Laser stimulation with 1300nm as thermal (TLS) and with 1064nm as photoelectric (PLS) laser stimulation techniques are now widely used in failure analysis of Integrated Circuits. The stimulation signatures when using a 1064nm laser are often a combination of PLS and TLS along with laser induced impact ionization. The results show the existence of laser induce impact ionization current component when high laser power is applied. This work presents a quantitative investigation of 1064nm laser stimulation effects on single NMOSFET devices. For high laser power applications the impact ionization current becomes the dominant component for 1064nm laser stimulation.