WO2020006956A1 - 一种防真空泵管路堵塞的方法及化学气相镀膜机 - Google Patents

一种防真空泵管路堵塞的方法及化学气相镀膜机 Download PDF

Info

Publication number
WO2020006956A1
WO2020006956A1 PCT/CN2018/115304 CN2018115304W WO2020006956A1 WO 2020006956 A1 WO2020006956 A1 WO 2020006956A1 CN 2018115304 W CN2018115304 W CN 2018115304W WO 2020006956 A1 WO2020006956 A1 WO 2020006956A1
Authority
WO
WIPO (PCT)
Prior art keywords
vacuum pump
exhaust pipe
chemical vapor
pipe
exhaust
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2018/115304
Other languages
English (en)
French (fr)
Inventor
单剑锋
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
HKC Co Ltd
Original Assignee
HKC Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by HKC Co Ltd filed Critical HKC Co Ltd
Priority to US16/316,348 priority Critical patent/US11028475B2/en
Publication of WO2020006956A1 publication Critical patent/WO2020006956A1/zh
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/4412—Details relating to the exhausts, e.g. pumps, filters, scrubbers, particle traps
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/4401—Means for minimising impurities, e.g. dust, moisture or residual gas, in the reaction chamber
    • C23C16/4404—Coatings or surface treatment on the inside of the reaction chamber or on parts thereof
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/4401—Means for minimising impurities, e.g. dust, moisture or residual gas, in the reaction chamber
    • C23C16/4408—Means for minimising impurities, e.g. dust, moisture or residual gas, in the reaction chamber by purging residual gases from the reaction chamber or gas lines
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
    • Y02C20/00—Capture or disposal of greenhouse gases
    • Y02C20/30—Capture or disposal of greenhouse gases of perfluorocarbons [PFC], hydrofluorocarbons [HFC] or sulfur hexafluoride [SF6]

