Methods for fabricating semiconductor structures

A method for fabricating a corrugated structure in a semiconductor surface, comprising:

• providing a first semiconductor layer;
• providing a second semiconductor layer on the first semiconductor layer, where the second semiconductor layer comprises a semiconductor substrate;
• forming a plurality of line structures in the first semiconductor layer comprising:
• depositing a third semiconductor layer on the first semiconductor layer;
• etching the third semiconductor layer to create a plurality of line structures in the third semiconductor layer;
• depositing a fourth semiconductor layer on the plurality of line structures in the etched third semiconductor layer
• etching the fourth semiconductor layer to create a plurality of line structure in the fourth semiconductor layer;
• removing the plurality of line structures in the third semiconductor layer;
• depositing a fifth semiconductor layer on the plurality of line structures in the etched fourth semiconductor layer;
• etching the semiconductor fifth layer to create a plurality of line structures in the fifth semiconductor layer;
• removing the plurality of line structures in the fourth semiconductor layer;
• and
• using the plurality of line structures in the fifth semiconductor layer as a mask to etch first layer to form a plurality of line structures in the first semiconductor layer;
• using the plurality of line structure as a mask to etch the surface of the second semiconductor layer;
• and
• annealing the etched second semiconductor layer in a hydrogen atmosphere to form the corrugated surface in the second semiconductor layer.