Method for improving quality of gate oxide

The invention provides a method for improving quality of a gate oxide. The method is characterized by including the steps of providing a silicon substrate, removing a natural oxide layer on the surface of the silicon substrate through a wet cleaning process, continuing to place the silicon substrate into a furnace pipe to be oxidized at a high temperature so that the gate oxide can be formed on the surface of the silicon substrate, wherein a carbon fiber heating pipe serves as a heating source of the furnace pipe so that high-temperature oxidization can be conducted, the preset temperature of the furnace pipe at the wafer cassette loading waiting stage is set as T, and T ranges from 400 DEG C to 700 DEG C. The carbon fiber heating pipe serves as the heating source of the furnace pipe, and therefore time for waiting for temperature rise and temperature fall of a wafer cassette can be shortened, foreign oxide layers are prevented from growing, and quality of the gate oxide is effectively improved.