Understanding PV Module Assembly and Its Applications

Providers of EMS solutions that typically rely on SMT ( Surface Mount Technology) are constantly seeking ways to fill and diversify their capacity. One of the ways to achieve these goals is by implementing a PV (photovoltaic) module assembly where photovoltaic cell stringing can make SMT processing and materials more efficient. Fluxes, solders, and reflow technologies can generate electrical interconnects in c-Si and a-Si photovoltaic assembly technology. Moreover, the thriving demand for clean energy has made PV module production more popular. As a result, production of PV modules nearly double each year.

Currently, there are four kinds of PV modules: CIGS (copper-indium-gallium-selenium), Si (silicon), a-Si (amorphous silicon), and CdTe (cadmium-telluride). CdTe, a-Si, and CIGS are among the latest PV assembly technologies. CIGS has a promising life cycle, so it is deemed reliable, efficient, and cost-effective, especially for start-up companies. Established companies are using the technology, too.

CdTe is a known cost-effective photovoltaic technology characterized by a thin film, and it has been around for years. PV modules that are made with this technology can deliver abundant power at a low cost. a-Si, a non-crystalline silicon material, is made using CVD (chemical vapor deposition) for optical coating layering over larger areas when temperatures are low. This way, deposition on a polymer substrate can occur to create thin-film and flexible solar cells. Si and crystalline are the conventional and widely used technologies in almost 80% of the solar module assembly industry.

PV module assembly can be successful with the right SMT materials, like solder wire, fluxes, solder preforms, and solder pastes. These are the necessary materials for making interconnects during the assembly of photovoltaic solar cell modules. WEEE (Waste Electrical & Electronic Equipment) and RoHS (Restriction of Hazardous Substances) initiatives are not applicable to the solar industry, so manufactures may use solder alloys made of Sn/Pb (tin-lead) for interconnects, with the popular choices being Sn62 and Sn60. Sn/Ag (tin-silver) alloys may be used occasionally, as well as Sn/Ag/Cu or SAC (tin-silver-copper) alloys like SAC305 on some applications. A solder can be up to 0.001" or 1mm thick.

PV ribbon or tabbing ribbon is a crucial interconnect material throughout PV module assembly. It is made of solder-coated OFHC (oxygen-free high conductivity) copper ribbon, which is considered ‘dead soft’. The PV ribbon carries current from every PV cell to the bus, which is the larger tabbing ribbon that sends power from PV cell clusters to the power output or junction box of the module.

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Alpha Assembly Solutions Inc. is a premier company engaged in the development and manufacture of high quality electronics assembly materials. Since the year of its inception, way back in 1872, the company has played its role on the frontline of innovation, bringing many first-to-market products to the fore thereby, creating a premier niche for itself in the market.

Alpha Assembly Solutions Inc. is the global leader in the development, manufacturing and sales of innovative specialty materials used in a wide range of industry segments, including electronics assembly, power electronics, die attach, LED lighting.