Definitions

  • the present application relates to the technical field of chemical vapor deposition coating equipment, in particular to a method for preventing clogging of a vacuum pump pipeline and a chemical vapor coating machine.
  • Chemical vapor deposition machine is also called vacuum coating machine, which mainly refers to a type of coating that needs to be performed under a high degree of vacuum. It includes many types, including vacuum ion evaporation, magnetron sputtering, MBE molecular beam epitaxy, and PLD laser sputtering. There are many kinds of deposition.
  • the chemical vapor deposition machine produces a chemical reaction during the coating process, and a reactant powder is generated during the chemical reaction.
  • the powder generated after the reaction is discharged from the vacuum pump with the self-made process chamber in the system. Changes in the temperature, pressure, and air extraction efficiency of the circuit cause the powder on the inner wall of the vacuum pump's pipeline to increase in probability, and cause the pipeline to adhere and block. This powder blocking phenomenon will cause the exhaust of the vacuum pump to be unsmooth, and the cavity equipment for the coating process cannot be controlled to stop the pressure.
  • the clogging of the inner wall of the vacuum pump pipeline requires the process room to be shut down.
  • the maintenance staff disassembles the outlet pipe of the vacuum pump and cleans the pipeline by water washing. In the 20th, production efficiency and equipment utilization rate are reduced, meanwhile, maintenance expenses are increased, and production costs are increased.
  • the purpose of this application is to propose a method for preventing the vacuum pump pipeline from being blocked, so as to effectively improve the phenomenon of powder adhesion and clogging in the vacuum pump pipeline.
  • a method for preventing the vacuum pump pipeline from being blocked includes the following steps:
  • the gas source is closed, and a heated inert gas is passed into the exhaust pipe connected to the air outlet of the vacuum pump;
  • the vacuum pump is turned on, and the dust and exhaust gas in the process chamber pass into the exhaust gas treatment device through the exhaust pipe.
  • the exhaust pipe is insulated.
  • the air inlet pipe connected to the air inlet of the vacuum pump is heated after coating and before the vacuum pump is turned on.
  • the inner wall of the exhaust pipe is plated with a coating layer for preventing dust from adhering to reduce the probability of powder adhesion on the inner wall of the exhaust pipe.
  • the present application also provides a chemical vapor coating machine using the method for preventing the vacuum pump pipeline from being blocked, so as to reduce the probability of powder adhesion on the vacuum pump pipeline during the chemical vapor coating process.
  • a chemical vapor coating machine applying the above-mentioned method of preventing the vacuum pump pipeline from being blocked, a vacuum pump, a process chamber and an exhaust gas treatment device, an air inlet pipe is connected between the vacuum pump and the process chamber, the exhaust gas treatment device and the vacuum pump An exhaust pipe is connected between the exhaust pipe, and an inflation pipe is connected to an end of the exhaust pipe near the vacuum pump.
  • the inflation pipe is used to fill the exhaust pipe with an inert gas, and the inflation pipe is provided with a first heating equipment.
  • the exhaust pipe is provided with a thermal insulation device.
  • it further includes a second heating device provided at the end of the intake pipe near the vacuum pump and / or a third heating device of the exhaust pipe near the vacuum pump.
  • At least the inner wall of the air inlet of the exhaust pipe is plated with a coating layer to prevent dust from adhering.
  • the anti-dust adhesion coating layer is a polytetrafluoroethylene layer.
  • the present application provides a chemical vapor coating machine, including a vacuum pump, a process chamber, and an exhaust gas treatment device.
  • An air inlet pipe is connected between the vacuum pump and the process chamber, the exhaust gas treatment device, and
  • An exhaust pipe is connected between the vacuum pumps, and further includes:
  • a coating layer is provided on the inner side wall of the intake pipe and the exhaust pipe to prevent dust from adhering
  • An inflation pipe connected to an end of the exhaust pipe close to the vacuum pump and configured to pass an inert gas into the exhaust pipe;
  • a first heating device disposed on the inflation tube and configured to heat an inert gas flowing into the inflation tube
  • a heat-preserving device is disposed on the exhaust pipe, and is used to heat the environment inside the exhaust pipe.
  • the method for preventing clogging of the vacuum pump pipeline and the chemical vapor coating machine provided by the present application by using a gas tube to fill the exhaust pipe connected to the vacuum pump with a hot inert gas, can increase the fluid pressure in the exhaust pipe, The gas and dust can flow out of the exhaust pipe smoothly; on the one hand, the oxygen concentration in the exhaust pipe can be reduced, and the reaction between the exhaust gas and oxygen is reduced, so as to reduce the further generation of powder in the exhaust pipe; further, through thermal inertia Gas can increase the ambient temperature in the exhaust pipe and intensify the molecular thermal movement of the gas and powder molecules, thereby effectively reducing the adhesion of powder in the exhaust pipe and improving the phenomenon of powder adhesion and clogging in the vacuum pump pipe. Simple reconstruction and low implementation cost are conducive to large-scale promotion.
  • FIG. 1 is a schematic structural diagram of a chemical vapor coating machine provided by an embodiment of the present application.
  • FIG. 2 is a schematic structural diagram of another chemical vapor coating machine provided by an embodiment of the present application.
  • FIG. 3 is a cross-sectional view of an exhaust pipe covered with a coating layer provided by the present application.
  • Label name Label name 1 Vacuum pump 17 Third heating device 12 Intake pipe 18 Insulation device 13 exhaust pipe 19 Coating layer 14 Inflatable tube 2 Process room 15 First heating device 3 Exhaust gas treatment device 16 Second heating device
  • the reaction gas flows from the gas source into the process chamber.
  • the by-products including a large amount of dust generated by the reaction and the gas not participating in the reaction are pumped out to the exhaust gas treatment device by the vacuum pump. Because the pipe diameter between the process chamber and the vacuum pump and between the vacuum pump and the exhaust gas treatment device is small and the length cannot be shortened, dust will accumulate on the inner wall of the pipeline, causing the pipeline to be blocked.
  • the vacuum in the exhaust pipe between the vacuum pump and the exhaust gas treatment device will gradually decrease, the exhaust gas concentration will rise, and the oxygen concentration will also increase rapidly, which will easily cause the exhaust gas and oxygen to react to form powder particles, and at the same time due to the exhaust pipe Low temperature in contact with the external environment can easily cause dust and powdery particles to adhere.
  • the present application provides a method for preventing powder clogging of a vacuum pump pipeline, which prevents powder from adhering to the vacuum pump exhaust pipe by introducing a heated inert gas into the vacuum pump exhaust pipe.
  • a heated inert gas By injecting heated inert gas into the exhaust pipe, on the one hand, the pressure in the exhaust pipe can be increased, and the gas or dust in the exhaust pipe can smoothly flow from the exhaust pipe to the exhaust gas treatment device; on the other hand, the oxygen in the exhaust pipe can be reduced. Concentration, so as to reduce the probability of powder particles formed by the reaction between exhaust gas and oxygen; further, the heated inert gas can increase the ambient temperature in the exhaust pipe and intensify the molecular movement of the molecules or dust, thereby further reducing the powder adhesion to the exhaust pipe wall.
