Optical properties of undoped, Be-doped, and Si-doped wurtzite-rich GaAs nanowires grown on Si substrates by molecular beam epitaxy

✍ Scribed by Soo-Ghang Ihn; Mee-Yi Ryu; Jong-In Song

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 881 KB
• Volume: 150
• Category: Article
• ISSN: 0038-1098
• DOI: 10.1016/j.ssc.2010.01.037

✦ Synopsis

The photoluminescence (PL) of undoped, Si-doped, and Be-doped GaAs nanowires (NWs) grown on Si substrates by molecular beam epitaxy was investigated. PL peaks of the undoped and Be-doped NWs were observed at higher energies than the bandgap energy of GaAs bulk. According to X-ray diffraction analysis, the blue-shift is attributed to the wurtzite-rich GaAs NW structure. Impurity-related peaks were observed in the undoped NWs and the impurity was Si that diffused via interaction with the adatoms on the Si surface during the growth. A slight bandgap narrowing of the Be-doped GaAs NWs was observed from their PL spectra. The Si-doped NWs showed a very broad PL peak due to a larger density of Sirelated defects originating from the heavy doping level. The dependence of the PL peaks of the NWs on temperature was also investigated.