Heavy Cr doping of ZnSe by molecular beam epitaxy

• DOI: 10.1007/s11664-002-0234-0
• Publication Date: 2007-04-16T09:30:34Z
• Authors: B. L. Vanmil; A. J. Ptak; L. Bai; Lijun Wang; M. Chirila; N. C. Giles; T. H. Myers; Larry Wang
• Keywords: 02 engineering and technology; 0210 nano-technology

Epitaxial ZnSe layers were grown by molecular beam epitaxy (MBE) to study Cr incorporation with the long-term goal of demonstrating an alternate route for achieving transition-metal-doped lasers. Concentrations between 1015 atoms cm-3 and 4 × 1020 atoms cm-3 were achieved. Secondary ion-mass spectroscopy (SIMS) concentration profiles strongly suggest that surface segregation and accumulation of Cr occurs during growth. Photoluminescence (PL) measurements indicate Cr is incorporated in the optically active Cr2+ state up to levels of ∼1019 cm-3. Electron paramagnetic resonance (EPR) studies suggest that the Cr atoms exhibit collective magnetic behavior even at these levels. X-ray diffraction (XRD) and reflection high-energy electron diffraction (RHEED) indicate high structural quality is maintained for Cr incorporation for levels up to ∼ 1019 atoms cm-3.