Atomistic Understanding of a Single Gated Dopant Atom in a MOSFET

Current semiconductor devices have been scaled to such dimensions that we need take an atomistic approach to understand their characteristics. The atomistic nature of these devices provides us with a tool to study the physics of very small ensembles of dopants right up to the limit of a single atom. Control and understanding of a dopants wavefunction and its coupling to the environment in a nanostructure could proof a key ingredient for device technology beyondCMOS. Here, we will discuss the eigenlevels and transport characteristics a single gated As donor. These donors are incorporated in the channel of a wrap-around gate transistors (FinFET). The measured level spectrum is shown to consist of levels associated with the donors Coulomb potential, levels associated with a triangular well at the gate interface and hybridized combinations of the two. The level spectrum of this system can be well described by a NEMO3D model, which is based on a numerical tight-binding approximation.