A Test Circuit for Statistical Evaluation of $p-n$ Junction Leakage Current and its Noise

We develop a test circuit to evaluate statistical distributions of p-n junction leakage currents for numerous samples in a very short time (0.1-10 fA, 28672 n⁺-p diodes in 0.77s). This test circuit is based on a complementary metal-oxide-semiconductor active pixel image sensor, which contains a current-to-voltage conversion function by a capacitor and amplifiers of voltage signals in each pixel. The test structure can be easily designed because of a small number of mask layer requirements (at least one poly-Si, one metal interconnect layer). Its simplicity has considerable benefits, such as an easy fabrication for the evaluation of various processes technologies without exceptional cares. We demonstrate that two normal distributions exist in the steady-state (time averaging) I_leak distributions, which have differing temperature dependencies. A distribution of the activation energy extracted from temperature dependence of I_leak is also revealed experimentally. Dynamic fluctuation of I_leak is confirmed to be measured, due to the execute pseudoparallel sampling among whole samples over a long recording time.