摘要 |
This is a method of forming a semiconductor-on-insulator wafer with a single-crystal semiconductor substrate. The method comprises: anisotropically etching a substrate 22 to form trenches 24 having walls and bottoms; anisotropically depositing oxide 26,28,34 over a surface of the substrate 22 and on the trench 24 walls and bottoms; etching to remove trench wall oxide 28, but leaving oxide 26,34 over the semiconductor surface 22 and on the trench 24 bottom, thereby creating seed holes which expose portions of the semiconductor substrate 22; epitaxially growing semiconductor material 32 on the exposed portions of the semiconductor substrate 22 to partially fill the trenches; depositing nitride; anisotropically etching the nitride to form nitride sidewalls 36; forming oxide 40 on top of the grown semiconductor material; removing nitride sidewalls 36; anisotropically etching semiconductor 42 until the buried oxide 34 is reached, thereby leaving islands of semiconductor material 44 on the buried oxide layer 34; thermally growing oxide 46 on areas of exposed semiconductor; anistropically etching oxide 40 to expose the top of the semiconductor islands 44; and epitaxially growing semiconductor material 48 to merge the semiconductor islands 44 and create a layer of single-crystal semiconductor material which is insulated from the substrate 22.
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