CN-120740662-B - Photoresist filling state monitoring system and method

CN120740662BCN 120740662 BCN120740662 BCN 120740662BCN-120740662-B

Abstract

The invention relates to the technical field of industrial process state monitoring, in particular to a photoresist filling state monitoring system and a photoresist filling state monitoring method; the system comprises a micro-pressure pulse control unit, an acoustic perception judging unit, a multi-channel intelligent decision unit, a data recording unit and an end point judging and feedback information recording unit, wherein the micro-pressure pulse control unit is used for collecting reflected pressure change signals, establishing a corresponding relation between the length of a liquid column and the pressure and outputting a pressure fracture judging result, the acoustic perception judging unit is used for collecting liquid column fracture sound pressure signals, constructing a non-contact liquid column end point state identifying mechanism and outputting an acoustic fracture judging result, the multi-channel intelligent decision unit is used for judging whether the pressure fracture judging result is true or false by using a two-state appearance suspicious self-evidence mechanism and combining the acoustic fracture judging result to output a final liquid column fracture judging signal, and the data recording unit is used for recording end point judging related parameters, fracture judging results and end point control feedback information in each filling process. According to the invention, through combining micro-pressure pulse application and reflected pressure signal analysis and introducing acoustic judgment, the end point state of the liquid column at the tail end of photoresist filling is accurately monitored.

Inventors

ZHOU CHUN
ZHAO GUOFEI
WANG FEI
TANG CHUNMING

Assignees

合肥孚烜自动化科技有限公司

Dates

Publication Date: 20260508
Application Date: 20250805

Claims (9)

