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Thin film deposition is to deposit a film on the main substrate material of the semiconductor. This film can be made of various materials, such as insulating compound silicon dioxide, semiconductor polysilicon, metallic copper, etc. The equipment used for coating is called thin film deposition equipment. Thin film preparation processes can be divided into two categories according to their film formation methods.: Physical vapor deposition (PVD) and chemical vapor deposition (CVD), among which CVD process equipment accounts for a higher proportion. Chemical Vapor Deposition (CVD) is a process that uses gaseous or vaporous substances to react in the gas phase or at the gas-solid interface to form solid deposits. The chemical vapor deposition process is divided into three important stages: The reactive gas diffuses to the surface of the substrate, the reactive gas is adsorbed on the surface of the substrate, a chemical reaction occurs on the surface of the substrate to form a solid deposit, and the generated gas phase by-products leave the surface of the substrate. The most common chemical vapor deposition reactions are: thermal decomposition reactions, chemical synthesis reactions and chemical transport reactions. In the semiconductor CVD process, one or more precursor gases are usually used. These gases chemically react in a reaction chamber to produce solid thin film materials, which are then deposited on the surface of the semiconductor wafer. The CVD process can be implemented through different methods such as thermal CVD, plasma CVD, and metal-organic CVD. Common gases include: Silica precursor gas (such as silica ether, chlorosilane), nitrogen, ammonia, silicon source gas (such as trimethylsilane, trichlorosilane), hydrogen, etc. For different precursor gases, the flow rate needs to be accurately controlled to ensure the accuracy and stability of the reaction. for example: In a typical MOCVD setup, a liquid metal-organic precursor located in a separate solution chamber is gently heated as needed, sprayed or bubbled to dissolve the precursor gas, and delivered into the MOCVD reactor with a high-purity carrier gas (usually nitrogen or hydrogen) through a flow controller. Controlled flash evaporator. The temperature of this transfer line is precisely controlled to avoid condensation or premature reaction of the precursor before introduction into the MOCVD reactor. The precursor, along with high-purity reactive gases, flows through a special orifice manifold designed to provide uniform deposition and thickness on the heated substrate. Recommended related articles: "Application of liquid flow sensor for monitoring thermal gas mass flow controller in vacuum coating machine" The importance of MFC mass flow controller in CVD equipment: MFC (Mass Flow Controller) is widely used to control and monitor the flow of various gases. Among them, applications in CVD: flow control: MFC is critical to the operation of CVD equipment. It can accurately measure and regulate the flow into the reaction chamber to ensure the accurate supply of reaction gas. This is critical to control film thickness and avoid film non-uniformity caused by flow changes. Stability monitoring: MFC can monitor fluid flow changes in real time to ensure the stability and consistency of the CVD process. This monitoring helps promptly detect and resolve equipment failures and maintain equipment performance. Program control: MFC can control fluid flow changes through preset programs, thereby automating and programming the CVD process. This helps increase productivity and reduce human operating errors. The following is a high-precision, wide-range optional flow controller MFC2000 series from SIARGO of the United States, which ISWEEK is an agent for. The MFC2000 series mass flow controller uses the company's proprietary MEMS Thermal-D operating "thermal sensing technology" with intelligent control electronics. This unique mass flow sensing technology eliminates gas sensitivity of some gases with similar diffusivities and allows gas identification after programming. This product can be used for process control with a dry dynamic range of 100:1, and its control range is a pressure of 0.1 to 0.8MPa (15 to 120 PSL) and a compensation temperature of 0 to 50°C. Measuring ranges are available from 50mL/min to 200L/min, with digital RS485 Modbus communication and analog output. The product is designed for easy replacement of mechanical connectors, with standard connectors available in dual ferrule, VCR or UNF, with other custom connectors available upon request. SIARGO's MFC2000 flow controller plays a very important role in CVD equipment. It can accurately measure and control the size of gas, and can achieve high temperature, high precision, and high resolution film deposition processes.