A method for manufacturing a microelectronic device comprising a membrane suspended over at least one final cavity , the method comprising: • providing a support substrate comprising a superficial layer having a first face , • forming at least one elementary cavity in the superficial layer of the support substrate , the at least one elementary cavity opening at said first face , and • providing a donor substrate having a first face , then • forming at least one membrane suspended over at least one final cavity , forming the membrane comprising: ∘ assembling the support substrate and the donor substrate by joining the first face of the support substrate to the first face of the donor substrate , so that the donor substrate covers at least partially the at least one elementary cavity , then ∘ thinning the donor substrate so as to form the membrane , characterised in that the method further comprises: • before or after forming the membrane , forming at least one anchoring pillar of the membrane , the at least one anchoring pillar being: ∘ based on at least one material different from a material forming the superficial layer , and ∘ configured to support at least one lower face of the membrane , at least at an edge of the membrane , and • after forming the at least one anchoring pillar , and after assembly, etching the superficial layer of the support substrate so as to enlarge the at least one elementary cavity , according to at least one direction parallel to a main plane of extension (x, y) of the first face of the superficial layer of the support substrate , to form the final cavity , said etching being configured so as to selectively etch the superficial layer with respect to the at least one material of the at least one anchoring pillar . • providing a support substrate comprising a superficial layer having a first face , • forming at least one elementary cavity in the superficial layer of the support substrate , the at least one elementary cavity opening at said first face , and • providing a donor substrate having a first face , then • forming at least one membrane suspended over at least one final cavity , forming the membrane comprising: ∘ assembling the support substrate and the donor substrate by joining the first face of the support substrate to the first face of the donor substrate , so that the donor substrate covers at least partially the at least one elementary cavity , then ∘ thinning the donor substrate so as to form the membrane , ∘ assembling the support substrate and the donor substrate by joining the first face of the support substrate to the first face of the donor substrate , so that the donor substrate covers at least partially the at least one elementary cavity , then ∘ thinning the donor substrate so as to form the membrane , • before or after forming the membrane , forming at least one anchoring pillar of the membrane , the at least one anchoring pillar being: ∘ based on at least one material different from a material forming the superficial layer , and ∘ configured to support at least one lower face of the membrane , at least at an edge of the membrane , and ∘ based on at least one material different from a material forming the superficial layer , and ∘ configured to support at least one lower face of the membrane , at least at an edge of the membrane , and • after forming the at least one anchoring pillar , and after assembly, etching the superficial layer of the support substrate so as to enlarge the at least one elementary cavity , according to at least one direction parallel to a main plane of extension (x, y) of the first face of the superficial layer of the support substrate , to form the final cavity , said etching being configured so as to selectively etch the superficial layer with respect to the at least one material of the at least one anchoring pillar . <EOS>