  • various inert gases such as nitrogen and noble gases can be selected.
  • nitrogen can be selected, and the heating temperature of nitrogen can be selected from 90 ° to 100 °.
  • the exhaust pipe can be insulated.
  • a heat preservation device can be provided on the exhaust pipe to Insulation is performed at ambient temperature.
  • the insulation device can be insulation cotton sleeved on the surface of the exhaust pipe, such as glass wool layer and rock wool. It can also be a winding installed along the length of the exhaust pipe for the heating fluid.
  • the heat pipe may also be a helical braided silicone rubber heating belt that can heat the pipe after being energized, or other devices that can achieve an insulation effect on the exhaust pipe.
  • the inlet end pipe of the exhaust pipe can be heated.
  • the intake pipe connected between the process chamber and the vacuum pump can be heated to intensify the thermal movement of gas molecules and powder molecules in the intake pipe, thereby reducing the vacuum pump and the vacuum pump air inlet And the probability of powder adhesion at the air outlet.
  • the heating of the air intake pipe can choose to heat the entire air intake pipe, or heat the local pipe of the air intake pipe connected to the vacuum pump inlet, thereby saving costs and ensuring molecular activity in the vacuum pump.
  • a coating layer that can prevent powder from adhering can be further provided on the inner wall of the local pipeline at the intake port end of the exhaust pipe.
  • the material of the coating layer can be polysilicon Fluoroethylene.
  • Polytetrafluoroethylene is a polymer compound formed by the polymerization of tetrafluoroethylene. It has excellent chemical stability, corrosion resistance, temperature resistance, non-stickiness, electrical insulation and aging resistance.
  • the coating layer can also use other materials that can prevent the powder from adhering, which is not specifically limited in this embodiment.
  • the coating layer may also be provided at the outlet of the exhaust pipe and / or the middle section of the exhaust pipe, or a coating layer may be provided in the entire exhaust pipe to enhance the anti-powder blocking performance of the exhaust pipe.
  • the above-mentioned method for preventing the vacuum pump powder from clogging can effectively improve the clogging phenomenon caused by the powder adhesion in the vacuum pump pipeline.
  • the operation is convenient, simple and easy to implement, and the implementation cost is low, which is conducive to large-scale promotion.
  • This embodiment also provides a chemical vapor coating machine using the above-mentioned anti-vacuum pump powder blocking, as shown in FIGS. 1 and 2, including a vacuum pump 1, a process chamber 2, and an exhaust gas treatment device 3, and the process chamber 2 and the vacuum pump 1 communicate with each other.
  • An intake pipe 12 is provided, and an exhaust pipe 13 is connected between the vacuum pump 1 and the exhaust gas treatment device 3.
  • An end of the exhaust pipe 13 near the vacuum pump 1 is connected to an inflation pipe 14 for filling the exhaust pipe 13 with a hot inert gas.
  • a first heating device 15 for heating the inert gas is provided on the inflation pipe 14 to inflate.
  • An air source is connected to an end of the pipe 14 remote from the exhaust pipe 13.
  • the first heating device 15 may be a heat exchanger.
  • the inflation tube 14 is connected to the outlet of the heat exchanger, and the inlet of the heat exchanger is connected to an inert gas tank or other devices for storing inert gas.
  • the first heating device 15 may also be another device that can be used to heat an inert gas, which is not specifically limited in this embodiment.
  • the exhaust pipe 13 is provided with a heat insulation device 18, and the heat insulation device 18 may be the above-mentioned heat insulation layer, heat exchange tube, silicone rubber heating belt, or other devices capable of achieving the heat insulation function of the pipeline.
  • the insulation device 18 is a glass wool layer or other insulation layer, an insulation layer can be optionally provided on the entire outer wall of the exhaust pipe 13 to enhance the insulation effect on the exhaust pipe 13; when the insulation device 18 is selected as a heat exchange tube or silicone rubber
  • the heat insulation device 18 can be optionally installed in the middle pipe area of the exhaust pipe 13, especially when the exhaust pipe 13 has a vertically bent portion, as shown in FIG. 2, dust It is easy to cause accumulation and adhesion at the bent portion. Therefore, the thermal insulation device 18 can be optionally arranged in the bent area to intensify the molecular thermal movement in the place where the exhaust pipe 13 is easy to accumulate dust and reduce the probability of dust attachment.
  • a second heating device 16 is provided at the outlet end of the intake pipe 12 to increase the speed of the gas or dust entering the vacuum pump 1 so as to reduce the dust adhesion probability of dust at the inlet end of the vacuum pump 1 and the exhaust pipe 13; the inlet of the exhaust pipe 13
  • a second heating device 16 is provided at the end for intensifying molecular thermal movement at the air outlet of the vacuum pump 1.
  • the second heating device 16 and the third heating device 17 may be selected as devices capable of performing local heating, such as an electric heating pack or other devices, which are not specifically limited in this embodiment.
  • a coating layer 19 can be provided on the inner wall of the exhaust pipe 13 to prevent the powder from adhering.
  • the coating layer 19 may be provided in an area where the powder adheres easily on the exhaust pipe 13, such as in the area of the inlet end of the exhaust pipe 13; because the gas or dust may further increase the pressure at the outlet end of the exhaust pipe 13, resulting in The outlet end of the exhaust pipe 13 is more likely to produce powdery particles or dust adhesion than the middle position of the exhaust pipe 13.
  • the above-mentioned coating layer 19 can also be provided in the exit end region of the exhaust pipe 13; when the exhaust pipe 13 is bent In this case, dust is also easily caused by the bend, so that the coating layer 19 can be provided in the bend area of the exhaust pipe 13 to reduce the probability of powder adhesion.
  • the provision of the regionalized coating layer 19 can reduce the cost of providing the coating layer 19 as a whole of the exhaust pipe 13, and can also better reduce the probability of powder adhesion.
  • the coating layer 19 may be provided on the entire exhaust pipe 13.
  • the thickness of the coating layer 19 can be selected from 0.6 mm to 2 mm, and is preferably 2 mm.
  • the unreacted gas and the powder generated by the reaction enter the vacuum pump 1 through the intake pipe 12 and the gas entering the vacuum pump 1 It is discharged through the exhaust pipe 13 and enters the exhaust gas treatment device 3.
  • gas and powder are heated at the intake end of the exhaust pipe 13, and the heated inert gas is passed into the exhaust pipe 13 and the exhaust pipe 13 is heated.
  • a heat-retaining device 18 is provided to keep the gas and dust in the exhaust pipe 13 at a constant speed of molecular thermal motion, so as to be smoothly discharged through the exhaust pipe 13.
  • the inflating tube 14 to fill the exhaust pipe 13 with hot inert gas, the gas in the pipe at the end of the exhaust port is diluted, the probability of oxidative condensation reaction with the powder is reduced, and the exhaust gas is discharged.
  • the swirling air flow in the pipe at the mouth end reduces the probability of powder attachment at the exhaust port and the pipe at the exhaust port end; by heating the vacuum pump 1 pipeline to increase the speed of gas and powder molecules in the vacuum pump 1 pipeline Reduces the way that powder adheres to the inner wall of the vacuum pump 1 pipeline, effectively improves the phenomenon of powder adhesion and blockage in the vacuum pump 1 pipeline; by using the coating layer 19 of polytetrafluoroethylene, the powder on the inner wall of the vacuum pump 1 pipeline can be effectively delayed A condition that causes clogging. Convenient operation, simple reconstruction and low implementation cost are conducive to large-scale promotion.

