Characterization of ULSI gate oxide reliability using substrate and channel electron injection stresses

A hot electron reliability characterization methodology has been developed to separate the geometry and process related degradations using BIMOS (bipolar-MOS) and SMOSC (sourced MOS capacitor) tests structures which uniformly inject the hot electrons from the substrate into the oxide. In both test structures, the gate oxide current is independently controlled from the oxide electric field. The uniform injection into the gate oxide obtained in the BiMOS DC and the SMOSC AC (pulsed) substrate injection techniques facilitates rapid evaluation of gate oxide quality in the manufacturing environment independent of the drain doping profile