We demonstrate techniques for measuring thermoelectric voltages and generating on-chip power using a silicon-on-insulator substrate. Our design uses lateral heat conduction in the silicon overlayer to establish temperature gradients, which dramatically reduces microfabrication complexity compared to competing designs based on a free-standing membrane. This letter characterizes the thermoelectric power of a metal-semiconductor structure involving a doped SbTe alloy that is relevant for phase-change memory. The thermoelectric power of the SbTe-TiW thermocouple is 24 μV/K, and the power generation output achieves up to 0.56 μW/cm² with a temperature gradient of 18°K.