| 摘要 |
PURPOSE: An improvement method of a non-uniformity of an etched body is provided to prevent damages of layers under a poly-crystalline silicon layer by restraining an overetch of the poly-crystalline silicon in a peripheral region. CONSTITUTION: A semiconductor substrate(21) having a compactly patterned first region and a loosely patterned second region is previously supplied. Then, a nitride layer as an etch buffer is secondly formed on the loosely patterned second region. A poly-crystalline silicon layer(33) as an etched layer is thirdly formed on the entire surface of the resultant structure. Then, the poly-crystalline silicon layer(33) is etched using a CMP(Chemical Mechanical Polishing). At this point, the etch buffer prevents a non-uniform etch of the poly-crystalline silicon layer(33), thereby keeping a constant height of the poly-crystalline silicon layer(33), so that damages caused by an overetching is improved.
|
