Wafer-based silicon photovoltaic (PV) production has only changed slightly in the last forty years. The standard concept comprises p-type silicon wafers, fired contacts and encapsulation. Cost reduction is necessary if PV is to survive without feed-in tariffs and be competitive with grid electricity costs. Therefore levelised cost of electricity (LCOE) is one of the primary metrics for the cost of electricity produced by both utility scale and distributed power systems. The fastest path to lower LCOE is to introduce high efficiency solar cell concepts like the heterojunction SOLAR CELLS technology (HJT).

Meyer Burger develops solar technology – from wafers to complete PV systems – with the aim of promoting the widespread use of photovoltaics and making solar power a first-choice source of renewable energy. To this end, the company focuses strongly on developing solar cell technologies which allows highest efficiencies and highest energy output at lowest production costs.

Heterojunction cell technology combines the advantages of mono crystalline silicon (c-Si) solar cells with the good absorption and the superior passivation characteristics of amorphous silicon (a-Si) known from a-Si thin film technology using readily available materials. The HJT design is not new. Sanyo (now Panasonic) first pushed this technology into mass production achieving around
20% cell efficiency.

Heterojunction cell technology combines the advantages of mono crystalline silicon (c-Si) solar cells with the good absorption and the superior passivation characteristics of amorphous silicon (a-Si) known from a-Si thin film technology using readily available materials. The HJT design is not new. Sanyo (now Panasonic) first pushed this technology into mass production achieving around 20% cell efficiency.

The simple structure of a HJT cell is shown in below Figure . The thin intrinsic a-Si:H layers deposited between c-Si wafer and doped layers are key to achieving maximum performance from the cell structure. They result in reduced interface state density, decreased surface recombination losses and lower the emitter saturation currents.