A MEMS element , comprising: a base constituted with a silicon substrate; a device layer electrically insulated from the base ; a fixed electrode and a movable electrode formed in the device layer ; the fixed electrode having a plurality of fixed comb teeth , a fixed electrode pad and a support fastening portion ; and the movable electrode having a plurality of movable comb teeth which are interdigitated with the fixed comb teeth , wherein: the support fastening portion includes a comb tooth linking portion that connects the plurality of fixed comb teeth ; and the base comprises an opening , wherein the fixed electrode and the movable electrode are at least in part disposed over the opening ; characterised in that the base comprises a projecting portion which projects from an edge of the opening and extends along the comb tooth linking portion , wherein a fastening portion is disposed at the end of the projecting portion ; wherein the end of the comb tooth linking portion is fixed to the fastening portion at the end of the projecting portion and a portion of the base , which would face opposite at least part of the comb tooth linking portion between the fastening portion and the fixed electrode pad , is removed, forming a gap between the projecting portion and the comb tooth linking portion . a base constituted with a silicon substrate; a device layer electrically insulated from the base ; a fixed electrode and a movable electrode formed in the device layer ; the fixed electrode having a plurality of fixed comb teeth , a fixed electrode pad and a support fastening portion ; and the movable electrode having a plurality of movable comb teeth which are interdigitated with the fixed comb teeth , wherein: the support fastening portion includes a comb tooth linking portion that connects the plurality of fixed comb teeth ; and the base comprises an opening , wherein the fixed electrode and the movable electrode are at least in part disposed over the opening ; characterised in that the base comprises a projecting portion which projects from an edge of the opening and extends along the comb tooth linking portion , wherein a fastening portion is disposed at the end of the projecting portion ; wherein the end of the comb tooth linking portion is fixed to the fastening portion at the end of the projecting portion and a portion of the base , which would face opposite at least part of the comb tooth linking portion between the fastening portion and the fixed electrode pad , is removed, forming a gap between the projecting portion and the comb tooth linking portion . the support fastening portion includes a comb tooth linking portion that connects the plurality of fixed comb teeth ; and the base comprises an opening , wherein the fixed electrode and the movable electrode are at least in part disposed over the opening ; characterised in that the base comprises a projecting portion which projects from an edge of the opening and extends along the comb tooth linking portion , wherein a fastening portion is disposed at the end of the projecting portion ; wherein the end of the comb tooth linking portion is fixed to the fastening portion at the end of the projecting portion and a portion of the base , which would face opposite at least part of the comb tooth linking portion between the fastening portion and the fixed electrode pad , is removed, forming a gap between the projecting portion and the comb tooth linking portion . <EOS>