Trench capacitor with an intrinsically balanced field across the dielectric

摘要: The preferred embodiment of the present invention provides an improved capacitor design that overcomes many limitations prior art. uses germanium to adjust work function storage node. Specifically, addition modifies fermi level node, moving towards conduction band. This modification reduces difference in band-edge potentials between node and counter electrode, thus reducing maximum electric potential seen across capacitor. In embodiment, p-type doped silicon is formed trench adjacent dielectric layer. A barrier layer then over germanium, remaining area filled with n+-type polysilicon. adjusts workfunction toward minimizes buried plate, which serves as electrode. has effect balancing for stored high low situations. dielectric. solution improves reliability capacitor, especially those capacitors relatively thin layers, without requiring additional circuitry bias increasing power consumption. also leakage current through dielectric, signal retention time.