| 摘要 |
<p>A manufacturing method of SONOS semiconductor device capable of improving productivity is provided to reduce the number of process mask by using nitride film on logic region as hard mask. An ONO(Oxide-Nitride-Oxide) layer is formed on a semiconductor substrate. The ONO layer besides a memory region(A) and high voltage region(High V) is removed by first-etching with a first photo resist as a first mask. A first gate oxide film is formed on a front surface of the semiconductor substrate. The first gate oxide film and an oxide film of the ONO layer besides the memory region and a ultra high voltage region(Ultra V) are removed by second-etching with a second photo resist and a nitride film of the high voltage region as a second mask. The nitride film of the high voltage region is removed by third-etching on the semiconductor substrate. A second gate oxide film is formed on the semiconductor substrate including a low voltage region(Low V).</p> |
