Contact electrification was demonstrated on Si (100) wafer, and surface charge images at submicron scale were analysed using Kelvin force microscopy (KFM). Potential map images have shown carpet-like patterns on the (100) plane of Si wafer. Individual potential spikes that appeared on the surface are indicative of the presence of charges arising from contact electrification. It was clearly shown that positive and negative surface potential maps on Si (100) wafer with low resistivity have minimal change in the order of ±2.5 mV after 4800 seconds of noncontact electrification. The mechanism for the slow discharged on the Si (100) wafer can be modelled like a clamped capacitor direct current (D.C.) electric circuit.