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CN-121979086-A - Dust-free control system of semiconductor ultra-trace analysis laboratory

CN121979086ACN 121979086 ACN121979086 ACN 121979086ACN-121979086-A

Abstract

The invention discloses a dust-free control system of a semiconductor ultra-trace analysis laboratory, and belongs to the technical field of clean room control. The system comprises an environment sensing layer, a central control processing layer, an executing mechanism layer and an upper computer monitoring terminal. The invention designs a pressure control module based on the integration of chemical logic and clean logic aiming at the characteristics of rapid exhaust change and high cleanliness requirement of a semiconductor laboratory fume hood, and realizes millisecond-level air supply compensation by detecting the height of a window to prevent polluted air from flowing backwards. Meanwhile, the system introduces a visual energy-saving control module of a matrix fan filtering unit, combines the feedback of a particle counter, and dynamically adjusts the running number of fans by adopting a checkerboard or quincuncial pile distribution model. The invention effectively solves the conflict of exhaust safety and stable cleanliness, realizes precise control and remarkable energy saving of laboratory environment, and is suitable for the field of semiconductor analysis with extremely high requirements on environmental indexes.

Inventors

  • ZHANG JUNFENG
  • Miao Qizhen

Assignees

  • 苏州赛米肯分析技术有限公司

Dates

Publication Date
20260505
Application Date
20260206

Claims (10)

  1. 1. A semiconductor ultra trace analysis laboratory dust-free control system, comprising: the environment sensing layer is used for collecting environment parameters inside and outside a laboratory, and the environment parameters at least comprise micro-pressure difference, temperature and humidity, suspended particle concentration and state data of the fume hood; The execution mechanism layer is used for adjusting the air supply, the air exhaust and the cleanliness of a laboratory and comprises a fan filter unit array, a fresh air unit, an air exhaust variable air volume valve and a water cooling unit pump set; A central control processing layer connected with the environment sensing layer and the executing mechanism layer for executing control logic and issuing control instructions based on the collected environment parameters, and The upper computer monitoring terminal is used for providing a visual human-computer interaction interface; The system comprises a central control processing layer, a chemical logic and clean logic fusion-based pressure control module and a matrix type fan filter unit visual energy-saving control module, wherein the pressure control module is configured to switch between a chemical priority mode and a clean priority mode so as to coordinate the exhaust demand of a fume hood and the indoor pressure difference stability, and the matrix type fan filter unit visual energy-saving control module is configured to dynamically adjust the operation distribution model of a fan filter unit array according to the cleanliness demand.
  2. 2. The ultra trace analysis laboratory dust-free control system according to claim 1, wherein the pressure control module executes a feed-forward control strategy in a chemical priority mode, when the environmental perception layer detects that the window height of the fume hood is changed, the central control processing layer calculates an expected exhaust increment according to the product of the window opening area and the set surface wind speed, and directly sends an instruction for increasing the air supply quantity to the fresh air handling unit before the micro-pressure difference value is changed.
  3. 3. The ultra trace analysis laboratory dust free control system according to claim 1, wherein the pressure control module performs a feedback control strategy in a clean priority mode, wherein the central control processing layer calculates an output quantity by a proportional integral derivative algorithm with a real-time measurement value of micro pressure difference as a process variable, and the output quantity acts on the overall rotation speed adjustment of the fan filter unit array and the opening adjustment of the return air valve simultaneously to maintain micro positive pressure of the laboratory relative to an external area.
  4. 4. The system of claim 1, wherein the upper computer monitor terminal is configured with an FFU array visual interaction module, the interface of the module comprises a rectangular primitive array corresponding to the actual physical layout, each primitive is mapped with a fan filter unit with independent address codes, the visual interaction module is configured to display the operation state of the corresponding unit by changing the primitive color, and support single-point start-stop or speed regulation control of the specific fan filter unit by clicking the primitive.
  5. 5. The ultra trace analysis laboratory dust free control system according to claim 4, wherein the matrix fan filter unit visualization energy saving control module is configured to automatically calculate a minimum air supply and a minimum number of operating units required to maintain a target cleanliness level when a suspended particle concentration collected by an environmental perception layer is below a set threshold, and generate an opening scheme, wherein the opening scheme comprises a checkerboard distribution model or a quincuncial pile distribution model.
  6. 6. The system of claim 5, wherein the checkerboard distribution model controls the fan filter unit array to start only units in odd rows and odd columns or even rows and even columns, the quincuncial pile distribution model controls the fan filter unit array to start units according to a sparse distribution rule, and the central control processing layer controls the unopened units to enter an idle running state or a stopping state.
  7. 7. The semiconductor ultra trace analysis laboratory dust-free control system according to claim 1, wherein the central control processing layer is further provided with a precise water-cooling unit control module, the water-cooling unit pump set comprises a working pump, a standby pump and a frequency converter, the precise water-cooling unit control module collects pressure signals of a water supply pipeline, and the rotation speed of the working pump is controlled by adjusting the output frequency of the frequency converter so as to maintain the constant water supply pressure.
  8. 8. The semiconductor ultra trace analysis laboratory dust free control system according to claim 1, wherein said environmental awareness layer comprises a micro-pressure differential sensor mounted between the laboratory and adjacent areas, an on-line particle counter disposed above the experimental operation area, and a face wind speed sensor and window height sensor mounted on a fume hood, wherein the sampling flow rate of said on-line particle counter is set to two points eight three liters per minute or one cubic foot per minute.
  9. 9. The system of claim 1, wherein each fan filter unit comprises a variable speed fan, a high efficiency air filter and an address coding module, the address coding module is connected with the central control processing layer through a communication bus, and the high efficiency air filter is an ultra-low penetration air filter with the filtering efficiency of no less than ninety-nine percent for zero-point three-micron particles.
  10. 10. The system of claim 1, wherein the upper computer monitor terminal is configured with a data trend tracing module for recording and tracing historical data curves including temperature, relative humidity, indoor and outdoor pressure differences and particle count values, wherein the recording period is configurable, and the storage time period is several weeks to several months.