Landscapes

  • Chemical & Material Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physical Vapour Deposition (AREA)
  • Chemical Vapour Deposition (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)

Abstract

一种防真空泵管路堵塞的方法，包括如下步骤：打开气源，反应气体从气源通入制程室（2）；制程室（2）中进行化学气相沉膜机镀膜反应；镀膜后，关闭气源，向连接于真空泵（1）出气口的排气管（13）通入加热的惰性气体；打开真空泵（1），制程室（2）中的粉尘及废气经排气管通（13）入废气处理装置。还公开了一种化学气相镀膜机。

Description

一种防真空泵管路堵塞的方法及化学气相镀膜机
技术领域
本申请涉及化学气相沉积镀膜设备技术领域，尤其涉及一种防真空泵管路堵塞的方法及化学气相镀膜机。
背景技术
化学气相沉膜机也叫真空镀膜机，主要指一类需要在较高真空度下进行的镀膜，具体包括很多种类，包括真空离子蒸发、磁控溅射、MBE分子束外延、PLD激光溅射沉积等很多种。
化学气相沉膜机在镀膜的过程中产生化学反应，在化学反应过程中产生反应物粉末，此反应后产生的粉末在随着系统内管路自制程室排出真空泵的过程中，因系统内管路的温度、压力、抽气效率的改变等，造成真空泵的管路内壁的粉末几率增大，附着堵塞管路。此粉末堵塞现象会引起真空泵浦的排气不顺畅、处理镀膜制程的腔体设备无法控压而停机。
真空泵管路内壁的堵塞，需要制程室停机，由维修人员拆卸真空泵的出口端管路，进行水洗清洁管路待管路风干；上述维修作业程序耗时约2小时，生产工作时间将减少百分之二十，降低了生产效率和设备利用率，同时增大了维修支出，增大了生产成本。
申请内容
本申请的目的在于提出一种防真空泵管路堵塞的方法，以有效改善真空泵管路内的粉末附着堵塞现象。
为达此目的，本申请采用以下技术方案：
一种防真空泵管路堵塞的方法，包括如下步骤：
打开气源，反应气体从所述气源通入制程室；
所述制程室中进行化学气相沉膜机镀膜反应；
镀膜后，关闭所述气源，向连接于真空泵出气口的排气管通入加热的惰性气体；
打开所述真空泵，所述制程室中的粉尘及废气经所述排气管通入废气处理装置。
作为本技术方案的可选方案，在向排气管通入加热的惰性气体之后，对所述排气管进行保温。
作为本技术方案的可选方案，在镀膜后及打开真空泵之前，加热连接于真空泵进气口的进气管。
作为本技术方案的可选方案，通过在所述排气管的内壁上镀上防粉尘附着的镀膜层以减少粉末在所述排气管内壁的附着几率。
本申请还提供了一种应用上述防真空泵管路堵塞的方法的化学气相镀膜机，以降低化学气相镀膜过程中，粉末在真空泵管路的附着几率。
为达到该目的，本申请采用下述技术方案：
一种应用上述防真空泵管路堵塞的方法的化学气相镀膜机，真空泵、制程室和废气处理装置，所述真空泵和所述制程室之间连接有进气管，所述废气处理装置和所述真空泵之间连接有排气管，所述排气管靠近所述真空泵的一端连通有充气管，所述充气管用于向所述排气管中充入惰性气体，所述充气管上设置有第一加热装置。
作为本技术方案的可选方案，所述排气管上设置有保温装置。
作为本技术方案的可选方案，还包括设置于所述进气管靠近所述真空泵一端的第二加热装置和/或所述排气管靠近所述真空泵一端的第三加热装置。
作为本技术方案的可选方案，至少所述排气管的进气口的内侧壁上镀有防粉尘附着的镀膜层。
作为本技术方案的可选方案，所述防粉尘附着的镀膜层为聚四氟乙烯层。
作为上述方案的替代方案，本申请提供了一种化学气相镀膜机，包括真空泵、制程室和废气处理装置，所述真空泵和所述制程室之间连接有进气管，所述废气处理装置和所述真空泵之间连接有排气管，其特征在于，还包括：
镀膜层，设置于所述进气管和所述排气管的内侧壁，用于防止粉尘附着；
充气管，连通于所述排气管靠近所述真空泵的一端，用于向所述排气管通入惰性气体；
第一加热装置，设置于所述充气管，用于对通入所述充气管的惰性气体进行加热；
保温装置，设置于所述排气管，用于对所述排气管内环境进行保温。
有益效果：本申请提供的防真空泵管路堵塞的方法及化学气相镀膜机，通过采用充气管向连接于真空泵的排气管内充入热的惰性气体，一方面可以提高排气管内的流体压力，使气体和粉尘能顺畅地从排气管内流出；一方面可以降低排气管内的氧气浓度，减小废气与氧气的反应，从而减少排气管中粉末的进一步生成；再者，通过热的惰性气体，可以提高排气管内的环境温度，加剧气体和粉末分子的分子热运动，从而有效减小粉末在排气管路内的附着，改善真空泵管路内粉末附着堵塞的现象。改造简易，实施成本低，利于大面积推广。
