WO2016090913A1

WO2016090913A1 - Online chemical liquid heating control system and method

Info

Publication number: WO2016090913A1
Application number: PCT/CN2015/083726
Authority: WO
Inventors: 马嘉; 李曼
Original assignee: 北京七星华创电子股份有限公司
Priority date: 2014-12-09
Filing date: 2015-07-10
Publication date: 2016-06-16
Also published as: CN104536365A; CN104536365B

Abstract

Disclosed are an online chemical liquid heating control system and method. According to a set temperature, by using the temperature of a heating element of a first heater (4) of a main pipeline (3) as an inner loop feedback value, the temperature of a chemical liquid at an outlet of the main pipeline (3) as an outer loop feedback value and the pressure at a chemical liquid inlet of an inlet pipeline (1) as a feed-forward value, the heating power of the first heater (4) is output, and the chemical liquid at the outlet of the main pipeline (3) is heated to the set temperature under control; and by using the temperatures of the chemical liquids at outlets of various branches (7) as feedback values, the heating powers of second heaters (8) of the various branches (7) are output respectively, and the chemical liquids at the outlets of the various branches (7) are heated under online control to target cleaning temperatures of the respective processing chamber. The influence of pipeline pressure and flow fluctuation on the temperature of the chemical liquid at the outlet of the main pipeline (3) can be effectively reduced, the uniform stability of the temperatures of the chemical liquids entering the plurality of processing chambers is ensured, the accuracy in temperature control for the chemical liquids is improved, and the time for temperature adjustment is shortened.

Description

Chemical liquid online heating control system and control method

Technical field

The present invention relates to the field of cleaning device control of semiconductor integrated circuits, and more particularly to an online heating control system and a control method for cleaning equipment chemical liquid.

technical background

Cleaning is an indispensable process in the manufacturing process of integrated circuits. The purpose of cleaning is to remove the contamination and impurities on the surface of the semiconductor wafer. Therefore, cleaning equipment is in a very important position in the field of integrated circuit equipment. In the cleaning process, the temperature of the chemical solution is a key control parameter that directly affects the cleaning results of the wafer. Deviations in the temperature of the chemical solution can cause undesirable cleaning or damage to the wafer. With the further reduction of the feature size of the fine structure on the semiconductor integrated circuit pattern wafer, it is required that the process parameters such as the temperature of the cleaning chemical liquid can be adjusted online, and the temperature control precision of the chemical liquid, the uniform stability of the temperature, and the temperature Adjustment time and the like put forward higher requirements.

For single-chip cleaning equipment with multi-process chambers, the fluctuation of the inlet pressure of the chemical liquid pipeline and the non-synchronization of the spray chemical liquid in the multi-process chamber chemical liquid supply branch will cause the main road chemical hydraulic pressure. The fluctuation of force and flow causes the deterioration of the temperature dynamic control characteristics of the main chemical liquid, which in turn affects the temperature control characteristics of the spray chemical liquid at the end of the multi-process chamber.

In addition, due to the difference in the layout and length of the chemical liquid supply branch of each process chamber, it is impossible to ensure that the chemical liquid is sprayed on the end of each process chamber only by monitoring the temperature of the chemical liquid on the main pipe of the chemical liquid supply. temperature.

Chinese Patent Publication No. CN 102218412B discloses a compounding of a cleaning liquid The temperature control method heats the chemical storage tank in the liquid recovery system by first controlling the heater, and after the temperature of the liquid in the storage tank reaches the target temperature value, the supply of the cleaning liquid is performed through the main circuit, and the heating is controlled. The heating power of the device makes the supply temperature of the main circuit stably maintain the target temperature value of the liquid supply. Although the method can make the temperature of the main circuit cleaning liquid supply outlet reach the liquid supply target temperature, when there is a multi-process chamber, since there is a certain distance between each process chamber and the main circuit heater, the chemical liquid is When the main circuit flows through the supply branches, the temperature drop will continue to occur, causing a difference between the temperature of the spray chemical liquid at the end of each process chamber and the temperature of the liquid supply outlet of the main circuit, resulting in deviation of temperature control; Since the supply branches between the process chambers and the main circuit heaters are different in length, the temperature drop of the chemical liquid flowing from the main circuit through the supply branches is also different, so that the terminal spray between the process chambers is different. There is a difference in the temperature of the leaching chemical solution, which causes the consistency of the process temperature of each process chamber to be unsuccessful, thus increasing the difficulty of temperature control. Therefore, the method disclosed in this patent can only control the outlet temperature of the chemical liquid supply main circuit, but cannot guarantee the terminal shower temperature of the chemical liquid when flowing from the main circuit to the process chambers through the respective supply branches.

In order to ensure the consistent stability of the chemical liquid temperature sprayed by the multi-process chamber under different working conditions, improve the temperature control precision of the chemical liquid, and shorten the temperature adjustment time, the present invention proposes a new chemical liquid online heating control system and Control Method.

Summary of invention

The object of the present invention is to overcome the above-mentioned drawbacks of the prior art, and to provide a chemical liquid on-line heating control system and a control method, which can effectively reduce the influence of fluctuations of pipeline pressure and flow on the temperature of the chemical liquid at the outlet of the main pipe, and ensure the entry. The uniform stability of the chemical liquid temperature of the multi-process chamber improves the temperature control accuracy of the chemical liquid and shortens the temperature adjustment time.

