Title :
The influence of annealing on the passivation quality of A-SiCX:H on crystalline silicon and germanium surfaces
Author :
Suwito, D. ; Fernandéz, J. ; Janz, S. ; Dimroth, F. ; Glunz, S.W.
Author_Institution :
Fraunhofer Inst. for Solar Energy Syst., Freiburg, Germany
Abstract :
This paper is addressed to the surface passivation of c-Si and c-Ge wafers by plasma enhanced chemical vapor deposition (PECVD) of Si-rich a-SiCx. We report upon excellent effective lifetimes on 1 ¿cm CZ p-Ge substrates exceeding 400 ¿s after an annealing step of 450°C. The comparison of the thermal stability of the passivation quality on the respective substrates reveals experimentally, that contrary to the system c-Si/a-SiCx, hydrogen plays a minor role in the electrical passivation of c-Ge surfaces by a-SiCx. This phenomenon is discussed considering the different work functions and band gaps of the respective materials and different possibilities for the role of carbon in the passivating matrix are outlined.
Keywords :
annealing; energy gap; hydrogen; passivation; plasma CVD; silicon compounds; substrates; thermal stability; wide band gap semiconductors; work function; SiC:H; annealing; band gaps; crystalline germanium surfaces; crystalline silicon surfaces; effective lifetimes; electrical passivation; plasma enhanced chemical vapor deposition; substrates; surface passivation; temperature 450 degC; thermal stability; work functions; Annealing; Chemical vapor deposition; Crystallization; Germanium; Hydrogen; Passivation; Plasma chemistry; Plasma stability; Silicon; Thermal stability;
Conference_Titel :
Photovoltaic Specialists Conference (PVSC), 2009 34th IEEE
Conference_Location :
Philadelphia, PA
Print_ISBN :
978-1-4244-2949-3
Electronic_ISBN :
0160-8371
DOI :
10.1109/PVSC.2009.5411186
