Research on Instrument for Testing Sheet Resistance Without Testing Pattern and the Orientation of Probes
无测试图形薄层电阻测试仪及探针定位

A new type of instrument for testing sheet resistance of ULSI wafers by an inclined four-point square probe is introduced.It can be used in the measurement of resistivity uniformity for a wafer specimen without testing pattern.The probes are observed on the display of a computer by a microscope and a head of pickup camera.The testing location of the probes and specimen table is regulated by the way of program control and servo engines.The affection upon measuring results arising from the wander of probes is also discussed and the calculating equation is deduced.The distributing graphs arising from the wander of probes are drawn in theory calculating and in practical testing.A wafer specimen of four inches is measured with the equipment and an equal-value line Mapping graph is drawn.