Schmid Group products

In recent years SCHMID has developed several equipment for the production of bifacial solar cells. This cell type absorbs light and generates electricity on both surfaces and achieves up to 30 % higher yield than conventional cells, if suitably installed in open areas or flat roofs.

A large part of the red light (long wave) penetrates conventional solar cells without power generation. Since the introduction of PERC (Passivated Emitter Rear Cell) technology this light is exploited as well: A dielectric layer on the back of the cell reflects the light which penetrates through to the rear side without generation of charge carriers. The photons thus obtain a “second chance” to generate electricity. Consequently the efficiency of the solar cell increases.

Based on n-type material PERL cells have a long life expectancy and achieve an efficiency potential of 25 %. Combined with the per se bifaciality of this cell architecture up to 40 % higher energy harvest in PV installations can be achieved. The simple manufacturing process based on the SCHMID co-diffusion leads to best of class conversion costs.

Unlike standard cells and PERC, which both use an aluminum-alloy BSF, PERT (Passivated Emitter Rear Totally Diffused) cells have a diffused rear surface. That means, with p-PERT the emitter of p-type based wafer is formed with phoshphorus diffusion and BSF is realized with boron doping. PERT cells do not show the considerably light-induced degradation and can be adapted to bifacial.