To achieve the above object, the present invention provides a chemical liquid on-line heating control system, the technical scheme of which is as follows:

A chemical liquid on-line heating control system for performing cleaning temperature control on a chemical liquid supply line of a semiconductor single-chip cleaning apparatus having a multi-process chamber, the supply line including an inlet line, a main line, and a plurality of parallel branches, wherein the outlets of the branches are respectively connected to the process chambers, and the method comprises:

The heater includes a first heater disposed on the main line and a second heater disposed in each of the branches, respectively for heating the chemical liquid of the main line and each of the branches;

a pressure sensor disposed in the inlet line for detecting an inlet pressure of the chemical liquid;

a temperature sensor comprising: a first temperature sensor disposed adjacent to the outlet of the main line, a second temperature sensor disposed adjacent to each of the branch outlets, and a third temperature sensor coupled to the first heater heating element, Detecting, respectively, a temperature of a chemical liquid of the main pipe outlet, each of the branch outlets, and detecting a temperature of a heating element of the first heater;

a control unit respectively connected to the pressure sensor, each of the temperature sensors, and each of the heaters, wherein the control unit passes the heating element temperature of the first heater as an inner loop feedback value according to a set temperature, Taking the chemical liquid temperature of the main pipe outlet as the outer ring feedback value and the chemical liquid inlet pressure of the inlet pipe as the feedforward value, outputting the heating power of the first heater, and controlling the main pipe exit The chemical liquid temperature is heated to a set temperature; and the heating power of each of the second heaters is respectively outputted by using the chemical liquid temperature at the outlet of each branch as a feedback value, and the outlets of the respective branches are controlled online. The chemical liquid temperature is heated to the cleaning target temperature of each of the process chambers.

Preferably, the control unit comprises:

a temperature collecting module is respectively connected to each of the temperature sensors, and converts a temperature signal from each of the temperature sensors into a digital signal and outputs the signal to a logic processing module;

An AD conversion module is coupled to the pressure sensor to convert a pressure signal from the pressure sensor into a digital signal and output the signal to a logic processing module;

The logic processing module receives and processes the temperature and pressure digital signals output by the temperature acquisition module and the AD conversion module, and the logic processing module uses the heating element temperature of the first heater as the inner loop feedback according to the set temperature The value, the chemical liquid temperature at the outlet of the main pipe is the outer ring feedback value, and the chemical liquid inlet pressure of the inlet pipe is the feedforward value, and the heating power of the first heater is calculated, and the The chemical liquid temperature at the branch outlet is a feedback value, and the heating power of each of the second heaters is calculated and output to the analog output module respectively;

An analog output module, converting the heating power output by the logic processing module into a voltage or current signal, controlling the first heater to heat the chemical liquid temperature of the main line outlet to a set temperature, and controlling each place online The second heater heats the chemical liquid temperature of each of the branch outlets to a cleaning target temperature of each of the process chambers.

Preferably, the control unit is a PLC programmable controller, an MCU embedded controller or a computer.

Preferably, the method further includes a normally open small flow return line, the inlet of the return line is connected in parallel with each of the branches to the outlet of the main line, and the outlet of the return line leads to the chemical liquid recovery unit Wherein the chemical liquid of the main line is kept in a flowing state by the normally open of the return line, and, when each of the branches is closed, the control unit continues to pass the first according to the set temperature The heating element temperature of a heater is an inner loop feedback value, and the chemical liquid at the outlet of the main pipe The temperature is an outer loop feedback value, and the chemical liquid inlet pressure of the inlet line is a feedforward value, and the heating power of the first heater is calculated, and the chemical liquid temperature at the outlet of the main pipe is controlled to be maintained at a set value. temperature.

Preferably, the diameter of the return line is smaller than the diameter of the main line.

Preferably, the return line is provided with a flow control valve, and the flow control valve controls the flow rate of the return line to be smaller than the process flow of the main line when each of the branches is opened.

Preferably, the flow control valve is a manual flow regulating valve or an electro-hydraulic flow control valve.

Preferably, the heating element of the first heater is an electric heating wire, and the third temperature sensor is connected to an electric heating wire of the first heater.

Preferably, the inlet pipe before the pressure sensor, the main pipe outlet after the first temperature sensor, and the inlet and the outlet of each of the branches are respectively provided with control valves.

Preferably, the inlet pipe is sequentially provided with a manual control valve and a pressure regulating valve, and the main pipe outlet, each of the branch inlets and the outlets are respectively provided with pneumatic control valves; wherein each of the branch outlets is pneumatically The control valve is used to control the spraying of chemical liquid.

