Overcoming degradation mechanisms in CdTe solar cells: First annual report, August 1998--August 1999

Technical Report · Mon Feb 28 04:00:00 EST 2000

DOI:https://doi.org/10.2172/754634· OSTI ID:754634

Cahen, D; Gartsman, K; Hodes, G; Rotlevy, O; Visoly-Fisher, I; Dobson, K

The authors have studied the importance of chemical processes for the stability of CdTe solar cells, in particular, diffusion in the ohmic contact/absorber junction regions. Both whole cells and test systems containing only the ohmic contact and the absorber are used. They found several experimental methods to be useable tools to follow the effects of impurity diffusion on the CdTe grain boundaries, grain bulk, and surface. In addition, they have explored alternative contacting schemes. The first year of activities led to the following tentative conclusions: Grain boundaries in CdTe/CdS cells are NOT fully passivated and are expected to be electrically active; There appears to be fast ionic diffusion in the vicinity of the Cu/HgTe/graphite back-contact, possibly enhanced by grain boundary diffusion; The macroscopic response to stress is different for cells with identical back-contact, but from different manufacturers. Different factors and/or different reactions to identical factors are possibly at work here; and Ni-P appears to be a promising back-contact material.

• Research Organization: National Renewable Energy Lab., Golden, CO (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: AC36-99GO10337
• OSTI ID: 754634
• Report Number(s): NREL/SR-520-27932
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
BACK CONTACT SOLAR CELLS
CADMIUM SULFIDES
CADMIUM TELLURIDE SOLAR CELLS
CDTE SOLAR CELLS
CONTACTS
COPPER
DEGRADATION MECHANISMS
DIFFUSION PROCESSES
ELECTRON-BEAM-INDUCED CURRENT
GRAIN BOUNDARIES
GRAPHITE
LIGHT-BEAM-INDUCED CURRENT
MERCURY TELLURIDES
NICKEL PHOSPHIDES
PERFORMANCE
PHOTOVOLTAICS
SOLAR ABSORBERS
STABILITY