Erfurt, D.; Koida, T.; Heinemann, M.D.; Li, C.; Bertram, T.; Nishinaga, J.; Szyszka, B.; Shibata, H.; Klenk, R.; Schlatmann, R.: Impact of rough substrates on hydrogen-doped indium oxides for the application in CIGS devices. Solar Energy Materials and Solar Cells early view (2020)
10.1016/j.solmat.2019.110300
Open Access Version
Abstract:
Indium oxide based transparent conductive oxides (TCOs) are promising contact layers in solar cells due totheir outstanding electrical and optical properties. However, when applied in Cu(In,Ga)Se2or Si-hetero-junctionsolar cells the specific roughness of the material beneath can affect the growth and the properties of the TCO.We investigated the electrical properties of hydrogen doped and hydrogen-tungsten co-doped indium oxidesgrown on rough Cu(In,Ga)Se2samples as well as on textured and planar glass. At sharp ridges and V-shapedvalleys crack-shaped voids form inside the indium oxide films, which limit the effective electron mobilityof the In2O3:H and In2O3:H,W thin films. This was found for films deposited by magnetron sputtering andreactive plasma deposition at several deposition parameters, before as well as after annealing and solid phasecrystallization. This suggests universal behavior that will have a wide impact on solar cell devices