Solar wafers are used in the production of solar cells, which generate
electricity from sunlight.
The four-point probe method is a precise technique used in the
electronics industry to measure the resistivity of semiconductor materials in solar and other wafers.
By employing four precisely spaced probes on the
wafer surface, it passes a known current through the outer probes while
measuring the resulting voltage with the inner probes. These measurements are crucial in evaluating the quality of the semiconductor material, they include:
1. Sheet Resistance: This measures the resistance of the material per
square. Lower sheet resistance indicates better conductivity, which is
important for efficient energy conversion in solar cells.
2. Carrier Concentration and Mobility: By analyzing the voltage and
current characteristics of the material, one can determine the
concentration of charge carriers (electrons or holes) and their mobility
within the material.
Ensuring optimal efficiency and performance in the production of solar cells,
the technique’s non-destructive nature makes it a valuable tool in quality
control and research within solar technology.
MPP’s industry leading four point probes are designed and manufactured
to provide clear advantages for probing solar wafers, such as:
• “On the fly” needle force adjustment
• Low force variation between needles
• A wide range of needle tip radii and spacings– supporting a wide
range of wafer types
• Ruby guides for minimal measurement hysteresis