| 摘要 |
<p>This is a method of forming a semiconductor-on-insulator wafer with a single-crystal semiconductor substrate. Preferably 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; anisotropically 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. This is also a semiconductor-on-insulator wafer structure. The wafer comprises: trenches 24 having walls and bottoms in a single-crystal semiconductor substrate (e.g. silicon substrate 22 ; a first insulator (e.g. oxide 20,26,34) on a surface of the substrate and on the trench bottoms; a second insulator (e.g. oxide 46) on the trench walls; and a layer of single-crystal semiconductor material (e.g. silicon epilayer 48) on the surface and extending into the trenches, with the layer being insulated from the substrate. <IMAGE></p> |
