Specific Process Knowledge/Characterization/Four-Point Probe: Difference between revisions
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Sheet Resistivity = Sheet Resistance = Surface Resistivity = Surface Resistance | Sheet Resistivity = Sheet Resistance = Surface Resistivity = Surface Resistance | ||
''Limits of Measurement Capability'' | |||
1. The material must be capable of being probed, i.e. the probes must be able to make ohmic contact with the material e.g. Germanium, Silicon and metals. Materials such as Gallium Arsenide cannot normally be probed unless it is doped and measured with special measuring techniques such as that in the Four Dimensions Inc. GaAs probe. | 1. The material must be capable of being probed, i.e. the probes must be able to make ohmic contact with the material e.g. Germanium, Silicon and metals. Materials such as Gallium Arsenide cannot normally be probed unless it is doped and measured with special measuring techniques such as that in the Four Dimensions Inc. GaAs probe. | ||
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3. High resistivity material e.g. ion-implanted Silicon wafer, silicon on sapphire, can be measured using very low current (about 1uA or less) and trying to avoid a greater voltage indication than 200mV. Probably sheet resistance up to 107 ohms/square can be measured. | 3. High resistivity material e.g. ion-implanted Silicon wafer, silicon on sapphire, can be measured using very low current (about 1uA or less) and trying to avoid a greater voltage indication than 200mV. Probably sheet resistance up to 107 ohms/square can be measured. | ||