Description

Dust-free control system of semiconductor ultra-trace analysis laboratory Technical Field The invention relates to the technical field of clean room environment control, in particular to a dust-free control system of a semiconductor ultra-trace analysis laboratory. Background The semiconductor ultra trace analysis laboratory is mainly used for detecting trace metal impurities in semiconductor materials and process chemicals, has extremely severe requirements on environmental cleanliness, and generally meets the standard of ISO 5 grade (hundred grade) or even higher. Meanwhile, in order to ensure the safety of laboratory staff in treating strong acid, strong alkali and volatile organic solvents, a plurality of large-air-volume fume hoods are required to be arranged in the laboratory. The existing laboratory control system often faces the technical problem of control logic conflict when processing the requirements of high cleanliness and high exhaust air quantity. The traditional control mode mostly adopts a single feedback loop (PID control) based on a differential pressure sensor, namely when the ventilation quantity of the ventilation cabinet changes to cause the fluctuation of indoor differential pressure, the system adjusts the fresh air quantity to compensate. However, in semiconductor analysis experiments, the operation of pulling the window of the fume hood by the experimenter tends to be very rapid, resulting in a drastic change in the exhaust air volume in a short time. Due to hysteresis of feedback control, the laboratory is extremely prone to instantaneous negative pressure, so that unclean air in an external corridor flows back into the laboratory, and an ultra-trace analysis sample is polluted by a background environment. In addition, in order to maintain high cleanliness, the existing system generally controls all Fan Filter Units (FFUs) to be in a full-load operation state for a long time, and a dynamic adjustment mechanism aiming at actual cleanliness requirements is lacked, so that huge energy waste is caused, and the replacement period of the high-efficiency filter is shortened. Therefore, there is a need for a laboratory dust-free control system that can address the dynamic balance between exhaust safety and environmental cleanliness, and can achieve fine energy-saving management. Disclosure of Invention The invention mainly aims to provide a dust-free control system for a semiconductor ultra-trace analysis laboratory, which is used for solving the problems of lag pressure difference control and overhigh energy consumption of a fan filter unit when the ventilation hood exhaust mutation is handled in the prior art. The invention adopts the following technical scheme: The whole framework of the semiconductor ultra trace analysis laboratory dust-free control system comprises an environment sensing layer, an executing mechanism layer, a central control processing layer and an upper computer monitoring terminal. The environment sensing layer is used for collecting various environmental parameters including micro-pressure difference, temperature and humidity, suspended particle concentration and state data of the fume hood in the laboratory. The actuating mechanism layer is used for adjusting the air supply quantity, the air exhaust quantity and the cleanliness of a laboratory and mainly comprises a fan filtering unit array, a fresh air unit, an air exhaust variable air quantity valve and a water cooling unit pump set. The central control processing layer is used as a core operation unit and connected with the environment sensing layer and the execution mechanism layer, and executes control logic based on the acquired parameters. The upper computer monitoring terminal is used for providing a visual man-machine interaction interface. The central control processing layer is integrated with a pressure control module based on the integration of chemical logic and clean logic and a visual energy-saving control module of the matrix fan filter unit. The pressure control module can automatically switch between a chemical priority mode and a clean priority mode to coordinate the exhaust requirement of the fume hood and the indoor pressure difference stability, and the matrix type fan filter unit visual energy-saving control module dynamically adjusts the operation distribution model of the fan filter unit array according to the cleanliness requirement. As a preferred solution of the present invention, the pressure control module executes a feed-forward control strategy in a chemical priority mode. When the window height sensor in the environment sensing layer detects that the window height of the fume hood changes, the central control processing layer does not wait for micro-pressure difference feedback, but directly calculates the expected exhaust increment according to the product of the window opening area and the set surface wind speed, and sends an instruction for increasing the air supply quantity