Diffusion of Acceptor Dopants in Atomically Precise Devices

Atomically precise (AP) electrical devices, fabricated using hydrogen depassivation lithography in a scanning tunneling microscope, offer a potential pathway to ultra-efficient transistors. Almost all previous work regarding AP devices has been focused on understanding the properties of phosphorus-based donor devices integrated into intrinsic or donor-implanted substrates. Equivalent knowledge for integration on to substrates having acceptor dopants is critically lacking. Here, we present our work in understanding the diffusion processes of acceptor dopants during CMOS compatible AP processing, which demonstrates highly counterintuitive behavior compared to donor dopants. We speculate on the origin of this diffusion mechanism, which is neither thermally-driven nor concentration gradient-driven.