In order to achieve the object of the present invention, the present invention also provides a chemical liquid on-line heating control method, the technical scheme of which is as follows:

A chemical liquid on-line heating control method adopts the above chemical liquid on-line heating control system for performing cleaning temperature control on a chemical liquid supply line of a semiconductor single-chip cleaning device having a multi-process chamber, the supply line including An inlet pipe, a main pipe, and a plurality of parallel branches are connected in sequence, and the outlets of the branches are respectively connected to the process chambers, and the method includes:

Step S01: introducing a cleaning chemical liquid to the inlet pipe and the main pipe of the supply pipeline, and opening a first heater provided on the main pipe to heat the chemical liquid of the main pipe;

Step S02: According to the set temperature, the heating element temperature of the first heater is an inner loop feedback value, the chemical liquid temperature of the main line outlet is an outer loop feedback value, and the chemistry of the inlet pipeline is The liquid inlet pressure is a feedforward value, and the heating power of the first heater is calculated by a control algorithm, and the chemical liquid temperature of the main pipe outlet is controlled to be heated to a set temperature;

Step S03: introducing a cleaning chemical liquid to each of the parallel branches connected to the main line, and opening a second heater respectively provided in each of the branches to heat the chemical liquid of each of the branches;

Step S04: According to the set temperature, the chemical liquid temperature of each branch outlet is used as a feedback value, and the heating power of each of the second heaters is separately calculated by a control algorithm, and the outlets of the branches are controlled online. The temperature of the chemical liquid is heated to the cleaning target temperature of the respective process chamber;

Step S05: performing a cleaning process by introducing chemical liquid into each of the process chambers, and repeating steps S02 and S04 to stably maintain the temperature of the chemical liquid at the outlet of each branch at the cleaning target temperature of each of the process chambers. .

Preferably, while waiting to pass the chemical liquid into each of the process chambers, each of the branches is closed, the chemical liquid of the main line is in a flowing state, and then, step S02 is continued to make the first heating The device still maintains a certain heating power, and controls the temperature of the chemical liquid at the outlet of the main pipe to be maintained at a set temperature, so as to shorten the temperature of the chemical liquid at the outlet of each branch when switching from the waiting state to the cleaning process state. The adjustment time required to reach the target temperature for cleaning.

Preferably, the chemical liquid of the main line is in a flowing state by: connecting a normally open small flow return line in parallel at the outlet of the main line, and when the branches are closed, the main pipe is made The chemical liquid of the road continues to flow out through the return line.

Preferably, the flow rate of the chemical liquid in the return line is smaller than the flow rate of the chemical liquid in the main line in the cleaning process state.

Preferably, the method for making the chemical liquid flow rate in the return line smaller than the chemical liquid flow rate in the main line in the cleaning process state is: processing the pipe diameter of the return line to be smaller than the pipe diameter of the main pipe.

Preferably, the method for making the chemical liquid flow in the return line smaller than the chemical liquid flow in the main line in the cleaning process state is: providing a flow control valve in the return line, and adjusting the flow control valve by adjusting The opening degree is controlled to control the flow rate of the chemical liquid in the return line to be smaller than the flow rate of the main line in the cleaning process state.

It can be seen from the above technical solutions that the beneficial effects of the present invention are as follows:

1) By detecting the fluctuation of the inlet pressure of the chemical liquid by setting the pressure sensor in the chemical liquid inlet pipe, and using the detected value for the feedforward of the temperature control, the pressure fluctuation of the chemical liquid inlet pipe and the multi-path parallel can be effectively reduced. The influence of fluctuations in the pressure and flow rate of the chemical liquid main pipe caused by the opening and closing of the chemical liquid supply branch to the chemical liquid temperature at the outlet of the chemical liquid supply pipe.

2) By using the temperature of the heating element of the first heater for detecting the chemical liquid as the inner loop feedback value, and detecting the chemical liquid temperature of the outlet of the chemical liquid supply as the outer loop feedback value, the chemical liquid on-line heating control system can be effectively shortened. The temperature adjustment time increases the temperature control accuracy.

3) By using the second temperature sensor and the second heater disposed on the multi-parallel chemical liquid supply branch, the temperature of the chemical liquid at each branch outlet is detected as a feedback value, which can effectively ensure the multi-process chamber in different working conditions. The temperature of the sprayed chemical liquid can be adjusted online and can improve the consistent stability of the spray chemical temperature.

4) By setting a return line with a small flow rate, the adjustment required to control the temperature of the chemical liquid to reach the target temperature of each process chamber can be effectively shortened when the online heating control system switches from the idle state waiting for the liquid supply to the cleaning process state. time.

DRAWINGS

1 is a schematic structural view of a preferred embodiment of a chemical liquid on-line heating control system of the present invention;

2 is a block diagram showing the control principle of the first heater of the chemical liquid online heating control system of the present invention;

3 is a block diagram showing the control principle of the second heater of the chemical liquid online heating control system of the present invention;

4 is a flow chart of a preferred embodiment of the chemical liquid on-line heating control method of the present invention.

Summary of the invention

The specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

In the following specific embodiments of the present invention, a chemical liquid on-line heating control system of the present invention and a chemical liquid on-line heating control method using the same are described in detail. The invention relates to a chemical liquid on-line heating control system and a control method for performing cleaning temperature control on a chemical liquid supply line of a semiconductor single-chip cleaning device having a multi-process chamber.

In a specific embodiment of the present invention, please refer to FIG. 1. FIG. 1 is a schematic structural view of a preferred embodiment of a chemical liquid on-line heating control system of the present invention. As shown in Fig. 1, in the chemical liquid on-line heating control system of the present invention, the inlet line 1, the main line 3 and the three-way parallel branch 7 are sequentially connected to form a supply line. The number of branches 7 can be configured in accordance with the needs of the equipment and the process. The figure exemplifies the case when there are three parallel branches 7. The inlet of the three-way branch 7 is connected in parallel to the outlet of the main line 3. The outlets of each of the branches 7 are connected to respective process chambers (not shown).

