A study of the effect of 1- and 12-MeV electron and Co60 γ irradiation has been made on power p-i- n diodes and Schottky barrier diodes fabricated on the same starting material. A comparison of the results from these two types of structures illustrated the influence of device processing on the type of defects formed by subsequent irradiation. Detailed electrical characterization of the defects demonstrated good consistency between certain elements of the structural nature of the defect, inferred from these measurements, and those already obtained from electron spin resonance (ESR) measurements. Lifetime measurements on the p-i-n diodes indicated that both the A center and the divacancy were active recombination centers. Finally, data are presented on defect and lifetime annealing.

Abstract-A 402-405 MHz MICS band transceiver has been developed for implantable medical applications. The transceiver offers exceptionally low power consumption whilst providing a high data rate. The circuit features a unique ultra low power wakeup system enabling an average sleep current of less than 250 nA. The transmit and receive current is less than 5 mA when operating at a data rate of up to 800 kbps. System integration is high and only 3 external components (crystal and 2 decoupling capacitors) and a matching network are required. The transceiver can also operate in the 433 MHz ISM band. The key system design features and performance of this transceiver are presented in this paper.

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Iron has been diffused into p- and n-type silicon containing various concentrations of carbon and oxygen. Apart from the established iron interstitial level and the iron-boron complex, no new centers were detected involving iron complexing with either the carbon or the oxygen. The iron-boron level was shown to dissociate by a recombination-enhanced mechanism and a deep acceptor level of this complex was detected at Ec −0.29 eV, which must be the recombination level rather than the well-established level at Ev +0.1 eV.

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Electron paramagnetic resonance (EPR) and diode capacitance measurements, including deep level transient spectroscopy (DLTS), have been used to identify the levels in the silicon band gap associated with the Au-Fe complex. Two deep levels at Ee -0.354 eV and Ev + 0.434 eV were found with properties consistent with those of the complex; the role of gold in the formation of the complex was confirmed by the observation that during low-temperature annealing ( < 350°C) the changes in the concentration of the center were accompanied by equal and opposite changes in the concentration of the normal gold acceptor and donor levels. PACS numbers: 71.55.Fr 952 J. Appl. Phys. 55 (4). 15 February 1984

The first results obtained using a SO1 device for microdosimetry applications are presented. Microbeam and broadbeam spectroscopy methods are used for determining minority carrier lifetime and radiation damage constants. A spectroscopy model is presented which includes the majority of effects that impact spectral resolution. Charge collection statistics were found to substantially affect spectral resolution. Lateral diffusion effects significantly complicate charge collection.

Reverse-biased silicon p-n junction arrays using Silicon-On-Insulator technology have been proposed as microdosimeters. The performance of such detectors in boron neutron capture therapy (BNCT) is discussed. This work provides the first reported measurements using boron-coated silicon diode arrays as microdosimeters in BNCT. Results are in good agreement with measurements with gas proportional counters. Various boron-coating options are investigated along with device orientation effects. Finally, a 235U coating is tested to simulate the behavior of the device in a heavy-ion therapy beam.