The invention relates to a semiconductor structure, including:a semiconductor layer, including a membrane suspended above a carrier layer, the suspended membrane being formed of a central section, which is tensilely stressed and of a plurality of tensioning arms; andleast one optical cavity, bounded by two optical reflectors, which are placed in the lateral sections on either side of the central section;wherein:the central section is designed to transmit in the direction of the optical reflectors at least one uneven-order mode; andeach of said optical reflectors is formed of two lateral half-reflectors, which are arranged on either side of a longitudinal axis of the lateral section, so as to at least partially reflect said uneven-order mode.