NONUNIQUENESS OF TIME-DEPENDENT-DIELECTRIC-BREAKDOWN DISTRIBUTIONS

The time-dependent-dielectric-breakdown (TDDB) distributions measured on a series of identical oxides at the same voltages have been shown t o depend on the resistance and capacitance of the measurement test equ ipment. The TDDB distributions were shifted to shorter times if the im pedance of the test equipment was lowered and/or the capacitance of th e test equipment was raised, The lower resistances and higher capacita nces allowed the nonshorting early electric breakdowns to develop into shorting, thermal, dielectric breakdowns. (C) 1997 American Institute of Physics. [S0003-6951(97)02451-0].