Complex sentence: Monocrystalline silicon is used in the manufacturing of high performance solar cells, however since solar cells are less demanding than microelectronics regarding structural imperfections, monocrystaline solar grade (Sog-Si) is often used.
Split into simpler sentences: Monocrystalline silicon is used in the manufacturing of high performance solar cells. Since, however, solar cells are less demanding than microelectronics for as concerns structural imperfections, monocrystaline solar grade (Sog-Si) is often used.