Charge collection within well-defined microstructures induced by the nuclear interaction of high-energy protons

Protons and heavy ions were each used to generate charges (electron-hole pairs) within or nearby the sensitive volumes of different microelectronic test structures. Charge collection was measured in fully depleted (Surface Barrier Detectors-YAG444 photodiode) as well as partially depleted (N-, N- + N+ GaAs Fat FET and UV100, YAG444 photodiodes) in junctions. The proton data were used to test the predictions of the CUPID code for fully and partially depleted devices. Enhanced charge collection at the edges of MESFET gates in GaAs were studied for different LET particles. A nearly linear relationship was found between the charge collection and the LET of the incident ions. The linear relationship is significant because it supports the assumption that one thickness can be used for the sensitive volume over a range of LET values. The effect of the surrounding material on charge generation within a well-defined volume was studied and founded to be small, for the dimensions studied