METHOD FOR FORMING GATE OXIDE WITH INCREASED DEVICE RELIABILITY

摘要

PURPOSE: A method for forming a gate oxide with increased device reliability is provided to be capable of preventing the increase of leakage current at a thin gate oxide layer and simultaneously improving the reliability of a thick gate oxide layer as a double or multiple gate oxide layer is formed. CONSTITUTION: The first and second oxide layer(40,50) are formed on a substrate(10). At this time, the first thickness of the first oxide layer is different from the second thickness of the second oxide layer. A plasma nitridation is carried out on the first and second oxide layer. Then, an oxidation is carried out on the first and second oxide layer under the atmosphere of oxygen gas. At this time, the hydrogen gas is added to the oxygen gas. Preferably, the oxidation is performed in the temperature of 700-1000 °C.