Title :
Boron diffused emitters passivated with Al2O3 films
Author :
Masmitja, G. ; Ortega, P. ; Lopez, German ; Calle, E. ; Garcia, M.A. ; Martin, I. ; Orpella, A. ; Voz, C. ; Alcubilla, R.
Author_Institution :
Micro & Nano Technol. Res. group MNT, Univ. Politec. de Catalunya UPC, Barcelona, Spain
Abstract :
In this work we study the fabrication and characterization of boron diffused emitters using FZ c-Si(n) substrates. Emitter surface was passivated with Al2O3(25 nm thick) layers deposited by thermal atomic layer deposition ALD technique. This study covers a broad emitter sheet resistance Rsh range from 20 to 250 Ω/sq using both polished and textured wafers. Emitter electrical quality was tested by means of lifetime measurements using quasi-stationary photoconductance QSS-PC method. Dark saturation emitter current densities Joe´s were extracted from lifetime measurements resulting in Joe´s values ranging from 10 to 150 fA/cm2 depending on Rsh. These results are in the-state-of-the-art in boron emitter passivation.
Keywords :
aluminium compounds; atomic layer deposition; boron; current density; diffusion; elemental semiconductors; passivation; silicon; solar cells; Al2O3; B; FZ substrates; Si; boron diffused emitters; dark saturation; emitter current densities; emitter electrical quality; emitter sheet resistance; emitter surface; lifetime measurements; passivation; polished wafer; quasistationary photoconductance method; size 25 nm; textured wafer; thermal atomic layer deposition; Aluminum oxide; Boron; Passivation; Photovoltaic cells; Silicon; Surface resistance; A1203; Boron emitter; lifetime; silicon; solar cells;
Conference_Titel :
Electron Devices (CDE), 2013 Spanish Conference on
Conference_Location :
Valladolid
Print_ISBN :
978-1-4673-4666-5
Electronic_ISBN :
978-1-4673-4667-2
DOI :
10.1109/CDE.2013.6481409