Process for production of soi substrate and process for production of semiconductor device

A method for manufacturing a semiconductor device comprising the steps of:

• selectively forming a porous layer in a single-crystal semiconductor substrate;
• forming a first oxide layer on surfaces of the single-crystal semiconductor substrate and the porous layer;
• adding hydrogen into the single-crystal semiconductor substrate and the porous layer through the first oxide layer, thereby forming a hydrogen-added layer in the single-crystal semiconductor substrate and the porous layer;
• adhering the single-crystal semiconductor substrate and a supporting substrate having a second oxide layer with the first oxide layer and the second oxide layer interposed therebetween;
• performing a heat treatment, thereby separating the single-crystal semiconductor substrate and the porous layer along the hydrogen-added layer;
• and
• removing the porous layer over the supporting substrate.

A method for manufacturing a semiconductor device comprising the steps of:

• selectively forming a porous layer in a single-crystal semiconductor substrate;
• forming a first oxide layer on the single-crystal semiconductor substrate and the porous layer;
• adding hydrogen into the single-crystal semiconductor substrate and the porous layer through the first oxide layer, thereby forming a hydrogen-added layer in the single-crystal semiconductor substrate and the porous layer;
• adhering the single-crystal semiconductor substrate and a supporting substrate having a second oxide layer with the first oxide layer and the second oxide layer interposed therebetween;
• performing a first heat treatment, thereby separating the single-crystal semiconductor substrate and the porous layer along the hydrogen-added layer;
• performing a second heat treatment on the supporting substrate;
• and
• removing the porous layer over the supporting substrate.

A method for manufacturing a semiconductor device comprising the steps of:

• selectively forming a porous layer in a single-crystal semiconductor substrate;
• forming a first oxide layer on the single-crystal semiconductor substrate and the porous layer;
• flattening a surface of the first oxide layer;
• adding hydrogen into the single-crystal semiconductor substrate and the porous layer through the flattened first oxide layer, thereby forming a hydrogen-added layer in the single-crystal semiconductor substrate and the porous layer;
• adhering the single-crystal semiconductor substrate and a supporting substrate having a second oxide layer with the first oxide layer and the second oxide layer interposed therebetween;
• performing a heat treatment, thereby separating the single-crystal semiconductor substrate and the porous layer along the hydrogen-added layer;
• and
• removing the porous layer over the supporting substrate.

A method for manufacturing a semiconductor device comprising the steps of:

• selectively forming a porous layer in a single-crystal semiconductor substrate;
• forming a first oxide layer on the single-crystal semiconductor substrate and the porous layer;
• adding hydrogen into the single-crystal semiconductor substrate and the porous layer through the first oxide layer, thereby forming a hydrogen-added layer in the single-crystal semiconductor substrate and the porous layer;
• adhering the single-crystal semiconductor substrate and a supporting substrate having a second oxide layer with the first oxide layer and the second oxide layer interposed therebetween;
• performing a heat treatment, thereby separating the single-crystal semiconductor substrate and the porous layer along the hydrogen-added layer;
• removing the porous layer over the supporting substrate, thereby forming at least one island-like single-crystal semiconductor layer over the supporting substrate;
• forming a gate electrode over the island-like single-crystal semiconductor layer with a gate insulating film interposed therebetween;
• and
• introducing a p-type or an n-type impurity into the island-like single-crystal semiconductor layer to form at least a source region, a drain region and a channel forming region between the source region and the drain region.