MOD silver metallization for photovoltaics. Final technical report, December 1, 1983-May 31, 1985

Technical Report · Mon Jul 01 04:00:00 EDT 1985

DOI:https://doi.org/10.2172/5394895· OSTI ID:5394895

Vest, G. M.; Vest, R. W.

This was a study to investigate the feasibility of utilizing metallo-organic decomposition (MOD) silver inks for front contact metallization of solar cells. Generic synthesis procedures were developed for all metallo-organic compounds investigated. Silver neodecanoate was found to be the most suitable silver metallo-organic compound for use in thick film inks. Benzene was the most suitable solvent investigated for silver neodecanoate, and tetrahydrofuran was a less desirable alternative. A combination of neodecanoic acid and butyl carbitol acetate imparted suitable rheology to silver MOD inks for screen printing. A permanent binding agent was found to be necessary to obtain reproducible, long term adhesion. Bismuth 2-ethylhexanoate, which decomposes to bismuth oxide upon firing, was shown to be suitable for this purpose. Both platinum 2-ethylhexanoate and bismuth 2-ethylhexanoate, which respectively decompose to platinum and bismuth oxide, were suitable for imparting solder leach resistance to the silver films. Ink SC-10Y, which produces fired films of theoretical metallic composition 99 w/o Ag-1 w/o Bi, was the most suitable of all inks developed for solar cell front contact metallization. The contacts fabricated with it exhibited long term adhesion, excellent solderability and solder leach resistance, and a dense microstructure. The preferred firing sequence for ink SC-10Y involves a 70 minute cycle with a maximum temperature of 292/sup 0/C. The combination of HF cleaning and the preferred firing sequence produced a high resistance back contact with certain lots of solar cells. This observation requires that changes be made either in the metallurgy of the back contact or in the processing of the MOD inks.

• Research Organization: Purdue Univ., Lafayette, IN (USA)
• DOE Contract Number: NAS-7-100-956679
• OSTI ID: 5394895
• Report Number(s): DOE/JPL/956679-84; ON: DE85015758
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
ADHESION
CHEMICAL REACTIONS
DECOMPOSITION
DIRECT ENERGY CONVERTERS
ELECTRIC CONDUCTIVITY
ELECTRIC CONTACTS
ELECTRICAL EQUIPMENT
ELECTRICAL PROPERTIES
ELEMENTS
EQUIPMENT
FABRICATION
FILMS
METALS
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
SILVER
SOLAR CELLS
SOLAR EQUIPMENT
SUBSTRATES
TEMPERATURE DEPENDENCE
THIN FILMS
TRANSITION ELEMENTS