Abstract: This disclosure describes an elastic multi-contact probe that includes conductive strips each of which comprises a conductive elastomer; dielectric strips formed on a back surface of a respective conductive strip; and a layer of a thermoplastic formed on back surfaces of the dielectric strips. The disclosure also describes a method that includes measuring a first I-V curve between a pair of inner probes of the an elastic multi-contact probe based on a first current applied to a pair of outer probes; determining a first slope of a linear region of the first I-V curve; measuring a second I-V curve between the pair of inner probes based on a second current applied to the pair of inner probes; determining a second slope of a linear region of the second I-V curve; and calculating a sheet resistance and a contact resistivity of the semiconductor material based on the first and second slopes.

Abstract: This disclosure describes an elastic multi-contact probe that includes conductive strips each of which comprises a conductive elastomer; dielectric strips formed on a back surface of a respective conductive strip; and a layer of a thermoplastic formed on back surfaces of the dielectric strips. The disclosure also describes a method that includes measuring a first I-V curve between a pair of inner probes of the an elastic multi-contact probe based on a first current applied to a pair of outer probes; determining a first slope of a linear region of the first I-V curve; measuring a second I-V curve between the pair of inner probes based on a second current applied to the pair of inner probes; determining a second slope of a linear region of the second I-V curve; and calculating a sheet resistance and a contact resistivity of the semiconductor material based on the first and second slopes.

Abstract: Non-Contact measurement of characteristics of p-n junctions includes illuminating an illumination area of a surface of a p-n junction with light, measuring a first junction photovoltage (JPV) signal from a first area of the p-n junction with a first electrode, measuring a second JPV signal from a second area with a second electrode, measuring a third JPV signal from a third area with a reference electrode, and determining a sheet resistance of the p-n junction top layer with a corrected first JPV signal, a corrected second JPV signal, a corrected first calibration JPV signal, a corrected second calibration JPV signal or the known sheet resistance of the calibration p-n junction.

Abstract: Non-contact measurement of one or more electrical response characteristics of a p-n junction includes illuminating a surface of the p-n junction with light of a first intensity having a modulation or pulsed characteristic sufficient to establish a steady-state condition in a junction photovoltage (JPV) of the p-n junction, measuring a first JPV from the p-n junction within the illumination area, illuminating the surface of the p-n junction with light of an additional intensity, measuring an additional photovoltage from the portion of the p-n junction within the illumination area, determining a photocurrent density of the p-n junction at the first intensity. The non-contact measurement further includes determining the forward voltage, the saturation current density, the ideality factor or one or more I-V curves with the measured first photovoltage, the measured additional photovoltage and/or the determined photocurrent density of the p-n junction.

Abstract: Non-contact measurement of one or more electrical response characteristics of a LED structure includes illuminating an illumination area of a surface of a light emitting diode structure with one or more light pulses, measuring a transient of a luminescence signal from a luminescence area within the illumination area of the light emitting diode structure with a luminescence sensor, determining a first luminescence intensity at a first time of the measured transient of the luminescence signal from the light emitting diode structure, determining a second luminescence intensity at a second time different from the first time of the measured transient of the luminescence signal from the light emitting diode structure and determining an intensity of the electroluminescence component of the luminescence signal from the light emitting diode structure based on the first luminescence signal and the second luminescence signal.

Abstract: Methods and apparatus for providing measurements in p-n junctions and taking into account the lateral current for improved accuracy are disclosed. The lateral current may be controlled, allowing the spreading of the current to be reduced or substantially eliminated. Alternatively or additionally, the lateral current may be measured, allowing a more accurate normal current to be calculated by compensating for the measured spreading. In addition, the techniques utilized for controlling the lateral current and the techniques utilized for measuring the lateral current may also be implemented jointly.

Abstract: Non-Contact measurement of characteristics of p-n junctions includes illuminating an illumination area of a surface of a p-n junction with light, measuring a first junction photovoltage (JPV) signal from a first area of the p-n junction with a first electrode, measuring a second JPV signal from a second area with a second electrode, measuring a third JPV signal from a third area with a reference electrode, and determining a sheet resistance of the p-n junction top layer with a corrected first JPV signal, a corrected second JPV signal, a corrected first calibration JPV signal, a corrected second calibration JPV signal or the known sheet resistance of the calibration p-n junction.

Abstract: Non-contact measurement of one or more electrical response characteristics of a LED structure includes illuminating an illumination area of a surface of a light emitting diode structure with one or more light pulses, measuring a transient of a luminescence signal from a luminescence area within the illumination area of the light emitting diode structure with a luminescence sensor, determining a first luminescence intensity at a first time of the measured transient of the luminescence signal from the light emitting diode structure, determining a second luminescence intensity at a second time different from the first time of the measured transient of the luminescence signal from the light emitting diode structure and determining an intensity of the electroluminescence component of the luminescence signal from the light emitting diode structure based on the first luminescence signal and the second luminescence signal.

Abstract: Methods and apparatus for providing measurements in p-n junctions and taking into account the lateral current for improved accuracy are disclosed. The lateral current may be controlled, allowing the spreading of the current to be reduced or substantially eliminated. Alternatively or additionally, the lateral current may be measured, allowing a more accurate normal current to be calculated by compensating for the measured spreading. In addition, the techniques utilized for controlling the lateral current and the techniques utilized for measuring the lateral current may also be implemented jointly.

Abstract: Non-contact measurement of one or more electrical response characteristics of a p-n junction includes illuminating a surface of the p-n junction with light of a first intensity having a modulation or pulsed characteristic sufficient to establish a steady-state condition in a junction photovoltage (JPV) of the p-n junction, measuring a first JPV from the p-n junction within the illumination area, illuminating the surface of the p-n junction with light of an additional intensity, measuring an additional photovoltage from the portion of the p-n junction within the illumination area, determining a photocurrent density of the p-n junction at the first intensity. The non-contact measurement further includes determining the forward voltage, the saturation current density, the ideality factor or one or more I-V curves with the measured first photovoltage, the measured additional photovoltage and/or the determined photocurrent density of the p-n junction.