Mass flow controller on-line correction device

Abstract

The invention relates to the technical field of microelectronics, in particular to the on-line calibration of MFC (mass flow controller) used in the gas path system of semiconductor equipment. A new type of mass flow controller online calibration device disclosed by the present invention includes: a temperature sensor, a vacuum gauge, an air box and a mass flow controller connected thereto, a dry pump, and a chamber, a normally closed inlet valve . A normally closed outlet valve and its control device, wherein the normally closed inlet valve and the normally closed outlet valve are connected to the chamber.

Description

technical field [0001] The invention relates to the technical field of microelectronics, in particular to the on-line calibration of MFC (mass flow controller) used in the gas path system of semiconductor equipment. Background technique [0002] The mass flow of gas needs to be precisely controlled in semiconductor equipment; the different processes of each equipment require different gas flow ratios. Such as figure 1 Shown is the structure of a gas path in the prior art. However, after the mass flow controller MFC is used for a period of time, due to various reasons, the zero point drift may occur. The zero drift of the mass flow controller MFC will cause process instability, which will affect the overall chip yield. Therefore, the calibration of mass flow controller MFC is very important in semiconductor equipment. [0003] Such as figure 2 As shown, it is another technical solution of the prior art. It calibrates the mass flow controllers in the entire gas circuit ...

AI Technical Summary

Problems solved by technology

The disadvantages of this solution are: 1. Since there are multiple channels of gas in the gas circuit board, when the calibration of each mass flow controller is required, if the calibration mass flow controller MFC is a digital mass flow controller MFC, each channel The gas category needs to be reset before calibration

2. Since there are multiple mass flow controllers MFC in the gas circuit board, the measurement range of each mass flow controller MFC is different

The disadvantages of this scheme are: 1. The measurement accuracy is greatly affected by various conditions of the reaction chamber, such as the temperature of the reaction chamber, the volume of the reaction chamber, the cleanliness of the surface of the reaction chamber, etc.; 2. The flow rate of the mass flow controller MFC to be calibrated Limited; if the flow range of the mass flow controller MFC itself is relatively small, the reaction chamber is relatively large, so the calibration time will be very long, and sometimes it cannot be calibrated at all

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