The effect of chlorine on dopant activation in hydrogenated amorphous silicon

Citation
Am. Payne et S. Wagner, The effect of chlorine on dopant activation in hydrogenated amorphous silicon, APPL PHYS L, 76(20), 2000, pp. 2949-2951
Citations number
9
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
APPLIED PHYSICS LETTERS
ISSN journal
0003-6951 → ACNP
Volume
76
Issue
20
Year of publication
2000
Pages
2949 - 2951
Database
ISI
SICI code
0003-6951(20000515)76:20<2949:TEOCOD>2.0.ZU;2-F
Abstract
The dark conductivity of hydrogenated amorphous silicon (a-Si:H) films depo sited from dichlorosilane (SiCl2H2) and silane (SiH4), and doped with dibor ane (B2H6), increases by as much as a factor of 100 over the usual a-Si:H,B films deposited without SiCl2H2. The effect is observed at gas phase conce ntrations of diborane ranging from 0.006 to 0.5 vol %, and for both direct current (dc) and 13.56 MHz radio frequency plasma depositions, although it is more noticeable for the dc discharge. An increase in dark conductivity i s also observed in boron doped hydrogenated amorphous silicon carbon alloys (a-SiC:H) deposited with dichlorosilane, albeit coupled with a change in t he Tauc gap. Chlorine reduces the conductivity of undoped and phosphorus do ped a-Si:H films. A B-Cl cluster acceptor that is not passivated by H is pr oposed as a possible mechanism for chlorine enhanced conductivity. This inc rease in p-layer conductivity translates into an increase of solar cell eff iciency, but surprisingly by an increase in photocurrent rather than open c ircuit voltage. (C) 2000 American Institute of Physics. [S0003- 6951(00)021 20-3].