Improvement of the photoluminescence (PL) of Phosphorus (P) doped Ge by P atomic layer doping (ALD) is investigated. Fifty P delta layers of 8 Ã1013 cm-2 separated by 4 nm Ge spacer are selectively deposited at 300 Â°C on a 700 nm thick P-doped Ge buffer layer of 1.4 Ã 1019 cm-3 on SiO2 structured Si (100) substrate. A high P concentration region of 1.6 Ã 1020 cm-3 with abrupt P delta profiles is formed by the P-ALD process. Compared to the P-doped Ge buffer layer, a reduced PL intensity is observed, which might be caused by a higher density of point defects in the P delta doped Ge layer. The peak position is shifted by â¼0.1 eV towards lower energy, indicating an increased active carrier concentration in the P-delta doped Ge layer. By introducing annealing at 400 Â°C to 500 Â°C after each Ge spacer deposition, P desorption and diffusion is observed resulting in relatively uniform P profiles of â¼2 Ã 1019 cm-3. Increased PL intensity and red shift of the PL peak are observed due to improved crystallinity and higher active P concentration.
|Titolo:||Photoluminescence of phosphorus atomic layer doped Ge grown on Si|
|Data di pubblicazione:||2017|
|Citazione:||Yamamoto, Y., Nien, L., Capellini, G., Virgilio, M., Costina, I., Schubert, M.A., et al. (2017). Photoluminescence of phosphorus atomic layer doped Ge grown on Si. SEMICONDUCTOR SCIENCE AND TECHNOLOGY, 32(10), 104005.|
|Appare nelle tipologie:||1.1 Articolo in rivista|