a method and system for detecting or reviewing defective contacts on a semiconductor device are disclosed . in a first embodiment , the method and system comprise providing a positive charge sufficient enough to turn on a gate of an associated mos device and scanning an area of interest within the mos device with a primary electron beam of proper landing energy to generate image . the method and system include analyzing the signal of contacts and identify the open contacts . in a second embodiment , the method and system comprises pre - scanning or irradiating the wafer surface defect with an accessory beam , a plurality of times , to achieve positive charged / sufficient to turn on the gate on the associated mos devices of the wafer ; and scanning the at least a portion of the device circuits with a primary electron beam of proper landing energy to generate images wafer or area of interest . the method and system include analyzing the signal and / or image of contacts and identify the open contacts .