附图说明
为了更清楚地说明本申请实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本申请的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图示出的结构获得其他的附图。
图1是本申请实施例提供的化学气相镀膜机的结构示意图；
图2是本申请实施例提供的另一化学气相镀膜机的结构示意图；
图3是本申请提供的贴覆有镀膜层的排气管的横截面图。
附图标号说明：
标号 名称 标号 名称
1 真空泵 17 第三加热装置
12 进气管 18 保温装置
13 排气管 19 镀膜层
14 充气管 2 制程室
15 第一加热装置 3 废气处理装置
16 第二加热装置
本申请目的的实现、功能特点及优点将结合实施例，参照附图做进一步说明。
具体实施方式
下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本申请的一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
需要说明，本申请实施例中所有方向性指示（诸如上、下、左、右、前、后……）仅用于解释在某一特定姿态（如附图所示）下各部件之间的相对位置关系、运动情况等，如果该特定姿态发生改变时，则该方向性指示也相应地随之改变。
另外，在本申请中涉及“第一”、“第二”等的描述仅用于描述目的，而不能理解为指示或暗示其相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”的特征可以明示或者隐含地包括至少一个该特征。另外，各个实施例之间的技术方案可以相互结合，但是必须是以本领域普通技术人员能够实现为基础，当技术方案的结合出现相互矛盾或无法实现时应当认为这种技术方案的结合不存在，也不在本申请要求的保护范围之内。
下面结合附图和实施例对本申请作进一步的详细说明。可以理解的是，此处所描述的具体实施例仅仅用于解释本申请，而非对本申请的限定。另外还需要说明的是，为了便于描述，附图中仅示出了与本申请相关的部分而非全部结构。
在化学气相沉膜机镀膜过程中，反应气体从气源流入制程室，经反应室反应后，反应产生的副产物（包括大量粉尘）和未参与反应的气体由真空泵抽出至废气处理装置。由于连接制程室与真空泵及真空泵与废气处理装置之间的管路管径较小，且长度无法缩短，粉尘会堆积在管路的内壁上，造成管路堵塞；同时由于在废气排出过程中，尤其是真空泵与废气处置装置之间的排气管内的真空度会逐渐降低、废气浓度升高，氧气浓度也迅速升高，容易造成废气与氧气发生反应生成粉状颗粒物，且同时因排气管与外界环境接触而温度较低，容易导致粉尘和粉状颗粒物附着。
本申请提供了一种防真空泵管路粉末堵塞的方法，其通过向真空泵排气管内通入加热惰性气体防止粉末附着在真空泵排气管内。通过在排气管内通入加热惰性气体，一方面可以增加排气管内的压力，促使排气管内气体或粉尘顺利从排气管流出至废气处理装置；另一方面，可以降低排气管内的氧气浓度，从而降低废气与氧气发生反应产生粉末状颗粒物的概率；再者，加热的惰性气体可以提高排气管内的环境温度，加剧分子或粉尘的分子运动，从而进一步减小粉末附着在排气管内壁。
在本实施例中惰性气体可以选择为氮气、稀有气体等各种不易发生反应的气体，且综合经济和性能方面的考虑，可选为氮气，氮气的加热温度可选为90°~100°。
由于真空泵连接排气管的出口端处是压力升高变化最大的区域，废气浓度最大，最易产生粉末附着，因此加热惰性气体的入口应靠近真空泵的出口端。为防止排气管路过长导致远离惰性气体入口的管路温度逐渐减低，从而产生粉末附着，可以对排气管进行保温，具体地，可以在排气管路上设置保温装置以对排气管内的环境温度进行保温，保温装置可以为套设在排气管表面的保温棉，如玻璃棉层和岩棉等，也可以为沿排气管长度方向缠绕设置的、用于通入加热流体的换热管，还可以为通电后可加热管道的、螺旋状饶设的硅橡胶加热带，还可以为其他可以对排气管达到保温效果的其他装置。
为进一步加剧真空泵出口端处的分子热运动，降低粉尘在排气管入口端的堆积附着，可对排气管入口端管路进行加热。
为进一步减少粉末在管路内壁的堵塞，可以对连接于制程室和真空泵之间的进气管进行加热，加剧进气管内气体分子和粉末分子的热运动，从而减小真空泵内及真空泵进气口及出气口处的粉末附着概率。对进气管的加热可以选择对整个进气管进行加热，或对进气管连接于真空泵进气口的局部管路进行加热，从而在节省成本的同时保证进入真空泵中的分子活度。
