Editing Precision Thermocouple Based Temperature Measurement System (section)

=== 5.1. Interpretation of the Output Voltage Response ===

The output voltage remains consistently negative across all temperature differences and all four measurement runs, indicating a stable thermoelectric response characteristic of n-type ZnO. Importantly, no polarity reversals are observed, suggesting that the measured signal is not affected by contact instability or measurement drift during thermal cycling.
In addition to this consistent polarity, the data exhibits a nearly ΔT-independent voltage offset in the microvolt range. Since this component does not scale with the applied temperature difference, it is not part of the Seebeck response and likely arises from systematic contributions in the measurement loop, such as metal–semiconductor contact potentials. Because this offset remains essentially constant, it does not affect the slope-based extraction of the Seebeck coefficient.
Despite repeated reapplication of contacts between runs, the temperature-dependent trend remains reproducible, indicating that the thermoelectric sensitivity is governed by the bulk response of the ZnO pellet, while variations between runs are largely confined to the baseline voltage level rather than the ΔT-dependent behaviour