Method of modifying the strain state of a semiconducting structure with stacked transistor channels

A method of modifying a strain state of a first channel structure in at least one first transistor, the first channel structure being formed from superposed semiconducting elements, the method comprising:

• a) providing at least one first semiconducting structure on a substrate, said structure being formed from a semiconducting stack comprising alternating elements based on at least one first semiconducting material and elements based on at least one second semiconducting material different from the at least one first semiconducting material;
• then
• b) removing portions of the at least one second semiconducting material from the at least one first semiconducting structure by selective etching, the removed portions of the at least one second semiconducting material forming at least one empty space;
• c) filling the at least one empty space with a dielectric material;
• d) forming a straining zone on the at least one first semiconducting structure based on a first strained material having an intrinsic strain;
• and
• e) performing thermal annealing to cause the dielectric material to creep, and to cause a change in a strain state of the elements based on the at least one first semiconducting material in the at least one first semiconducting structure.