Microelectromechanical microphones play a very important part in modern communication. They generally comprise a membrane displaceable by sound to be detected, the displacement of which membrane contains information about characteristics of the sound to be detected, such as, for instance, sound frequency or sound amplitude. The displacement of a membrane of a microelectromechanical microphone of this type can be read out capacitively, for example, wherein the membrane together with a reference electrode forms a capacitor, the capacitance of which changes as a result of a displacement of the membrane. A voltage or/and current change caused by a capacitance change of this type can be measured by a suitable read-out circuit, as a result of which characteristics of the sound to be detected are determinable.
During the production of microelectromechanical microphones, a major challenge generally consists in producing the reference electrode with a well-defined shape in order to be able to ensure a reproducible behavior. A major problem here results from mechanical stresses to which the reference electrode may be subjected and which can adversely affect a reproducible behavior. Said mechanical stresses may have intrinsic causes and be attributable to thermal or mechanical loads during the production process. Alternatively or additionally, mechanical stresses of this type may be attributable to mutually different coefficients of thermal expansion of different components of a microelectromechanical microphone, which may be transferred to the reference electrode.