Confinement effects on phosphorus donors embedded in silicon nanocrystals

Magnetic resonance of shallow donor center phosphorus is used to track size -related changes of energy band structure in silicon powders. Small conduct ion band upshifts of several meV are determined for nanocrystals of approxi mately d = 100 nm diameter and smaller. These are interpreted as the onset of the quantum confinement-induced variations of silicon band structure. Th e conduction band upshift is experimentally found to follow the 1/d(1.2) de pendence in the investigated size range. (C) 1999 Elsevier Science B.V. All rights reserved.