Einsatz flexibler kapazitiver Drucksensoren in intelligenten Implantaten

摘要

Pressure sensor implants for wireless monitoring of heart failure or hypertension patients can show strong signal fluctuations due to mechanical stress during fabrication or implantation into the body when there is inadequate design of the assembly and interconnection technology. This is due to the high sensitivity of the capacitive silicon membranes both to changes in ambient pressure as well as to mechanical stresses in the underlying chip substrate. A silicon sensor can become flexible and jointed by thinning it down to a few hundredths of a millimeter and inserting trench structures by plasma etching that define areas of greatest strain off the pressure-sensitive membranes. These measures reduce and can even completely eliminate the sensitivity of the membrane structures on undesirableeffects.