(Ga,In)(N,As) lattice matched to GaAs with a band gap of 1 eV is employed as active material in high-efficiency III-V solar cells. Te-doped Ga0.934In0.066N0.023As0.977 layers were grown by metal-organic vapor-phase epitaxy on (100) GaAs. The samples were highly doped n-type with carrier concentrations ranging from about 10(17)-10(19) cm(-3). Pieces of the samples were hydrogenated with H-doses of 10(18) ion/cm(2). The optical and electrical properties of the samples before and after hydrogenation were studied by low-temperature photoluminescence and magnetotransport. In undoped samples hydrogen is known to form N-H complexes which strongly reduce the local perturbation of the lattice due to nitrogen and thus reverse the N-induced global changes of the band structure. Combined analysis of photoluminescence and transport measurements on Te-doped samples, however, indicates a competition between N H formation and passivation of the Te donor favoring the latter. Hardly any band structure changes due to hydrogenation are observed in these Te-doped samples, instead a strong reduction of the free-carrier concentration is observed after hydrogenation. (c) 2006 Elsevier B.V. All rights reserved.
Competition of N-passivation and Te-passivation in hydrogenation of Te-doped (Ga,In)(N,As) / J., Teubert; P. J., Klar; W., Heimbrodt; K., Volz; W., Stolz; Polimeni, Antonio; Capizzi, Mario. - In: PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES. - ISSN 1386-9477. - 32:1-2(2006), pp. 218-221. (Intervento presentato al convegno 12th International Conference on Modulated Semiconductor Structures (MSS12) tenutosi a Albuquerque, NM nel JUL 10-15, 2005) [10.1016/j.physe.2005.12.040].
Competition of N-passivation and Te-passivation in hydrogenation of Te-doped (Ga,In)(N,As)
POLIMENI, Antonio;CAPIZZI, Mario
2006
Abstract
(Ga,In)(N,As) lattice matched to GaAs with a band gap of 1 eV is employed as active material in high-efficiency III-V solar cells. Te-doped Ga0.934In0.066N0.023As0.977 layers were grown by metal-organic vapor-phase epitaxy on (100) GaAs. The samples were highly doped n-type with carrier concentrations ranging from about 10(17)-10(19) cm(-3). Pieces of the samples were hydrogenated with H-doses of 10(18) ion/cm(2). The optical and electrical properties of the samples before and after hydrogenation were studied by low-temperature photoluminescence and magnetotransport. In undoped samples hydrogen is known to form N-H complexes which strongly reduce the local perturbation of the lattice due to nitrogen and thus reverse the N-induced global changes of the band structure. Combined analysis of photoluminescence and transport measurements on Te-doped samples, however, indicates a competition between N H formation and passivation of the Te donor favoring the latter. Hardly any band structure changes due to hydrogenation are observed in these Te-doped samples, instead a strong reduction of the free-carrier concentration is observed after hydrogenation. (c) 2006 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
