Controlled nanoscale doping of semiconductors via molecular monolayers.
One of the major challenges towards scaling electronic devices to the nanometre-size regime is attaining controlled doping of semiconductor materials with atomic accuracy, as at such small scales, the various existing technologies suffer from a number of setbacks. Here, we present a novel strategy for controlled, nanoscale doping of semiconductor materials by taking advantage of the crystalline nature of silicon and its rich, self-limiting surface reaction properties. Our method relies on the formation of a highly uniform and covalently bonded monolayer of dopant-containing molecules, which enables deterministic positioning of dopant atoms on the Si surfaces. In a subsequent annealing step, the dopant atoms are diffused into the Si lattice to attain the desired doping profile. We show the versatility of our approach through controlled p- and n-doping of a wide range of semiconductor materials, including ultrathin silicon-on-insulator substrates and nanowires, which are then configured into novel transistor structures.
Ho
Johnny C
JC
Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, Berkeley, California 94720, USA.
Yerushalmi
Roie
R
Jacobson
Zachery A
ZA
Fan
Zhiyong
Z
Alley
Robert L
RL
Javey
Ali
A