Patent ID: 7235984

Claim:
A probe device for inspecting electrical characteristics of an object W to be inspected, comprising: a mounting table for mounting thereon the object to be inspected, the mounting table being movable in X, Y, Z and θ directions; a probe card disposed above the mounting table and provided with a plurality of probes; and a contact load monitoring device including at least one displacement sensor and a control device and monitoring a contact load exerted on the mounting table by the probes during an overdriving stage, wherein the displacement sensor is disposed in a space below the mounting table and measures, as an amount of sinking, a displacement of a reference surface at a bottom side of the mounting table caused by the contact load exerted on the mounting table by the probes during the overdriving stage; wherein the control device is provided with a correlation table for amounts of sinking of the reference surface of the mounting table and contact loads and estimates a contact load by using the displacement measured by the displacement sensor and the correlation table; and wherein the control device adjusts the contact load to be identical with a designed contact load by further elevating the mounting table in case the contact load is less than the designed contact load.