Molecular beam epitaxy of band gap tunable ternary semiconducting silicides Ba1−xSrxSi2 for photovoltaic application

Photoresponse properties of BaSi2 epitaxial films grown on the tunnel junction for high-efficiency thin-film solar cells

“…This might be the reason why the experimental study has revealed that BaSi 2 has a very large absorption coefficient of over 10 5 cm -1 at 1.5 eV in spite of its indirect band gap nature [9]. In addition, it was found from the optical absorption measurements that the band gap of BaSi 2 can be increased up to approximately 1.4 eV [10,11], matching the solar spectrum, by replacing half of the Ba atoms with isoelectric Sr atoms. This band gap tenability was theoretically supported [8].…”

Assessment of the possibility of band gap widening of BaSi2 by incorporation of carbon

“…BaSi 2 has been attracting a recent attention for a good candidate material of solar cell [1] but its observed band gap (E g ) value is about 1.1e1.3 eV, which is narrower than the suitable gap value (w1.4 eV [2]). Therefore, development of techniques to widen E g value is earnestly expected.…”

“…If band gap widening is possible by doping of an element in the same group of the Periodic [1] and succeeded in widening of E g of BaSi 2 . 1 As for the effect of replacement of Si by elements belonging to the same group, BaGe 2 , which has the same crystal structure with BaSi 2 , has been known to have a narrower gap than BaSi 2 .…”

Investigation of the tunneling properties and surface morphologies of BaSi2/Si tunnel junctions for BaSi2 solar cell applications

“…Ba is the 16 th abundant element in Earth's crust, and the content is much higher than that of In and Se. The band gap of BaSi 2 is approximately 1.3 eV [5][6][7], which matches the solar spectrum much better than crystalline Si [8]. Both theoretical and experimental researches have revealed that BaSi 2 has a very large absorption coefficient of approximately 3×10 4 cm -1 at 1.5 eV [7].…”