Reduced Volume Capacitor for In Vivo Defibrillator

Over one-third the volume of in-the-body heart defibrillators is devoted to the capacitor, whichconsumes approximately 20 cm3; this volume could be reduced to less than 1 cm3 using provenintegrated circuit technology. Employing metalorganic chemical vapor deposition (MOCVD), we will formthin film ceramic capacitors having at least a hundred times greater energy density than is presentlyavailable from commercial products. MOCVD makes this possible by eliminating the voids and other fieldenhancing defects which limit capacitor performance. Our capacitors will be barium-strontium-titanate-based and will feature extremely high dielectric constant (over 1,000) and breakdown strength (100V/micromoles). In Phase I, a single-layer 1 mu F, 1000 V capacitor will be fabricated and demonstratedas proof-of-principle that full-sized prototype capacitors can be built in Phase Il, where they would bemade available to manufacturers of defibrillators for testing. Successful completion of this program willlead to immediate introduction of smaller devices with improved patient comfort.