Please continue to refer to Figure 1. The main line 3 in the supply line is provided with a first heater 4 for heating the chemical liquid flowing from the inlet line 1 and flowing through the main line 3; meanwhile, in the illustrated three way branch 7 respectively A second heater 8 is provided for heating the chemical liquid flowing from the main line 3 and flowing through each branch 7. In order to reduce the heat loss of the heated chemical liquid in the subsequent pipeline, first, first The two

heaters

4, 8 can be installed at the outlets close to the main line 3 and each branch 7, respectively.

Please continue to refer to Figure 1. A pressure sensor (PT) 2 is installed in the inlet line 1 for detecting the inlet pressure of the chemical liquid. In the cleaning process, the chemical liquid in the inlet pipe 1 will generate pressure fluctuations, and the opening and closing of each branch 7 will also cause fluctuations in the chemical liquid pressure and flow rate in the main pipe 3, and these fluctuations will be at the exit of the main pipe 3 The temperature of the chemical liquid has an effect. Therefore, the present invention can immediately detect the pressure fluctuation of the chemical liquid of the main line 3 by the pressure sensor 2 installed at the inlet line 1, and use the detected value for the feedforward of the heating temperature control.

Please continue to refer to Figure 1. The heating control system of the present invention further includes temperature sensors corresponding to the first and

second heaters

4, 8, respectively, and specifically includes a first temperature sensor (TS) 6 installed after the first heater 4 and near the exit of the main line 3. Installed in a second temperature sensor (TS) 9 located after the second heater 8 near the outlet of each branch 7, and a third temperature sensor (TS) 5 connecting the heating elements of the first heater 4, respectively The temperature of the chemical liquid at the outlet of the main pipe 3 and the outlet of each branch 7 is detected, and the temperature of the heating element of the first heater 4 is detected. The first and

second heaters

4, 8 may be selected such that the heating element is a heater in the form of an electric heating wire, so that the third temperature sensor 5 is directly connected to the electric heating wire of the first heater 4 to more accurately detect the first The heating wire temperature of a heater 4.

The invention controls the temperature of the chemical liquid in the liquid supply line through the set control unit. The control unit is respectively connected to the pressure sensor 2, the

temperature sensors

6, 9, 5 and the heaters 4, 8 (the control unit and its connection with the pressure sensor 2, the

temperature sensors

6, 9, 5 and the heater 4 are omitted from the illustration, 8 connection status). The control unit includes a temperature acquisition module, an AD conversion module, a logic processing module, and an analog output module. The configuration and working relationship between the modules of the control unit can be further illustrated by FIG. 2 and FIG. 3, respectively.

Please refer to FIG. 2, which is a block diagram of the control principle of the first heater of the chemical liquid on-line heating control system of the present invention, which shows that the control unit realizes the exit of the main line 3 by controlling the first heater. Control of the temperature of the chemical liquid outlet. As shown in FIG. 2, the temperature collecting module of the control unit is respectively connected to the first and third temperature sensors 6, 5, and converts the collected temperature signals from the temperature sensors 6, 5 into digital signals, and outputs them to the logic processing module. . The AD conversion module is connected to the pressure sensor 2, converts the collected pressure signal from the pressure sensor 2 into a digital signal, and outputs it to the logic processing module. After the logic processing module receives the temperature and pressure digital signals output by the temperature acquisition module and the AD conversion module, the processing starts. The logic processing module measures the temperature of the heating element of the first heater 4 according to the set temperature T1 of the outlet chemical liquid to the main line 3 (ie, the temperature of the first heater 4 electric heating wire detected by the third temperature sensor 5) T The heating wire is an inner ring control feedback value, and the detection temperature of the chemical liquid at the outlet of the main pipe 3 (ie, the temperature of the chemical liquid at the outlet of the main pipe 3 detected by the first temperature sensor 6) T is the outer loop control feedback value, and The chemical liquid inlet detecting pressure of the inlet line 1 (ie, the pressure of the chemical liquid of the inlet line 1 detected by the pressure sensor 2) P1 is a feedforward (compensation) control value, and the first heater 4 is calculated by a certain control algorithm. The power is heated and this calculated value is output to the analog output module. The analog output module converts the heating power outputted by the logic processing module into a voltage or current signal, and outputs the signal to the controller of the first heater 4, so that the first heater 4 operates at the power, and the chemical liquid in the main line 3 is performed. heating. Thereby, the control unit can control the first heater 4 to heat the temperature of the chemical liquid at the outlet of the main line 3 to the set temperature T1.

