Removal method of water vapor on crystal wafer surface

Abstract

The invention provides a removal method of water vapor on the crystal wafer surface, comprising the following steps of setting the temperature of a reaction cavity which is set for containing a crystal wafer; putting the crystal wafer in the reaction cavity; inputting nitrogen into the reaction cavity for the first time and exhausting the nitrogen through an exhaust pipeline of the reaction cavity; inputting hydrogen or mixed gas of the hydrogen and the nitrogen into the reaction cavity and exhausting the hydrogen or the mixed gas of the hydrogen and the nitrogen through the exhaust pipeline of the reaction cavity; inputting the nitrogen into the reaction cavity for the second time and exhausting the nitrogen through the exhaust pipeline of the reaction cavity; and taking out the crystal wafer from the reaction cavity. In the invention, nitrogen used in the prior art is replaced with hydrogen so as to completely remove the water vapor on the crystal wafer surface. When being used as an accompany film in a silicon dioxide diaphragm growth technology, the crystal wafer can obviously improve the uniformity of the thickness of a silicon dioxide diaphragm. In addition, the use of hydrogen is also beneficial to removing the water vapor adsorbed on the inner surface of the reaction cavity.

Description

technical field [0001] The invention relates to a film growth process in the field of semiconductors, in particular to a method for removing water vapor on the surface of a wafer. Background technique [0002] Silicon dioxide film is a very important film in semiconductor devices, which can be used as gate oxide layer, gate side selective oxide layer and buffer oxide layer. Silicon dioxide film growth is carried out in the reaction chamber, and requires a silicon companion. A typical reaction chamber can hold up to 170 wafers, of which 150 are product wafers, and 20 are silicon accompanying wafers placed at both ends of the product wafer. If there are less than 150 product wafers, additional silicon companion wafers need to be loaded until it is full. Therefore, in each growth process, a large number of silicon companion wafers are required. The surface of the silicon wafer must be clean, the most important of which is the control of water vapor. [0003] As the critical...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problem of incomplete removal of water vapor on the surface of the silicon companion in the prior art, the present invention provides a method for completely removing the water vapor adsorbed on the surface of the silicon companion, and achieves the purpose of improving the thickness uniformity of the silicon dioxide film

Images