Electron spin resonance study of hydrogenated microcrystalline silicon–germanium alloy thin films

Thin film solar cells incorporating microcrystalline Si1–xGex as efficient infrared absorber: an application to double junction tandem solar cells

“…On the other hand, open-circuit voltage (V oc ) and fill factor (FF) decrease with Ge content due to the band gap narrowing and the increased carrier recombination. As reported earlier, Ge incorporation larger than x$0.2 leads to the appreciable creation of Ge dangling bond defects (acceptorlike states) [17][18][19] by which solar cell performance is degraded severely. In contrast, the solar cell with smaller Ge content (x ¼ 0.1) maintains relatively high V oc and FF while exhibiting markedly high J sc , resulting in a higher conversion efficiency than for mc-Si:H solar cell.…”

Raman scattering and electrical characterizations studies of hydrogenated amorphous silicon–germanium alloys prepared by 40MHz plasma-enhanced CVD

“…Ge, with high density of defects [1]. These defects (Ge dangling bonds) will act as a predominant recombination center [6,14].…”

“…Recently, Chang et al also demonstrated that the spin density of undoped hydrogenated microcrystalline silicon-germanium (μc-SiGe:H) increases with Ge content, which reasonably accounts for the decreased photoconductivity [6]. Therefore, the preparation of high quality a-SiGe:H thin film becomes an important research issue.…”

Effects of process parameters onμc - Si1 − XGeX:H solar cells performance and material properties

“…The optimal germanium content in μc-SiGe:H i-layers was found to be 10% because incorporating more germanium leads to the formation of acceptor like states induced by germanium dangling bond defects that decrease the solar cell performance [10].…”