Referring to FIG. 3 again, FIG. 3 is a block diagram of a control principle of a second heater of a chemical liquid on-line heating control system according to the present invention, which shows that the control unit controls the heating of the first heater 4, and simultaneously passes the The second heater 8 is controlled to finally realize the chemical liquid at the exit of each branch 7 The outlet temperature is controlled online. As shown in FIG. 3, the temperature collecting module of the control unit is further connected to the second temperature sensor 9 installed in each branch 7, respectively, and the collected temperature signals from the respective second temperature sensors 9 are converted into digital signals and output to the logic. Processing module. After the control unit controls the first heater 4 to heat the temperature of the chemical liquid at the outlet of the main line 3 to the set temperature T1, the branch control is started, and the branch of each branch 7 outputted by the temperature collecting module is continuously received by the logic processing module. The chemical liquid exits the temperature digital signal and is processed. The logic processing module sets the temperature T2 according to the chemical liquid process at the outlet of each branch 7, and measures the temperature at the outlet of each branch 7 (i.e., the chemistry at the exit of each branch 7 detected by the second temperature sensor 9). The liquid temperature) T branch is a feedback value, and the heating power of each second heater 8 is calculated by a certain control algorithm, and these calculated values are output to the analog output module. The analog output module converts the heating power of each second heater 8 output by the logic processing module into a voltage or current signal, and outputs the signals to the controllers of the corresponding second heaters 8, respectively, so that the second heaters 8 are correspondingly The power command operates to heat the chemical liquid in each branch 7. Therefore, the control unit can control the first heater 4 to heat the chemical liquid in the main line 3 to the set temperature T1, and further control each of the second heaters 8 to control the branches during the cleaning process. The chemical liquid temperature at the outlet 7 is separately heated to the temperature T2 required by the chemical liquid cleaning process of the respective process chamber, and a complete heating temperature control cycle of the chemical liquid online heating control system of the present invention is completed.

Thereafter, the chemical liquid on-line heating control system of the present invention will continue to adjust the first heating in a periodic inner and outer ring temperature control mode, supplemented by pressure feedforward compensation, in accordance with the above mode during the cleaning process. The power of the device 4 is such that the temperature of the chemical liquid outlet in the main line 3 is maintained at the set temperature T1; and the power of the second heater 8 is immediately adjusted according to the outlet temperature of the chemical liquid in the main line 3, so that each branch 7 is The temperature of the chemical liquid outlet is maintained at the temperature required by the respective process Degree T2, the online control function of the heating control system of the present invention is implemented.

Preferably, the control unit can be a PLC programmable controller, an MCU embedded controller or a computer.

Please continue to refer to Figure 1. A normally open small flow return line 10 is also connected to the outlet of the main line 3, and the inlet of the return line 10 is connected in parallel with each branch 7 to the outlet of the main line 3, and the outlet of the return line 10 leads to the chemical liquid Recycling unit. By bringing the return line 10 into the normally open state, when the respective branches 7 are closed, the chemical liquid of the main line 3 enters the chemical liquid recovery unit through the return line 10, so that the chemical liquid of the main line 3 can be kept in a flowing state. One function of the return line 10 is to wait for the chemical liquid to pass into each process chamber, for example, when the branches 7 have not been opened before the cleaning process, or between the batches of the product. When the abnormality in the cleaning process or the shutdown of each branch 7 and other conditions in which the branches 7 need to be closed occurs, the chemical liquid of the main line 3 is still in a flowing state. The purpose is to control the temperature of the chemical liquid at the outlet of the main line 3 to be maintained by keeping the chemical liquid of the main line 3 in a flowing state when the branches 7 are closed, and maintaining the first heater 4 with a certain heating power. The temperature T1 is set to shorten the adjustment time required to control the temperature of the chemical liquid at the outlet of each branch 7 to reach the cleaning target temperature T2 when switching from the waiting state to the cleaning process state.

When each branch 7 is closed, the chemical liquid of the main line 3 will enter the chemical liquid recovery unit through the return line 10, so that the chemical liquid of the main line 3 remains in a flowing state. The control unit continues to pass the heating wire temperature T of the first heater 4 as the inner ring feedback value according to the set temperature T1, and the chemical liquid temperature T of the main pipe 3 outlet is the outer ring feedback value, and the inlet pipe is used as the inlet pipe. The chemical liquid inlet pressure P1 of the road 1 is a feedforward value, and the heating power of the first heater 4 is calculated, and the temperature of the chemical liquid at the outlet of the main pipe 3 is controlled to be maintained and maintained at the set temperature T1. Due to the chemical liquid temperature at the exit of main line 3 The degree is always maintained at the set temperature T1, and therefore, the adjustment time when the temperature of the chemical liquid at the outlet of each branch 7 is heated to the cleaning target temperature of the respective process chamber is significantly shortened, so that the process efficiency is remarkably improved.

Preferably, the diameter of the return line 10 is processed to be smaller than the diameter of the main line 3, so that the flow rate of the main line 3 can be reduced by setting a small flow rate return line 10, so that the heating power of the first heater 4 It can be maintained at a lower state to reduce the thermal budget of the cleaning process and save costs. It is also possible to install the flow control valve 13 in the return line 10, and to control the flow control valve 13 to have a certain opening degree, so that the flow rate of the return line 10 is smaller than the normal process flow of the main line 3 when each branch 7 is opened, and the waiting is realized. When the main line 3 maintains a small flow. Further preferably, the flow control valve 13 is a manual flow regulating valve or an electro-hydraulic flow control valve, which enables precise adjustment of the flow rate of the return line 10, thereby controlling the main line 3 to maintain a small flow rate.

