Title :
Progress in growth of high quality amorphous silicon materials
Author :
Futako, W. ; Fukutani, K. ; Kannbe, M. ; Kamiya, T. ; Fortmann, C.M. ; Shimizu, L.
Author_Institution :
Graduate Sch. at Nagatsuta, Tokyo Inst. of Technol., Yokohama, Japan
fDate :
29 Sep-3 Oct 1997
Abstract :
The band gap of hydrogenated amorphous silicon (a-Si:H) can be tuned from 1.5 eV to 2.1 eV by intentionally promoting structural relaxation during film growth by using chemically active species such as hydrogen atom or excited argon. No marked changes were observed in the local silicon-silicon bonds such as bond-length and bond-angle distribution for these films although the band gaps were significantly changed. The dielectric constants (ε2) and weight of the films was markedly reduced in the wide gap a-Si:H materials, implying that the medium range structure of Si-network was significantly altered. The light soaking stability was improved in all cases where relaxation was promoted. The novel technique termed “Chemical Annealing” shows significant potential for fabrication of improved thin film silicon solar cells
Keywords :
amorphous semiconductors; annealing; elemental semiconductors; energy gap; hydrogen; permittivity; plasma CVD coatings; semiconductor growth; semiconductor thin films; silicon; solar cells; 1.5 to 2.1 eV; Chemical Annealing; Si:H; a-Si:H growth; band gaps; bond-angle distribution; bond-length; chemically active species; dielectric constants; excited argon; high quality amorphous silicon materials; hydrogen atom; light soaking stability; local silicon-silicon bonds; structural relaxation; thin film Si solar cells fabrication; wide gap a-Si:H materials; Amorphous silicon; Argon; Bonding; Chemicals; Dielectric constant; Dielectric materials; Hydrogen; Photonic band gap; Semiconductor films; Stability;
Conference_Titel :
Photovoltaic Specialists Conference, 1997., Conference Record of the Twenty-Sixth IEEE
Conference_Location :
Anaheim, CA
Print_ISBN :
0-7803-3767-0
DOI :
10.1109/PVSC.1997.654156
