skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Atomic-scale characterization of hydrogenated amorphous-silicon films and devices. Annual subcontract report, 14 February 1994--14 April 1995

Technical Report ·
DOI:https://doi.org/10.2172/95549· OSTI ID:95549
; ; ;  [1]
  1. National Inst. of Standards and Technology, Boulder, CO (United States)

Properties of the hydrogenated amorphous silicon (a-Si:H) films used in photovoltaic (PV) panels are reported. The atomic-scale topology of the surface of intrinsic a-Si:H films, measured by scanning tunneling microscopy (STM) as a function of film thickness, are reported and diagnosed. For 1-500-nm-thick films deposited under normal device-quality conditions from silane discharges, most portions of these surfaces are uniformly hilly without indications of void regions. However, the STM images indicate that 2-6-nm silicon particulates are continuously deposited into the growing film from the discharge and fill approximately 0.01% of the film volume. Although the STM data are not sensitive to the local electronic properties near these particulates, it is very likely that the void regions grow around them and have a deleterious effect on a-Si:H photovoltaics. Preliminary observations of particulates in the discharge, based on light scattering, confirm that particulates are present in the discharge and that many collect and agglomerate immediately downstream of the electrodes. Progress toward STM measurements of the electronic properties of cross-sectioned a-Si:H PV cells is also reported.

Research Organization:
National Renewable Energy Lab. (NREL), Golden, CO (United States); National Inst. of Standards and Technology, Boulder, CO (United States)
Sponsoring Organization:
USDOE, Washington, DC (United States)
DOE Contract Number:
AC36-83CH10093
OSTI ID:
95549
Report Number(s):
NREL/TP-411-8246; ON: DE95009287
Resource Relation:
Other Information: PBD: Aug 1995
Country of Publication:
United States
Language:
English