Copper transport in thermal SiO2

The transport of copper in silicon dioxide thermally grown on single crystalline silicon was studied by capacitance techniques, secondary ion mass spectroscopy (SIMS) analysis, and Rutherford backscattering spectrometry (RBS). Metal/oxide/silicon (MOS) capacitors were used to study the penetration of copper into the oxide as a function of temperature and applied electric field. The role of a titanium layer between the copper and the oxide was also studied. Bias-thermal stress (BTS) studies of MOS structures were conducted at 150 o C to 300 o C with an electric field of 1 MV/cm for times ranging between 10 min and 168 h