Micro-mechanical capacitive inductive sensor for wireless detection of relative or absolute pressure

A micro-mechanical pressure sensor comprising:

• a first substrate including a pressure sensitive diaphragm,
• a conductive layer formed on the diaphragm,
• a second hybrid substrate including a plurality of layers,
• an electrical inductor formed within the plurality of layers,
• a fixed counter electrode formed on top of the second substrate,
• the first and second substrates being bonded together and hermetically sealed to form a cavity between the fixed counter electrode and the conductive layer formed on the diaphragm, whereby the counter electrode and the conductive layer formed on the diaphragm form a capacitive structure,
• at least one first via connecting the electrical inductor to the fixed electrode, and
• at least one second via connecting the electrical inductor to the conductive layer on the diaphragm,
• wherein deflections of the diaphragm in response to a pressure differential between the sealed cavity and the exterior atmosphere results in a change of capacitance between the fixed counter electrode and the conductive layer on the diaphragm, and
• wherein the capacitive structure and the electrical inductor form an LC circuit, the resonant frequency of which may be detected by imposing an electromagnetic field on the capacitive structure.