Dynamic random access memory i.e. checkerboard trench dynamic random access memory, for semiconductor industry, has transistors provided in substrate, where depth of source of each transistor differs from depth of drain of each transistor

摘要

The memory (20) has an active region and a set of gate conductors provided on a silicon substrate (22), and a set of deep trench capacitors. Each deep trench capacitor is arranged in the silicon substrate at respective intersection points of the gate conductors and the active region. A set of vertical transistors (66) is provided in the silicon substrate. Each vertical transistor has a source (64) in a side of a gate (43) and a drain (54) in other side of the gate, where a depth of the source differs from a depth of the drain.