1. A photoresist filling state monitoring system, comprising: The micro-pressure pulse control unit (1), the micro-pressure pulse control unit (1) is used for applying micro-pressure pulse to the filling pipeline, collecting reflected pressure change signals, establishing a corresponding relation between the length of the liquid column and the pressure, sending out a fracture triggering instruction when the length of the liquid column is close to a threshold value interval of the critical length, and outputting a pressure fracture judgment result of the fracture state of the liquid column; The acoustic sensing judging unit (2) is used for collecting liquid column fracture sound pressure signals, calculating sound spectrum energy change, amplitude fluctuation rate and duration time indexes, constructing a non-contact liquid column endpoint state identifying mechanism and outputting an acoustic fracture judging result of the liquid column fracture state; The multichannel intelligent decision unit (3) dynamically judges whether the pressure fracture judgment result is true or false by using a binary suspicious self-evidence mechanism and outputs a final liquid column fracture judgment signal by combining the acoustic fracture judgment result; In the multichannel intelligent decision unit (3), a two-state suspicious self-certification mechanism is used for carrying out credibility evaluation on a pressure fracture judgment result, actively identifying a potential erroneous judgment mode, and carrying out auxiliary judgment and verification on the liquid column fracture state by combining an acoustic fracture judgment result when the pressure fracture judgment result is identified as unreliable; and the filling process data recording unit (4) is used for recording the related parameters of end point judgment, the fracture judgment result and the end point control feedback information in each filling process.
2. The photoresist filling state monitoring system according to claim 1, wherein the micro-pressure pulse is a periodic disturbance signal with amplitude lower than a hydrostatic pressure value of a liquid column and pulse width smaller than 1 second, and is used for realizing the disturbance of the liquid column state, and the micro-pressure pulse is applied to the filling pipeline according to a micro-pressure pulse frequency setting rule and a pressure applying period adjustment strategy.
3. The photoresist filling state monitoring system of claim 2, wherein the reflected pressure change signal comprises an initial echo response value, a multi-order decaying echo amplitude sequence, and echo delay change data for determining whether the liquid column is near a break; in the micro-pressure pulse control unit (1), a corresponding relation between the length of a liquid column and the pressure is established, and the specific method comprises the following steps: Segmenting the reflected pressure change signals according to pulse numbers, and mapping each segment of reflected pressure change signals to an interval segment of a liquid column length range correspondingly to form a pressure length precalibrated data set; the multivariable nonlinear mapping function is used for estimating the length of the liquid column in real time according to the reflected pressure change signals.
4. A photoresist filling state monitoring system according to claim 3, wherein the micropressure pulse control unit (1) performs a judgment comparison between the real-time estimated liquid column length of the multivariable nonlinear mapping function and the threshold length interval when the liquid column length is close to the threshold length interval, and issues a fracture triggering instruction when one of the fracture triggering conditions is satisfied; The fracture triggering condition is that the length of the liquid column enters a threshold interval of critical length for the first time, and no increasing trend occurs in two continuous pulse periods; The fracture triggering instruction is used for starting a fracture state identification process and outputting a pressure fracture judgment result of a liquid column fracture state, and the pressure fracture judgment result comprises a liquid column fracture state marker bit and a fracture occurrence time pulse number.
5. The photoresist filling state monitoring system according to claim 4, wherein the acoustic perception discriminating unit (2) performs a sectional processing on the collected liquid column breaking sound pressure signal, and calculates the indexes of the sound spectrum energy change, the amplitude fluctuation rate and the duration of the liquid column breaking sound pressure signal, respectively, and the specific calculation method is as follows: The method comprises the steps of carrying out time-frequency analysis on a liquid column fracture sound pressure signal in a target frequency band, extracting a total amplitude change trend of a frequency domain, differentiating the total amplitude change trend with a static background sound spectrum, calculating to obtain sound spectrum energy change, extracting an envelope curve of the liquid column fracture sound pressure signal, counting the amplitude change times in unit time to obtain an amplitude fluctuation rate, and determining a duration interval of a liquid column fracture event according to a start-stop time interval of a continuous high-amplitude section in the liquid column fracture sound pressure signal to obtain a duration index.
6. The photoresist filling state monitoring system according to claim 5, wherein the non-contact liquid column endpoint state recognition mechanism is constructed based on fusion of sonographic energy change, amplitude fluctuation rate and duration time index, and is used for recognizing whether the liquid column reaches a fracture state and judging whether a back suction residue and a dragline non-breakage phenomenon exist; The specific construction method of the non-contact liquid column end point state identification mechanism comprises the following steps: Calculating the indexes of the sound spectrum energy change, the amplitude fluctuation rate and the duration of the sound pressure signals of the breaking of the liquid column of the photoresist filling for a plurality of times, constructing the indexes of the sound spectrum energy change, the amplitude fluctuation rate and the duration obtained by each calculation into three-dimensional characteristics, marking the breaking state of the liquid column of the photoresist filling each time, training the three-dimensional characteristics by adopting a supervision multi-classification judging method, constructing a state identification classification model, inputting the three-dimensional characteristics of the breaking sound pressure signals of the liquid column of the photoresist filling into the state identification classification model in real time in the filling process, outputting the breaking state of the liquid column of the photoresist filling in real time, and obtaining the acoustic breaking judging result of the breaking state of the liquid column.
7. The photoresist filling state monitoring system according to claim 6, wherein the misjudgment recognition model is constructed based on a multidimensional feature matching strategy, is used for constructing a suspicion analysis vector based on a pressure fracture judgment result and filling history data, and outputs a suspicion score representing the credibility degree of the pressure fracture judgment result; The multi-dimensional abnormal characteristic combination comprises a pressure fluctuation amplitude, a disturbance peak response time, waveform oscillation symmetry, an echo attenuation gradient and a disturbance response time delay; the suspicion score is a nonlinear matching error between suspicion analysis vector and the characteristics of the historical normal fracture sample, and is used for judging whether the pressure fracture judgment result is misjudgment or not.
8. The photoresist filling state monitoring system of claim 7, wherein the acoustic compensation module is configured to analyze whether the suspicion score exceeds a set threshold, and when the suspicion score exceeds the set threshold, to enable an acoustic break determination result to replace a pressure break determination result, and to output a final liquid column break determination signal.
9. A method for monitoring the filling state of photoresist, which is used for the monitoring system of the filling state of the photoresist according to any one of claims 1 to 8, and is characterized by comprising the following steps: s10.1, applying micro-pressure pulse to a filling pipeline, collecting reflected pressure change signals, establishing a corresponding relation between the length of a liquid column and pressure, sending out a fracture triggering instruction when the length of the liquid column is close to a threshold interval of a critical length, and outputting a pressure fracture judgment result of a fracture state of the liquid column; s10.2, collecting a liquid column fracture sound pressure signal, calculating the indexes of sound spectrum energy change, amplitude fluctuation rate and duration time to construct a non-contact liquid column endpoint state identification mechanism, and outputting an acoustic fracture judgment result of the liquid column fracture state; S10.3, dynamically judging whether the pressure fracture judgment result is true or false by using a binary appearance suspicious self-evidence mechanism, and outputting a final liquid column fracture judgment signal by combining the acoustic fracture judgment result; The double-state appearance suspicious self-certification mechanism is used for carrying out credibility evaluation on the pressure fracture judgment result, actively identifying a potential misjudgment mode, and carrying out auxiliary judgment verification on the liquid column fracture state by combining the acoustic fracture judgment result when the pressure fracture judgment result is identified as unreliable; s10.4, recording relevant parameters of end point judgment, fracture judgment results and end point control feedback information in each filling process.

