Gate-all-around transistors with hybrid orientation

A method for making a semiconductor device, the method comprising:

• bonding a first wafer including a first silicon substrate having a first crystallographic orientation to a second wafer including a second silicon substrate having a second crystallographic orientation;
• removing the second silicon substrate;
• removing a portion of a stack of alternating silicon layers and silicon germanium layers from the second wafer, wherein each of the silicon layers has the second crystallographic orientation;
• and
• forming a further stack of alternating further silicon layers and further silicon germanium layers on the first wafer, wherein each of the further silicon layers has the first crystallographic orientation.

A method of forming a semiconductor device, the method comprising:

• forming a p-type field-effect transistor including channels having a first crystallographic orientation on a first wafer;
• and
• forming an n-type field-effect transistor including channels having a second crystallographic orientation on the first wafer, wherein:
• the first crystallographic orientation is different than the second crystallographic orientation;
• and
• forming the p-type field-effect transistor and forming the n-type field-effect transistor includes forming a gate surrounding the channels having the first crystallographic orientation and the channels having the second crystallographic orientation.