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

A method of forming a micro-mechanical pressure sensor comprising the steps of:

• providing a first substrate,
• depositing a first masking layer on the first substrate,
• patterning the first masking layer on a front side of the first substrate,
• etching a cavity on the front side of the first substrate,
• removing the first masking layer from the first substrate,
• forming a bulk layer in the front side of the first substrate,
• depositing a second masking layer on the bulk layer,
• patterning the second masking layer on the back side of the first substrate to form an opening,
• etching a second cavity on the back side of the first substrate, thereby forming a diaphragm in the first substrate,
• removing the second masking layer from the first substrate,
• depositing a conductive layer on the front side of the first substrate to provide a highly conductive diaphragm,
• providing a second substrate formed from a plurality of dielectric layers and a plurality of conductive layers forming an inductive coil,
• polishing the front side of the second substrate to achieve a smooth surface,
• depositing a second conductive layer on the front side of the second substrate,
• patterning the second conductive layer to form a counter electrode and a bonding area, and
• bonding the first and second substrates together to form an air gap between the conductive diaphragm and the counter electrode.