High-speed CMOS circuit testing by 50 ps time-resolved luminescence measurements

Noninvasive characterization of CMOS ring oscillators with 50 ps resolution is obtained by exploiting the broad-band infrared emission from switching transistors. A fast silicon single-photon avalanche-diode (SPAD) is used to attain high sensitivity and time resolution. Switching transitions of both nand p-channel MOSFETs are measured and the main features in the circuit operation are characterized. Systematic variations and increased jitter of switching transitions due to phase noise are accurately measured.