Description

Photoresist filling state monitoring system and method Technical Field The invention relates to the technical field of industrial process state monitoring, in particular to a photoresist filling state monitoring system and method. Background The photoresist is a key photosensitive material widely used in precise processes such as semiconductor manufacture, micro-nano processing and the like, and the filling process has direct influence on the quality and production stability of finished products, particularly in the last stage of conveying the photoresist from a storage container to a sub-packaging container through a pipeline, the change of the liquid column state is sensitive and has complex influence factors, the accuracy of end point judgment is not only related to the consistency of single filling volume, but also directly influences the uniformity and stability of the subsequent gluing process, so that how to accurately identify the breaking state of the liquid column in the last stage of filling is an important technical link in the control of the filling quality of the photoresist; in the process of photoresist filling approaching the end stage, the problems that photoresist liquid has higher viscosity and lower flow speed, when pressure signal feedback analysis is adopted, feedback of pressure signals is easy to be interfered by bubble retention, tail liquid backflow, micro vibration of the inner wall of a pipeline and other non-fracture factors, the factors possibly form a fluctuation mode similar to real fracture in a pressure reflection signal, so that misjudgment is caused, meanwhile, the real fracture pressure signals can not be reflected immediately due to conduction delay, so that a liquid column is broken but still judged to be a non-broken misjudgment condition, and in the second end judgment, the response characteristics of the pressure signals and acoustic signals to the fracture are different, and when the two mutually conflicting judgment results are generated at the same moment, if the two results cannot be confirmed timely, the wrong end signals can be directly output, so that the problems of multi-filling, under-filling or liquid drop residue and the like are solved, and adverse effects are caused on the quality and the production stability of the photoresist. Disclosure of Invention The invention aims to provide a photoresist filling state monitoring system and a photoresist filling state monitoring method, so as to solve the problem that the accurate filling of photoresist is affected by the two problems in the background technology. To achieve the above object, the present invention provides a photoresist filling state monitoring system, comprising: The micro-pressure pulse control unit is used for applying micro-pressure pulses to the filling pipeline, collecting reflected pressure change signals, establishing a corresponding relation between the length of the liquid column and the pressure, sending out a fracture triggering instruction when the length of the liquid column is close to a threshold interval of a critical length, and outputting a pressure fracture judgment result of a fracture state of the liquid column; The acoustic sensing judging unit is used for collecting liquid column fracture sound pressure signals, calculating sound spectrum energy change, amplitude fluctuation rate and duration time indexes, constructing a non-contact liquid column endpoint state identifying mechanism and outputting an acoustic fracture judging result of the liquid column fracture state; the multichannel intelligent decision unit dynamically judges whether the pressure fracture judgment result is true or false by using a binary suspicious self-evidence mechanism and outputs a final liquid column fracture judgment signal by combining the acoustic fracture judgment result; And the filling process data recording unit is used for recording the related parameters of end point judgment, the fracture judgment result and the end point control feedback information in each filling process. Preferably, the micro-pressure pulse is a periodic disturbance signal with amplitude lower than the hydrostatic pressure value of the liquid column and pulse width smaller than 1 second, and is used for realizing the disturbance of the liquid column state, and the micro-pressure pulse is applied to the filling pipeline according to the micro-pressure pulse frequency setting rule and the pressure applying period adjusting strategy. Preferably, the reflected pressure change signal comprises an initial echo response value, a multi-order attenuation echo amplitude sequence and echo time delay change data, and is used for judging whether the liquid column is close to fracture; In the micro-pressure pulse control unit, a corresponding relation between the length of the liquid column and the pressure is established, and the specific method comprises the following steps: Segmenting the reflected pressure change signals ac