Please continue to refer to Figure 1. On the basis of the above heating control system, in order to better control the opening and closing of the liquid supply pipeline, control valves are respectively installed in the inlet pipeline 1, the main pipeline 3 and each branch 7, and specifically include: a pressure sensor The inlet pipe 1 before 2 is sequentially equipped with a manual control valve 16 and a pressure regulating valve 11, and the manual control valve 16 controls the opening and closing of the inlet pipe 1, and the pressure regulating valve 11 is provided to be in accordance with the opening and closing of each branch 7 When the pressure and flow of the road 3 fluctuate, the pressure of the inlet pipe 1 is stabilized to a certain range, so as to reduce the pressure fluctuation of the inlet pipe 1 and the fluctuation of the pressure and flow of the main pipe 3 caused by the opening and closing of each branch 7 to the chemical liquid supply. The influence of the temperature of the chemical liquid at the outlet of the main pipeline 3; the main pipe 3 after the first temperature sensor 6, and the inlet of each branch 7 are equipped with

pneumatic control valves

12, 14 to facilitate the quick opening of the main pipe 3 and the branches 7 In addition, a pneumatic control valve 15 for controlling the chemical liquid spray is separately installed at the outlet of each branch 7 to control and adjust the form of the chemical liquid entering each process chamber.

Taking the application of each of the above control valves in an operating state of the liquid supply line as an example, when the

pneumatic control valves

14 and 15 of each branch 7 are closed, the manual control valve 16 of the inlet line 1 and the main line 3 are opened. When the pneumatic control valve 12 and the flow control valve 13 of the return line 10 are adjusted, the chemical liquid is regulated by the external pressure from the inlet line 1 through the pressure regulating valve 11 to a certain range, and passes through the first After heating, the heater 4 flows to the outlet of the chemical liquid supply main pipe 3, and then flows out through the small flow return line 10. After the control unit controls the first heater 4 to heat the temperature of the chemical liquid at the outlet of the main line 3 to a set temperature, the

pneumatic control valves

14, 15 on any one or several of the parallel parallel chemical liquid supply branches 7 are opened, the main controller A part of the chemical liquid in the road 3 will flow into the branch 7 or a plurality of branches 7, and after the control unit controls the second heater 8 to heat the temperature of the chemical liquid at the outlet of the branch 7 to the process temperature corresponding to the process chamber, the flow The process chamber is used to clean the wafer.

A chemical liquid on-line heating control method of the present invention will be described in detail with reference to FIG. 4 is a flow chart of a chemical liquid on-line heating control method according to the present invention, wherein the chemical liquid on-line heating control method uses the above chemical liquid on-line heating control system for semiconductor single-chip cleaning with a multi-process chamber The chemical liquid supply line of the device performs cleaning temperature control, and the supply line includes an inlet pipe, a main pipe and a plurality of parallel branches which are sequentially connected, and the outlets of the branches are respectively connected to the process chambers. The method can be understood simultaneously with reference to FIG. As shown in FIG. 4, the chemical liquid on-line heating control method of the present invention comprises the following steps:

As shown in block S01, step S01: the cleaning chemical liquid is introduced into the inlet pipe and the main pipe of the supply line, and the first heater provided in the main pipe is opened to heat the chemical liquid of the main pipe.

As shown in block S02, step S02: according to the set temperature, the heating element temperature of the first heater is the inner loop feedback value, the chemical liquid temperature of the main line outlet is the outer loop feedback value, and the chemistry of the inlet line is used. The liquid inlet pressure is a feedforward value, and the heating work of the first heater is calculated by a control algorithm. Rate, control to heat the temperature of the chemical liquid at the main line outlet to the set temperature.

As shown in block S03, step S03: the cleaning chemical liquid is supplied to each of the parallel branches connected to the main line, and the second heaters respectively provided in the respective branches are opened to heat the chemical liquid of each branch.

As shown in block S04, step S04: according to the set temperature, the chemical liquid temperature at each branch outlet is used as a feedback value, and the heating power of each second heater is separately calculated by a control algorithm, and the outlets of the respective branches are controlled online. The chemical liquid temperature is heated to the cleaning target temperature of the respective process chamber.

As shown in block S05, step S05: performing a cleaning process by introducing chemical liquid into each process chamber, and repeating steps S02 and S04, so that the temperature of the chemical liquid at each branch outlet is stably maintained at the cleaning target temperature of the respective process chambers. .

The above control of the heating temperature can be controlled by the control unit of the chemical liquid online heating control system.

Further, in the case of employing the above-described method of the present invention, if it is necessary to wait for the chemical liquid to be introduced into each process chamber, the branches are closed and the chemical liquid of the main line is still in a flowing state. Then, proceeding to step S02, the first heater still maintains a certain heating power, and controls the temperature of the chemical liquid at the outlet of the main pipe to be maintained at the set temperature, so as to shorten the control when switching from the waiting state to the cleaning process state. The adjustment time required for the chemical liquid temperature at the branch outlet to reach the target temperature for cleaning.

