Annealing of Boron-Doped Hydrogenated Crystalline Silicon Grown at Low Temperature by PECVD

Marta Chrostowski (1, 2, 3) , J Alvarez (4, 3) , Alessia Le Donne (5) , Simona Binetti (5) , Pere Roca I Cabarrocas (2, 3)

1 TOTAL S.A.
2 LPICM - Laboratoire de physique des interfaces et des couches minces [Palaiseau]
3 IPVF - Institut Photovoltaïque d’Ile-de-France (ITE)
4 GeePs - Laboratoire Génie électrique et électronique de Paris
5 MIB-SOLAR - Milano-Bicocca Solar Energy Research Center

We investigate low-temperature (<200 • C) plasma-enhanced chemical vapor deposition (PECVD) for the formation of p-n junctions. Compared to the standard diffusion or implantation processes, silicon growth at low temperature by PECVD ensures a lower thermal budget and a better control of the doping profile. We previously demonstrated the successful growth of boron-doped epitaxial silicon layers (p+ epi-Si) at 180 • C. In this paper, we study the activation of boron during annealing via dark conductivity measurements of p+ epi-Si layers grown on silicon-on-insulator (SOI) substrates. Secondary Ion Mass Spectroscopy (SIMS) profiles of the samples, carried out to analyze the elemental composition of the p+ epi-Si layers, showed a high concentration of impurities. Finally, we have characterized the p+ epi-Si layers by low-temperature photoluminescence (PL). Results revealed the presence of a broad defect band around 0.9 eV. In addition, we observed an evolution of the PL spectrum of the sample annealed at 200 • C, suggesting that additional defects might appear upon annealing.

Mots clés: silicon epitaxy; PECVD; B-H complexes

Domaines: Matière Condensée [cond-mat]; Matériaux

Marta Chrostowski, J Alvarez, Alessia Le Donne, Simona Binetti, Pere Roca I Cabarrocas. Annealing of Boron-Doped Hydrogenated Crystalline Silicon Grown at Low Temperature by PECVD. Materials, 2019, 12 (22), pp.3795. ⟨10.3390/ma12223795⟩. ⟨hal-02392513⟩