The Effect of Magnetic Field on Readout of Diodes Used as NIEL Counters

Voltage measurement at a given forward current in dedicated dosimetric diodes is used to monitor displacement damage in silicon caused by energetic hadrons in the LHC experiments. The diodes operate in a strong magnetic field which influences their performance. In this work, measurements of the effect of the magnetic field on two types of devices: high sensitivity CMRP diodes and commercial BPW34F silicon p-i-n diodes are presented. Our results show that the magnetic field effects are manageable and will not significantly deteriorate the performance of the displacement damage measurements.