In order to make the chemical liquid of the main line flow, a normally open small flow return line can be connected in parallel at the outlet of the main line (refer to Figure 1), and the chemical liquid of the main line is made when each branch is closed. Continuous flow through the return line. In order to reduce the thermal budget of the cleaning process and save costs, it is necessary to make the flow rate of the chemical liquid in the return line smaller than the flow rate of the chemical liquid in the main line in the cleaning process state. The method can adopt the method of processing the diameter of the return line to be smaller than the diameter of the main line, so that the small flow can be The amount of return line reduces the flow of the main line so that the heating power of the first heater can be maintained at a lower state. It is also possible to install a flow control valve in the return line, and by controlling the opening degree of the flow control valve, the flow rate of the return line is smaller than the normal process flow when the main line is in the cleaning process state when each branch is opened, and the supervisor is made to wait while waiting. The road maintains a small flow rate so that the heating power of the first heater can be maintained at a lower state.

In summary, compared with the prior art, the present invention can effectively reduce the chemical liquid by setting a pressure sensor in the chemical liquid inlet pipe to detect the inlet pressure fluctuation of the chemical liquid and using the detected value for the feedforward of the temperature control. The fluctuation of the inlet line pressure and the fluctuation of the pressure and flow of the main flow path of the chemical liquid caused by the opening and closing of the chemical liquid supply branch in parallel; the influence of the chemical liquid temperature on the outlet of the chemical liquid supply pipe; The temperature of the heating element (ie, heating wire) of a heater is used as the feedback value of the inner ring, and the temperature of the chemical liquid supplied to the outlet of the main pipe is used as the feedback value of the outer ring, which can effectively shorten the temperature adjustment time of the chemical liquid online heating control system and improve the temperature. Temperature control accuracy; by using the second temperature sensor and the second heater disposed on the multi-parallel chemical liquid supply branch, the temperature of the chemical liquid at the outlet of each branch is used as a feedback value, which can effectively ensure that the multi-process chamber is different The temperature of the chemical liquid sprayed under working conditions can be adjusted online and can improve the uniform stability of the temperature of the spray chemical solution. When provided by a return line having a small flow rate, can shorten the heating control system is switched from the line waiting for the idle state to the liquid state of the cleaning process, the temperature control of chemical liquid cleaning process chamber of achieving the target temperature required for adjusting the time.

The above are only the preferred embodiments of the present invention, and the embodiments are not intended to limit the scope of the patent protection of the present invention. Therefore, equivalent structural changes made by using the description of the present invention and the contents of the drawings should be included in the same manner. Within the scope of protection of the present invention.

Claims

A chemical liquid on-line heating control system for performing cleaning temperature control on a chemical liquid supply line of a semiconductor single-chip cleaning apparatus having a multi-process chamber, the supply line including an inlet line, a main line, and a plurality of parallel branches, wherein the outlets of the branches are respectively connected to the process chambers, and the method comprises:

The heater includes a first heater disposed on the main line and a second heater disposed in each of the branches, respectively for heating the chemical liquid of the main line and each of the branches;

a pressure sensor disposed in the inlet line for detecting an inlet pressure of the chemical liquid;

a temperature sensor comprising: a first temperature sensor disposed adjacent to the outlet of the main line, a second temperature sensor disposed adjacent to each of the branch outlets, and a third temperature sensor coupled to the first heater heating element, Detecting, respectively, a temperature of a chemical liquid of the main pipe outlet, each of the branch outlets, and detecting a temperature of a heating element of the first heater;

a control unit respectively connected to the pressure sensor, each of the temperature sensors, and each of the heaters, wherein the control unit passes the heating element temperature of the first heater as an inner loop feedback value according to a set temperature, Taking the chemical liquid temperature of the main pipe outlet as the outer ring feedback value and the chemical liquid inlet pressure of the inlet pipe as the feedforward value, outputting the heating power of the first heater, and controlling the main pipe exit The chemical liquid temperature is heated to a set temperature; and the heating power of each of the second heaters is respectively outputted by using the chemical liquid temperature at the outlet of each branch as a feedback value, and the outlets of the respective branches are controlled online. The chemical liquid temperature is heated to the cleaning target temperature of each of the process chambers.
The chemical liquid online heating control system according to claim 1, wherein the control unit comprises:

a temperature collecting module is respectively connected to each of the temperature sensors, and converts a temperature signal from each of the temperature sensors into a digital signal and outputs the signal to a logic processing module;

An AD conversion module coupled to the pressure sensor to apply pressure from the pressure sensor Converting the signal to a digital signal and outputting it to the logic processing module;

The logic processing module receives and processes the temperature and pressure digital signals output by the temperature acquisition module and the AD conversion module, and the logic processing module uses the heating element temperature of the first heater as the inner loop feedback according to the set temperature The value, the chemical liquid temperature at the outlet of the main pipe is the outer ring feedback value, and the chemical liquid inlet pressure of the inlet pipe is the feedforward value, and the heating power of the first heater is calculated, and the The chemical liquid temperature at the branch outlet is a feedback value, and the heating power of each of the second heaters is calculated and output to the analog output module respectively;

