摘要 |
First, an isolation region is formed on a surface portion of a semiconductor substrate of silicon, thereby defining first and second regions, which are isolated from each other by the isolation region, on the semiconductor substrate. Next, a tantalum oxide film is formed in the first region on the semiconductor substrate. Then, a silicon dioxide film is formed in the second region on the semiconductor substrate by heat-treating the semiconductor substrate within an ambient containing oxygen as a main component. Subsequently, first and second gate electrodes are formed on the tantalum oxide and silicon dioxide films, respectively. Thereafter, first and second gate insulating films are formed by etching the tantalum oxide and silicon dioxide films using the first and second gate electrodes as respective masks.
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