Ultra low voltage probing by time resolved emission (TRE) technology below 1.0V is very challenging for micro-processor debug in practical operation condition. This is because the photo-emission rate reduces exponentially as the power supply voltage decreases. In this paper, a novel technology with improved detector in solid immersion lens (SIL) TRE system was demonstrated for low voltage and small node probing. An improved detecting scheme was developed to collect 30% more photon detection efficiency than the previous system. The SIL TRE with low dark noise detector technology has been successfully applied to optical probing for 45nm product debug. The performance gain improvement in strong and weak signal regime has been demonstrated against the current detector technology. It has also demonstrated the capability on probing the ultra low voltage at 0.75 V for sub micron node of 45nm process.