Geometry dependence of the energy levels in silicon isolated double quantum-dots

We present the fabrication and low-temperature electron transport measurements of circuits consisting of a single-island single-electron transistor monitoring an isolated double quantum-dot for a range of devices with different double quantum-dot geometries. Devices are fabricated in highly doped silicon-on-insulator, using electron beam lithography and reactive ion etching resulting in 'trench isolated' circuit elements that are capacitively coupled. We observe polarization of the isolated double quantum-dots as a function of the side gate potentials through changes in the single-electron transistor conduction characteristics. Polarization characteristics are seen to vary systematically with double quantum-dot geometry, which is attributed to the energy level structure of the isolated double quantum dot.