A vaporization supply device and method of liquid raw material for chemical vapor deposition

Abstract

A liquid raw material vaporization supply device for chemical vapor deposition and its use method. The supply device includes a liquid storage tank, an electronic scale, a vaporization chamber, a gas supply system, a pipeline, a regulating valve, a stop valve, a vacuum pump and a vacuum gauge; The method includes: 1. Preparatory stage; 2. Flow regulation stage; 3. Stable and constant air supply stage; 4. Shutdown stage. Compared with the existing liquid raw material vaporization supply system, the device can accurately measure the flow rate of liquid raw material vaporization steam in real time, and can adjust and control the opening of the feeding valve in real time according to the change of process parameters in the CVD production system , so that the vaporization flow rate of the liquid raw material is adjustable, controllable, and kept uniform, thereby providing a favorable liquid raw material vaporization supply device for chemical vapor deposition (CVD) production equipment.

Description

technical field [0001] The invention relates to the technical field of chemical vapor deposition, in particular to a liquid raw material vaporization supply device for chemical vapor deposition whose flow rate can be adjusted in real time and its use method. Background technique [0002] Chemical vapor deposition (CVD) technology is currently widely used in the preparation of nanomaterials, semiconductor materials, and thin film materials. The working principle of CVD technology is generally to continuously introduce one or more gaseous raw materials into a pre-evacuated reaction chamber. Under appropriate conditions (heating, microwave, laser, plasma, etc.), the gaseous raw materials undergo chemical reactions. The only solid product is generated, which is deposited in the form of film, powder, etc., while other products and remaining raw materials must exist in gaseous form and be sucked away by a vacuum pump. Therefore, people can obtain pure solid chemical products with...

AI Technical Summary

Problems solved by technology

[0005] 1. Cannot measure in real time

Since the heating vaporizer is connected by pipelines, it is impossible to directly measure the quality change of the liquid raw material stored in it in real time. It can only be measured before and after the completion of the operation, that is, only the period calculation of the average flow rate of the liquid raw material can be realized, and the real-time measurement of the steam flow rate cannot be realized.

However, there are many factors in the CVD production process that will affect the evaporation, vaporization, supply and transportation of liquid raw materials, so it is very easy to have unstable flow of liquid raw material vapor in the middle process

[0006] 2. Cannot adjust and control in real time

Since the real-time measurement of the liquid raw material vapor flow cannot be realized, it is also impossible to realize real-time control and adjustment of the liquid raw material vapor flow according to the actual deposition parameter changes in the CVCD production process

[0007] 3. The total amount of liquid raw materials is limited

When the chemical reaction time of the CVD process is long and the amount of liquid raw materials used is large, if one-time charging is used, the preheating preparation time in the early stage will be longer, and the vaporization state before and after the whole working cycle is very different; Change the pressure and temperature in the supply system. During this period, it is difficult to maintain a constant flow of liquid raw material vapor

[0008] 4. The repeatability of multiple production is poor

Due to factors such as the neutral position of the flow control adjustment valve, it is difficult to make every position adjustment strictly and accurately, and the repeatability is difficult to guarantee.

In the absence of real-time monitoring of the vapor flow of liquid raw materials, it is difficult to guarantee the consistency of process parameters in different batches of production

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