Current flow between neighbouring trench cells triggered by alpha particle strikes

The track of an alpha particle that traverses two adjacent trench-type memory cells acts as a conductive channel because of the high concentration of generated carriers so that, where the hit cells have different potential levels, a current flow is triggered which leads to an additional charge collection. The process of charge transfer between the cells owing to alpha particle striking is described by an equivalent circuit, which allows rapid calculation of the current through the parasitic channel, taking into account the total angle and energy spectrum of alpha particle radiation. It is found that the collected charge is appreciably increased only when the trench distance is comparable to the width of the p-n spacecharge region of the cell at high-level potential and when the alpha particle tracks run approximately parallel to the semiconductor surface