由于排气管的进气口容易造成粉末堆积，因此可以进一步地通过在排气管的进气口端的局部管路的内壁设置可以防止粉末附着的镀膜层，镀膜层的材料可选为聚四氟乙烯。聚四氟乙烯为四氟乙烯经聚合而成的高分子化合物，具有优良的化学稳定性、耐腐蚀性、耐温性、不粘性、电绝缘性和抗老化性。由于其化学稳定性，其不会同进入排气管的废气或粉末产生反应；因其耐温性好，在-180°C~260°C范围内性能相差较小，因此对管道的加热、保温或充热惰性气体不会影响其性能；由于其不粘性，可以使粉尘在其上的附着能力差，从而易被废气处理装置吸走，从而有效延缓真空泵管路内壁的粉末附著引起堵塞的状况。镀膜层也可以采用其他可以达到防止粉末附着的其他材料，本实施例不做具体限制。
镀膜层还可以设置在排气管的出口和/或排气管中间段区域，或在整个排气管内部均设置镀膜层，以加强排气管的防粉末堵塞性能。
上述防真空泵粉末堵塞方法，可以有效改善真空泵管路内的粉末附着导致的堵塞现象，操作方便，简单易行，且实施成本较低，有利于大面积的推广。
本实施例还提供了一种应用上述防真空泵粉末堵塞的化学气相镀膜机，如图1和2所示，包括真空泵1、制程室2和废气处理装置3，制程室2和真空泵1之间连通有进气管12，真空泵1和废气处理装置3之间连接有排气管13。排气管13靠近真空泵1的一端管路上连通有充气管14，用于向排气管13中充入热惰性气体，充气管14路上设置有对惰性气体进行加热的第一加热装置15，充气管14远离排气管13的一端连接有气源。第一加热装置15可以为换热器，充气管14连接于换热器的出口，换热器的入口连接惰性气体罐或其他用于存储惰性气体的装置。第一加热装置15也可以为其他可用于加热惰性气体的装置，本实施例不做具体限制。
排气管13上设置有保温装置18，保温装置18可以为上述提及的保温层、换热管、硅橡胶加热带或其他能达到管道保温功能的装置。当保温装置18为玻璃棉层等保温层时，可选在整个排气管13外壁均设置保温层，以增强对排气管13的保温效果；当保温装置18选择为换热管或硅橡胶加热带等可以加热保温的装置时，可选将保温装置18设置在排气管13的中间管路区域，特别是当排气管13路有垂直弯折部分时，如图2所示，粉尘容易在弯折部分产生堆积粘附，因此可选将保温装置18设置在弯折区域，以加剧在排气管13容易堆积粉尘处的分子热运动，减低粉尘附着的几率。
进气管12的出口端设置有第二加热装置16，用于加剧进入真空泵1的气体或粉尘运动速度，从而降低粉尘在真空泵1及排气管13进口端的粉尘附着概率；排气管13的入口端设置有第二加热装置16，用于加剧真空泵1出气口处的分子热运动。第二加热装置16和第三加热装置17可选择为能进行局部加热的装置，如采用电加热的热敷袋或其他装置，本实施例不做具体限制。
如图3所示，为进一步防止粉尘在排气管13内附着，可以在排气管13路的内壁设置一层防止粉末附着的镀膜层19。镀膜层19可设置在排气管13上容易产生粉末附着的区域，如在排气管13的入口端区域；由于气体或粉尘在排气管13出口端会存在压力的进一步升高，从而导致排气管13出口端相对排气管13中间位置更容易产生粉状颗粒物或粉尘附着，因此，也可以在排气管13的出口端区域设置上述镀膜层19；当排气管13存在弯折时，弯折处也容易造成粉尘堆积，从而可以在排气管13的弯折区域设置上述镀膜层19以降低粉末附着的概率。区域化镀膜层19的设置可以降低排气管13整体设置镀膜层19的成本，同时也可以较好地实现降低粉末附着的概率。在具体实施中，也可以对整个排气管13设置镀膜层19。为保证镀膜层19的防止附着的功效，镀膜层19的厚度可选为0.6mm-2mm，且最优为2mm。
本实施例提供的化学气相镀膜机，当气体从气源处进入制程室2完成化学气相镀膜反应后，未反应的气体和反应产生的粉末等经由进气管12进入真空泵1，进入真空泵1的气体经由排气管13排出并进入废气处理装置3，期间，气体和粉末在排气管13的进气端被加热，且通过向排气管13通入加热的惰性气体及在排气管13上设置保温装置18而使排气管13内的气体和粉尘保持一定的速度的分子热运动，从而顺利经过排气管13排出。
综上所述，通过采用充气管14将热的惰性气体充入排气管13路中，稀释了排气口端管路内的气体，减少了与粉末发生氧化凝聚反应的概率，使得排气口端管路内的气流回旋，减少了粉末在排气口处及排气口端管路附着的几率；通过对真空泵1管路进行加热以提高真空泵1管路内气体和粉末分子运动的速度减少粉末附着在真空泵1管路内管壁上的方式，有效的改善了真空泵1管路内的粉末附着堵塞现象；通过采用聚四氟乙烯的镀膜层19可以有效延缓真空泵1管路内壁的粉末附著引起堵塞的状况。操作方便，改造简易，实施成本低，利于大面积推广。
以上结合具体实施例描述了本申请的技术原理。这些描述只是为了解释本申请的原理，而不能以任何方式解释为对本申请保护范围的限制。基于此处的解释，本领域的技术人员不需要付出创造性的劳动即可联想到本申请的其它具体实施方式，这些方式都将落入本申请的保护范围之内。

