A pressure sensor, comprising: a substrate having a measuring membrane, and an electrically conductive cover layer, which has electrical contact elements and is electrically isolated from the substrate by an insulating layer. The cover layer is divided in such a manner that two independent measurements of the respective resistance between two contact elements are possible in two regions electrically isolated from one another. The regions of the cover layer serve to shield external electromagnetic influences from the sensor elements of the measuring membrane, to detect damage to the measuring membrane, as well as for determining exact temperature.

A cylindrical quartz crystal transducer that exhibits a low probability of twinning, and uses a combination of resonator signal inputs at the B-mode and C-mode frequencies to calculate resonator temperature. Crystallographic orientations are disclosed where combinations of B-mode and C-mode resonant frequencies exist that are sufficiently independent of pressure to enable accurate calculation of temperature under transient conditions. Such a transducer is usable at higher pressures and temperatures than conventional quartz pressure transducers. Furthermore, because the structure allows a choice of crystallographic orientation, other characteristics of the transducer, such as increased pressure sensitivity and activity dip-free operation, may be optimized by varying crystallographic orientation.

According to various embodiments, a dynamic pressure sensor includes a substrate, a reference volume formed in the substrate, a deflectable membrane sealing the reference volume, a deflection sensing element coupled to the membrane and configured to measure a deflection of the membrane, and a ventilation hole configured to equalize an absolute pressure inside the reference volume with an absolute ambient pressure outside the reference volume.

A physical quantity sensor includes a semiconductor substrate, a diaphragm section that is disposed on the semiconductor substrate and is flexurally deformed when receiving pressure, a sensor element that is disposed on the diaphragm section, an element-periphery structure member that is disposed on one surface side of the semiconductor substrate and forms a cavity section together with the diaphragm section, and a semiconductor circuit that is provided on the same surface side as the element-periphery structure member of the semiconductor substrate.