Techniques are disclosed for forming a non-planar quantum well structure. In particular, the quantum well structure can be implemented with group IV or III-V semiconductor materials and includes a fin structure. In one example case, a non-planar quantum well device is provided, which includes a quantum well structure having a substrate (e.g. SiGe or GaAs buffer on silicon), a IV or III-V material barrier layer (e.g., SiGe or GaAs or AlGaAs), and a quantum well layer. A fin structure is formed in the quantum well structure, and an interfacial layer provided over the fin structure. A gate metal can be deposited across the fin structure. Drain/source regions can be formed at respective ends of the fin structure.