Claims (17)

  1. 一种防真空泵管路堵塞的方法，其中，包括如下步骤：
    打开气源，反应气体从所述气源通入制程室；
    所述制程室中进行化学气相沉膜机镀膜反应；
    镀膜后，关闭所述气源，向连接于真空泵出气口的排气管通入加热的惰性气体；
    打开所述真空泵，所述制程室中的粉尘及废气经所述排气管通入废气处理装置。
  2. 根据权利要求1所述的防真空泵管路堵塞的方法，其中，在向排气管通入加热的惰性气体之后，对所述排气管进行保温。
  3. 根据权利要求1所述的防真空泵管路堵塞的方法，其中，在镀膜后及打开真空泵之前，加热连接于真空泵进气口的进气管。
  4. 根据权利要求1所述的防真空泵管路堵塞的方法，其中，通过在所述排气管的内壁上镀上防粉尘附着的镀膜层以减少粉末在所述排气管内壁的附着几率。
  5. 根据权利要求2所述的防真空泵管路堵塞的方法，其中，通过在所述排气管的内壁上镀上防粉尘附着的镀膜层以减少粉末在所述排气管内壁的附着几率。
  6. 根据权利要求3所述的防真空泵管路堵塞的方法，其中，通过在所述排气管的内壁上镀上防粉尘附着的镀膜层以减少粉末在所述排气管内壁的附着几率。
  7. 一种化学气相镀膜机，包括真空泵、制程室和废气处理装置，所述真空泵和所述制程室之间连接有进气管，所述废气处理装置和所述真空泵之间连接有排气管，其中，所述排气管靠近所述真空泵的一端连通有充气管，所述充气管用于向所述排气管中充入惰性气体，所述充气管上设置有第一加热装置，所述化学气相镀膜机设置为防真空泵管路堵塞的方法，包括如下步骤：
    打开气源，反应气体从所述气源通入制程室；
    所述制程室中进行化学气相沉膜机镀膜反应；
    镀膜后，关闭所述气源，向连接于真空泵出气口的排气管通入加热的惰性气体；
    打开所述真空泵，所述制程室中的粉尘及废气经所述排气管通入废气处理装置。
  8. 根据权利要求7所述的化学气相镀膜机，其中，所述化学气相镀膜机设置为防真空泵管路堵塞的方法，还包括如下步骤：
    在向排气管通入加热的惰性气体之后，对所述排气管进行保温。
  9. 根据权利要求8所述的防真空泵管路堵塞的方法，其中，所述化学气相镀膜机设置为防真空泵管路堵塞的方法，还包括如下步骤：
    通过在所述排气管的内壁上镀上防粉尘附着的镀膜层以减少粉末在所述排气管内壁的附着几率。
  10. 根据权利要求7所述的化学气相镀膜机，其中，所述化学气相镀膜机设置为防真空泵管路堵塞的方法，还包括如下步骤：
    在镀膜后及打开真空泵之前，加热连接于真空泵进气口的进气管。
  11. 根据权利要求10所述的防真空泵管路堵塞的方法，其中，所述化学气相镀膜机设置为防真空泵管路堵塞的方法，还包括如下步骤：
    通过在所述排气管的内壁上镀上防粉尘附着的镀膜层以减少粉末在所述排气管内壁的附着几率。
  12. 根据权利要求7所述的防真空泵管路堵塞的方法，其中，通过在所述排气管的内壁上镀上防粉尘附着的镀膜层以减少粉末在所述排气管内壁的附着几率。
  13. 根据权利要求7所述的化学气相镀膜机，其中，所述排气管上设置有保温装置。
  14. 根据权利要求7所述的化学气相镀膜机，其中，还包括设置于所述进气管靠近所述真空泵一端的第二加热装置和/或所述排气管靠近所述真空泵一端的第三加热装置。
  15. 根据权利要求7所述的化学气相镀膜机，其中，至少所述排气管的进气口的内侧壁上镀有防粉尘附着的镀膜层。
  16. 根据权利要求15所述的化学气相镀膜机，其中，所述防粉尘附着的镀膜层为聚四氟乙烯层。
  17. 一种化学气相镀膜机，包括真空泵、制程室和废气处理装置，所述真空泵和所述制程室之间连接有进气管，所述废气处理装置和所述真空泵之间连接有排气管，其中，还包括：
    镀膜层，设置于所述进气管和所述排气管的内侧壁，用于防止粉尘附着；
    充气管，连通于所述排气管靠近所述真空泵的一端，用于向所述排气管通入惰性气体；
    第一加热装置，设置于所述充气管，用于对通入所述充气管的惰性气体进行加热；
    保温装置，设置于所述排气管，用于对所述排气管内环境进行保温。
PCT/CN2018/115304 2018-07-04 2018-11-14 一种防真空泵管路堵塞的方法及化学气相镀膜机 Ceased WO2020006956A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US16/316,348 US11028475B2 (en) 2018-07-04 2018-11-14 Method for preventing vacuum pump pipeline from blockage, and chemical vapor deposition machine

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201810724322.9A CN108754455A (zh) 2018-07-04 2018-07-04 一种防真空泵管路堵塞的方法及化学气相镀膜机
CN201810724322.9 2018-07-04

Publications (1)

Publication Number Publication Date
WO2020006956A1 true WO2020006956A1 (zh) 2020-01-09

Family

ID=63976028

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2018/115304 Ceased WO2020006956A1 (zh) 2018-07-04 2018-11-14 一种防真空泵管路堵塞的方法及化学气相镀膜机

Country Status (3)

Country Link
US (1) US11028475B2 (zh)
CN (1) CN108754455A (zh)
WO (1) WO2020006956A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114059043A (zh) * 2021-11-19 2022-02-18 新美光(苏州)半导体科技有限公司 进气机构及气相沉积设备

