▁with ▁some ▁continuous ▁or ▁mass ▁production ▁system ▁like ▁roll - to - roll ▁production ▁mechanism . ▁ ▁R ear ▁surface ▁pass iv ation ▁▁ ▁Con cept s ▁of ▁the ▁rear ▁surface ▁pass iv ation ▁for ▁C IG S ▁solar ▁cells ▁shows ▁the ▁potential ▁to ▁improve ▁the ▁efficiency . ▁The ▁rear ▁pass iv ation ▁concept ▁has ▁been ▁taken ▁from ▁pass iv ation ▁technology ▁of ▁Sil icon ▁solar ▁cells . ▁Al 2 O 3 ▁and ▁Si O 2 ▁have ▁been ▁used ▁as ▁the ▁pass iv ation ▁materials . ▁N ano - s ized ▁point ▁contacts ▁on ▁Al 2 O 3 ▁layer ▁ ▁and ▁line ▁contacts ▁on ▁Si O 2 ▁layer ▁ ▁provide ▁the ▁elect rical ▁connection ▁of ▁C IG S ▁absor ber ▁to ▁the ▁rear ▁electro de ▁Mol y b den um . ▁The ▁point ▁contacts ▁on ▁the ▁Al 2 O 3 ▁layer ▁are ▁created ▁by ▁e - be am ▁l ith ography ▁and ▁the ▁line ▁contacts ▁on ▁the ▁Si O 2 ▁layer ▁are ▁created ▁using ▁phot ol ith ography . ▁It ▁is ▁also ▁seen ▁that ▁the ▁implementation ▁of ▁the ▁pass iv ation ▁layers ▁does ▁not ▁change ▁the ▁morph ology ▁of ▁the ▁C IG S ▁layers ▁ ▁See ▁also ▁▁▁ ▁List ▁of ▁C IG S ▁companies ▁ ▁C Z TS ▁ ▁References ▁ ▁External ▁links ▁▁ ▁Co pper ▁Ind ium ▁Dis elen ide ▁Publications , ▁Pres ent ations , ▁and ▁News ▁Database ▁of ▁the ▁National ▁Ren ew able ▁Energy ▁Labor atory . ▁World ' s ▁L arg est ▁C IG S ▁Sol ar ▁Array ▁Oper