Patent ID: 7439112
Filing Date: 2008-10-21
Classification: H01L

Abstract:
1. A method for manufacturing a semiconductor device including a semiconductor substrate including a first region and a second region adjacent to the first region, comprising: forming a buried oxide layer on the semiconductor substrate and a first semiconductor layer on the buried oxide layer in the first and the second regions by use of a wafer bonding method; removing the first semiconductor layer, the buried oxide layer and the semiconductor substrate in the first region so that a height of a first upper surface of the semiconductor substrate of the first region is lower than a second upper surface of the semiconductor substrate of the second region; forming a protection film on a sidewall of the first semiconductor layer exposed by the removing step; forming a second silicon layer on the first upper surface of the semiconductor substrates so that a height of a third upper surface of the second silicon layer of the first region is the same as a height of a fourth upper surface of the first semiconductor layer in the second region; forming a cell transistor at the third upper surface of the second silicon layer in the first region and a cell capacitor from the second silicon layer to the semiconductor substrate in the first region, and a second transistor at the fourth upper surface of the first semiconductor layer in the second region.