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108754455A (zh) * 2018-07-04 2018-11-06 惠科股份有限公司 一种防真空泵管路堵塞的方法及化学气相镀膜机
CN111621769A (zh) * 2019-02-28 2020-09-04 长鑫存储技术有限公司 半导体制造装置的排气管道
US11530479B2 (en) * 2019-10-18 2022-12-20 Taiwan Semiconductor Manufacturing Company, Ltd. Atomic layer deposition tool and method
CN111075999A (zh) * 2019-11-29 2020-04-28 唐山科源环保技术装备有限公司 避免焦油冷凝堵塞发生炉热煤气管道装置及工艺
CN115522177B (zh) * 2021-07-23 2023-05-09 上海汉钟精机股份有限公司 用于太阳能电池片的镀膜工艺的智能排粉控制方法
CN114300330B (zh) * 2021-12-28 2024-07-26 上海华力微电子有限公司 一种干泵尾管和离子注入机
CN115044972A (zh) * 2022-06-10 2022-09-13 中环领先半导体材料有限公司 一种减少外延尾气管路堵塞和气体反灌腔体的结构
CN116945555A (zh) * 2023-07-17 2023-10-27 苏州仕通电子科技有限公司 一种具有消泡结构的吸塑托盘成型模具

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070095282A1 (en) * 2005-08-01 2007-05-03 Byoung-Hoon Moon Apparatus for manufacturing semiconductor device with pump unit and method for cleaning the pump unit
CN102304702A (zh) * 2011-09-23 2012-01-04 深圳市华星光电技术有限公司 用于化学气相沉积机台的真空泵的排气管及相应的真空泵
CN102560418A (zh) * 2010-12-29 2012-07-11 理想能源设备有限公司 化学气相沉积装置
CN203474891U (zh) * 2013-09-23 2014-03-12 中芯国际集成电路制造(北京)有限公司 防止气管堵塞的装置
CN104074717A (zh) * 2013-03-28 2014-10-01 株式会社荏原制作所 带除害功能的真空泵
CN206768209U (zh) * 2017-05-15 2017-12-19 无锡荣坚五金工具有限公司 一种化学原料进料管道吹扫装置
CN108754455A (zh) * 2018-07-04 2018-11-06 惠科股份有限公司 一种防真空泵管路堵塞的方法及化学气相镀膜机

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070095282A1 (en) * 2005-08-01 2007-05-03 Byoung-Hoon Moon Apparatus for manufacturing semiconductor device with pump unit and method for cleaning the pump unit
CN102560418A (zh) * 2010-12-29 2012-07-11 理想能源设备有限公司 化学气相沉积装置
CN102304702A (zh) * 2011-09-23 2012-01-04 深圳市华星光电技术有限公司 用于化学气相沉积机台的真空泵的排气管及相应的真空泵
CN104074717A (zh) * 2013-03-28 2014-10-01 株式会社荏原制作所 带除害功能的真空泵
CN203474891U (zh) * 2013-09-23 2014-03-12 中芯国际集成电路制造(北京)有限公司 防止气管堵塞的装置
CN206768209U (zh) * 2017-05-15 2017-12-19 无锡荣坚五金工具有限公司 一种化学原料进料管道吹扫装置
CN108754455A (zh) * 2018-07-04 2018-11-06 惠科股份有限公司 一种防真空泵管路堵塞的方法及化学气相镀膜机

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114059043A (zh) * 2021-11-19 2022-02-18 新美光(苏州)半导体科技有限公司 进气机构及气相沉积设备
CN114059043B (zh) * 2021-11-19 2023-10-03 新美光(苏州)半导体科技有限公司 进气机构及气相沉积设备

Also Published As

Publication number Publication date
US20200208262A1 (en) 2020-07-02
US11028475B2 (en) 2021-06-08
CN108754455A (zh) 2018-11-06

Similar Documents

Publication Publication Date Title
WO2020006956A1 (zh) 一种防真空泵管路堵塞的方法及化学气相镀膜机
CN104060236B (zh) 一种片状基片的连续镀膜生产系统
CN102353240B (zh) 低温干燥柜及其干燥方法
CN203700512U (zh) 等离子体增强化学气相沉积腔室
CN119694941A (zh) 一种半导体设备的工艺腔室及半导体设备
CN108211077A (zh) 一种加热型管路及其加工工艺
CN104451601B (zh) 一种常压化学气相沉积镀膜反应器
CN213951339U (zh) 一种硅片沉积设备
CN210529053U (zh) 金刚石薄膜连续制备使用的hfcvd设备
CN216791270U (zh) 一种热风循环隧道烘箱检测装置
CN116399087A (zh) 一种鞋垫生产用的高效率鞋垫烘干机
CN208075483U (zh) 一种用于导热硅胶加工的真空烤箱
CN220965957U (zh) 一种猴舍用供暖装置
CN107579026B (zh) 一种用于湿法刻蚀的干燥喷嘴、湿法刻蚀设备
CN206692728U (zh) 一种气体分配器、薄膜沉积设备
CN207926019U (zh) 一种线路易整理的散热电力柜
CN208597230U (zh) 温度控制装置及机柜系统
CN106016977A (zh) 干燥装置
CN216640016U (zh) 一种基于电热管的干衣柜
TWI900340B (zh) Cda加熱裝置
CN106091647A (zh) 一种耐火材料砖的干燥装置
CN222634676U (zh) 太阳能空调新风预加热装置
CN218337009U (zh) 一种救火机器人的散热结构
CN117188830B (zh) 一种汗蒸淋浴房及其制备方法
TWI911966B (zh) 用以輸送氣體之多層絕熱管路

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18925231

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC

122 Ep: pct application non-entry in european phase

Ref document number: 18925231

Country of ref document: EP

Kind code of ref document: A1