Patent ID: 6529021
Filing Date: 2003-03-04
Classification: G01R

Abstract:
A buckling beam contactor for contacting an array of pads positioned on a device under test, comprising:an upper, an offset and a lower plate with holes therein, each of the plates being distally separated from the next plate by a spacer, wherein the distance that separates the bottom of the offset plate and the top of the lower plate determines a critical buckling force that is dependent on a critical buckle length LCR separating the offset plate from the lower plate, LCR being determined by the equation: LCR=[(N p2 E I)/PCR]Â½â€ƒwherein N is a coefficient dependent on end conditions of the wire, E is a modulus of elasticity of the probe material, I represents a moment of inertia of the probe, and PCR is a critical force that buckles a long wire; and an array of flexible wires positioned transversally to the plates, wherein each of the flexible wires cross a corresponding hole in the upper, offset and lower plates, each wire respectively contacting a pad of the device under test, wherein by shifting the center of the hole of the lower plate relative to the center of the offset plate, the tip of the wire exiting from the lower plate at an angle with respect to the plane formed by the pads of the device under test provides a controlling wiping movement.