An analog output module, converting the heating power output by the logic processing module into a voltage or current signal, controlling the first heater to heat the chemical liquid temperature of the main line outlet to a set temperature, and controlling each place online The second heater heats the chemical liquid temperature of each of the branch outlets to a cleaning target temperature of each of the process chambers.
The chemical liquid online heating control system according to claim 1 or 2, wherein the control unit is a PLC programmable controller, an MCU embedded controller or a computer.
The chemical liquid online heating control system according to claim 1 or 2, further comprising a normally open small flow return line, the inlet of the return line being connected in parallel with each of the branches to the main pipe An outlet of the return line, the outlet of the return line leading to the chemical liquid recovery unit; wherein the chemical liquid of the main line is kept in a flowing state by the normally open of the return line, and is closed in each of the branches The control unit continues to pass the heating element temperature of the first heater as an inner loop feedback value, the chemical liquid temperature of the main line outlet as an outer loop feedback value, and the inlet according to the set temperature. The chemical liquid inlet pressure of the pipeline is a feedforward value, and the heating power of the first heater is calculated to control the temperature of the chemical liquid at the outlet of the main pipe to be maintained at a set temperature.
The chemical liquid online heating control system according to claim 4, wherein the diameter of the return line is smaller than the diameter of the main line.
The chemical liquid online heating control system according to claim 4, wherein the return line is provided with a flow control valve, and the flow control valve controls the flow rate of the return line to be smaller than the main line at each station The process flow when the branch is opened.
The chemical liquid online heating control system according to claim 6, wherein The flow control valve is a manual flow regulating valve or an electro-hydraulic flow control valve.
The chemical liquid on-line heating control system according to claim 1, wherein the heating element of the first heater is an electric heating wire, and the third temperature sensor is connected to an electric heating wire of the first heater.
The chemical liquid online heating control system according to claim 1, wherein said inlet line before said pressure sensor, said main line exit after said first temperature sensor, and said branch of said branch Control valves are provided at the inlet and outlet respectively.
The chemical liquid online heating control system according to claim 9, wherein the inlet pipe is sequentially provided with a manual control valve and a pressure regulating valve, and the main pipe outlet, each branch inlet and outlet are respectively provided There is a pneumatic control valve; wherein the pneumatic control valve of each branch outlet is used to control the spraying of the chemical liquid.
A chemical liquid on-line heating control method using the chemical liquid on-line heating control system according to any one of claims 1 to 10 for cleaning a chemical liquid supply line of a semiconductor single-chip cleaning device having a multi-process chamber The temperature control, the supply line includes an inlet pipe, a main pipe, and a plurality of parallel branches, and the outlets of the branches are respectively connected to the process chambers, and the method includes:

Step S01: introducing a cleaning chemical liquid to the inlet pipe and the main pipe of the supply pipeline, and opening a first heater provided on the main pipe to heat the chemical liquid of the main pipe;

Step S02: According to the set temperature, the heating element temperature of the first heater is an inner loop feedback value, the chemical liquid temperature of the main line outlet is an outer loop feedback value, and the chemistry of the inlet pipeline is The liquid inlet pressure is a feedforward value, and the heating power of the first heater is calculated by a control algorithm, and the chemical liquid temperature of the main pipe outlet is controlled to be heated to a set temperature;

Step S03: introducing a cleaning chemical liquid to each of the parallel branches connected to the main line, and opening a second heater respectively provided in each of the branches to heat the chemical liquid of each of the branches;

Step S04: According to the set temperature, the chemical liquid temperature of each branch outlet is used as a feedback value, and the heating power of each of the second heaters is separately calculated by a control algorithm, and the outlets of the branches are controlled online. The temperature of the chemical liquid is heated to the cleaning target temperature of the respective process chamber;

Step S05: performing a cleaning process by introducing chemical liquid into each of the process chambers, and repeating steps S02 and S04 to stably maintain the temperature of the chemical liquid at the outlet of each branch at the cleaning target temperature of each of the process chambers. .
The chemical liquid on-line heating control method according to claim 11, wherein each of said branches is closed while waiting for a chemical liquid to be introduced into each of said process chambers, so that the chemical liquid of said main line is in a flow State, then proceeding to step S02, so that the first heater still maintains a certain heating power, and controls the temperature of the chemical liquid at the main line outlet to be maintained at a set temperature to shorten the switching from the waiting state to the cleaning process In the state, the adjustment time required for the chemical liquid temperature at each of the branch outlets to reach the cleaning target temperature is controlled again.
The chemical liquid on-line heating control method according to claim 12, wherein the chemical liquid of the main line is in a flowing state by: connecting a normally open small flow return pipe in parallel at the outlet of the main pipe; And, when each of the branches is closed, the chemical liquid of the main line is continuously discharged through the return line.
The chemical liquid on-line heating control method according to claim 13, wherein the flow rate of the chemical liquid in the return line is smaller than the flow rate of the chemical liquid in the main line in the cleaning process state.
The method for controlling the on-line heating of a chemical liquid according to claim 14, wherein the method for making the chemical liquid flow rate in the return line smaller than the chemical flow rate in the main line in the cleaning process state is: The pipe diameter of the road is processed to be smaller than the pipe diameter of the main pipe.
The method for controlling the on-line heating of a chemical liquid according to claim 14, wherein the method for making the chemical liquid flow rate in the return line smaller than the state of the chemical liquid in the main line in the cleaning process state is: in the return pipe The flow rate control valve is disposed, and the flow rate of the chemical liquid in the return line is controlled to be smaller than the flow rate of the main line in the cleaning process state by adjusting the opening degree of the flow control valve.