consumed for thickness D has been calculated as W1-W2, the consumption coefficient N can be calculated, that is, the mass per unit thickness is (W1-W2) / D.
[0030] In this embodiment of the application, in order to ensure the accuracy of the consumption coefficient, the evaporation experiment is repeated multiple times, and the arithmetic average of the consumption coefficients obtained from the multiple calculations is used as the final calibrated consumption coefficient of the evaporation source material.
[0031] In the embodiments of this application, vapor deposition experiments are conducted for different evaporation source materials to establish a consumption coefficient database covering a variety of evaporation source materials (such as metal evaporation source materials Al, Ag, etc. and organic materials P3HT, PTB7, PCBM, ITIC, etc.). During the formal vapor deposition, the corresponding consumption coefficient per unit thickness is selected according to the type of evaporation source material used.
[0032] Step S103: Fill the crucible with a predetermined mass of evaporation source material and begin the formal evaporation process; According to the vapor deposition requirements, a predetermined mass of evaporation source material is filled into the crucible, and the corresponding consumption coefficient per unit thickness is selected. The remaining amount threshold is set, and the formal vapor deposition begins. The vapor deposition process is repeated cyclically.
[0033] In this embodiment of the application, the remaining amount threshold is the minimum mass required for one vapor deposition.
[0034] Step S104: Based on the predetermined mass of the evaporation source material, the consumption coefficient, and the consumed thickness of the evaporation source material detected in each evaporation deposition, determine the remaining mass of the evaporation source material in real time; During the vapor deposition process, a film thickness gauge monitors the evaporation rate and deposition time for each deposition cycle, calculating the thickness and mass consumed in each cycle. This allows for real-time determination of the remaining mass of the evaporation source material after each deposition. If the remaining mass of the evaporation source material falls below a predetermined threshold, an alert is issued, and additional evaporation source material is added.
[0035] Example 2 One embodiment of this application provides a system for monitoring the remaining mass of crucible material. Figure 2 This is a schematic diagram of the architecture of the crucible material residual mass monitoring system of Embodiment 2 of this application, as shown below. Figure 2 As shown, the crucible material residual mass monitoring system of this application includes: Monitoring unit 100 is used to detect the evaporation rate and evaporation time of the evaporation source material in each vapor deposition process in real time; In this embodiment, the monitoring unit 100 is a quartz crystal film thickness gauge, which monitors the change in the inherent frequency of the crystal oscillator caused by material deposition, and calculates and outputs the instantaneous evaporation rate in real time.
[0036] The calculation unit 200, connected to the monitoring unit 100, is used to calculate the consumed mass and remaining mass of the evaporation source material in the crucible based on the evaporation rate and evaporation time of the evaporation source material in each evaporation process, using the consumption coefficient of the unit thickness corresponding to the evaporation source material. In this application, the computing unit 200 is an industrial control computer or a high-performance programmable logic controller (PLC).
[0037] Understandably, the computing unit 200 is generally equipped with a human-machine interface to display real-time data such as evaporation rate, cumulative film thickness, consumption, and remaining mass, as well as to set the remaining amount threshold, select the consumption coefficient, and control the issuance of audible and visual alarms.
[0038] In this embodiment of the application, the calculation unit 200 pre-stores the consumption coefficients of several evaporation source materials per unit thickness obtained through experiments, so as to select and calculate the remaining mass during the formal evaporation process.
[0039] The early warning unit 300, connected to the calculation unit 200, is used to issue an early warning when the remaining mass is less than a preset remaining quantity threshold.
[0040] In this embodiment of the application, the early warning unit 300 can be an audible and visual alarm.
[0041] The above description is merely a partial embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.
[0042] Furthermore, while the operations are described in a specific order, this should not be construed as requiring these operations to be performed in the specific order shown or in sequential order. Multitasking and parallel processing may be advantageous in certain environments. Similarly, while several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of this application. Certain features described in the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.
[0043] Although the subject matter has been described using language specific to structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.
Claims
1. A method for monitoring the remaining mass of crucible material, characterized in that, include: Before formally vaporizing the evaporation source material, conduct at least one vaporization experiment to determine the thickness and weight of the consumed evaporation source material after the vaporization experiment. Based on the thickness of the vapor-deposited material and the required material weight, the consumption coefficient per unit thickness is determined; The crucible is filled with a predetermined mass of evaporation source material, and the formal evaporation deposition begins. Based on the predetermined mass of the evaporation source material, the consumption coefficient, and the consumed thickness of the evaporation source material detected in each evaporation deposition, the remaining mass of the evaporation source material is determined in real time.
2. The method for monitoring the remaining mass of crucible material according to claim 1, characterized in that, The thickness of the evaporation source material consumed is determined by the evaporation time and evaporation rate during each evaporation process.
3. The method for monitoring the remaining mass of crucible material according to claim 1, characterized in that, The evaporation rate during vapor deposition was monitored using a film thickness gauge.
4. The method for monitoring the remaining mass of crucible material according to claim 2, characterized in that, The method further includes: For the same evaporation source material, several evaporation deposition experiments were conducted. Based on the consumption coefficient per unit thickness calculated after each vapor deposition experiment, the average or fitted value is taken as the consumption coefficient per unit thickness used in the formal vapor deposition.
5. The method for monitoring the remaining mass of crucible material according to claim 3, characterized in that, The method further includes: Evaporation experiments were conducted for different evaporation source materials to determine the consumption coefficient per unit thickness for different evaporation source materials. Based on the type of evaporation source material used in the formal vapor deposition, the corresponding consumption coefficient per unit thickness is selected, and the remaining mass of the evaporation source material is determined in real time.
6. The method for monitoring the remaining mass of crucible material according to claim 2, characterized in that, The method further includes: When the remaining mass of the evaporation source material is less than the predetermined remaining amount threshold, an alarm is issued and the evaporation source material is added.
7. The method for monitoring the remaining mass of crucible material according to claim 1, characterized in that, The remaining amount threshold is the minimum mass required for one vapor deposition.
8. The method for monitoring the remaining mass of crucible material according to claim 6, characterized in that, The evaporation source material is a metal or an organic substance.
9. A system for monitoring the remaining mass of crucible material, characterized in that, include: The monitoring unit is used to detect the evaporation rate and evaporation time of the evaporation source material in real time during each vapor deposition process; The calculation unit, connected to the monitoring unit, is used to calculate the consumed mass and remaining mass of the evaporation source material in the crucible based on the evaporation rate and evaporation time of the evaporation source material in each evaporation process, using the consumption coefficient of the unit thickness corresponding to the evaporation source material. An early warning unit, connected to the computing unit, is used to issue an early warning when the remaining mass is less than a preset remaining quantity threshold.
10. A vapor deposition apparatus, characterized in that, Includes a crucible and a monitoring system for the remaining mass of the crucible material as described in claim 9.