Details

Autor(en) / Beteiligte

• Biggemann, Daniel
• Tessler, Leandro R

Titel

Near infra-red photoluminescence of Nd 3+ in hydrogenated amorphous silicon sub-nitrides a-SiN x:H〈Nd

Ist Teil von

• Materials science & engineering. B, Solid-state materials for advanced technology, 2003, Vol.105 (1), p.188-191

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2003

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Neodymium-doped hydrogenated amorphous silicon sub-nitrides a-SiN x :H〈Nd〉 thin films were deposited by rf-sputtering using a Si target partially covered by metallic Nd chips and Ar+N 2+H 2 sputtering gas. Characteristic Nd 3+ near infra-red (NIR) photoluminescence (PL) was detected between 10 and 300 K with peaks at ∼935, ∼1090 and ∼1390 nm, corresponding to the intra-4f transitions 4 F 3/2→ 4 I 9/2 , 4 F 3/2→ 4 I 11/2 and 4 F 3/2→ 4 I 13/2 , respectively. Measurements using different excitation wavelengths indicate that the Nd 3+ excitation occurs through the a-SiN x :H matrix. Varying the nitrogen content x from 0 to nearly 1.3 increases the matrix bandgap. The PL efficiency is maximum when the bandgap corresponds to twice the 4 F 3/2→ 4 I 9/2 transition, indicating a defect-related energy transfer mechanism. The temperature quenching can be as low as less than a factor 3 between 10 and 300 K for 2.8 eV gap samples. Thermal annealing can enhance the PL intensity by a factor 10. Neodymium concentrations above ∼3×10 20 atoms/cm 3 slightly reduce the PL intensity probably due to excess of inactive defect centers. Along with erbium-doped amorphous silicon alloys, a-SiN x :H〈Nd〉 can be used in the development of photonic devices in the future.