PACKAGING OF PRESSURE MICROSENSORS FOR CLINICAL APPLICATIONS
Abstract (Summary)In this thesis, micromachining technologies are used to develop custom packages for pressure sensors in clinical applications. Silicon die pressure sensors were used for two clinical applications, namely the development of pressure micro-sensing catheters for neonatal care and pressure sensors for in vivo measurements on spinal growth plates. A pressure microsensing catheter for neonatal care has been developed to measure intravascular blood pressure. The design uses polymer flip-chip bonding on a flexible Kapton film for mounting silicon pressure micro-sensors into the 5 French dual lumen neonatal catheters (1.67 mm o.d.). While other groups have mounted MEMS sensors on guide wires, our dual-lumen approach permits one lumen of the catheter to contain a packaged pressure sensor while the other lumen retains the catheter functionality. The packaged sensors were characterized in nitrogen and water environments, both statically and dynamically. A new transducer system has been developed for in vivo measurement of pressure of spinal growth plates. A model has been previously proposed for correcting spinal deformities with a staple-like implant, and this sensor will be used in vivo to quantify the pressure that alters growth in this new model of deformity and treatment. The pressure sensor die was 0.65 mm3 and the overall packaged sensor size was 1.5 mm × 2.5 mm × 0.9 mm. The completed sensors were fully characterized by hydrostatic and compression tests, and performed linearly. The ruggedness and small package size will allow the sensor to be placed bilaterally in the annulus of porcine spinal intervertebral discs to record pressure for up to two months.
School:University of Cincinnati
School Location:USA - Ohio
Source Type:Master's Thesis
Date of Publication:01/01/2005