Dead Layers in Charged-Particle Detectors

This paper presents the results of dead-layer thickness measurements on silicon surface-barrier and ion-implanted detectors and a comparison of various methods for measuring dead-layer thicknesses. Our experimental arrangement and estimates of experimental error are discussed. Data on dead-layer thicknesses of n-type and p-type surface-barrier detectors and boron-implanted position-sensitive detectors are given. A linear relation was observed between the dead-layer thickness and the metal electrode thickness for both the rectifying and ohmic contact of barrier detectors. The thinnest dead layers measured were 270Å (silicon equivalent) for 15 μg/cm2 of gold and 460Å (silicon equivalent) for 6 μg/cm2 of aluminum.