Linde in Solar. - Linde Gas

08 Linde in SolarThe industry continues to build capacityand make advances in crystalline silicon.Crystalline silicon solar cells are currently used in more than 80% of worldwide solar installations.Applications are primarily consumer based (on-grid) installations, but also provide a flexible means ofsupporting underdeveloped (off-grid) locations where grid power is unavailable. Crystalline silicon celloutput is expected to continue to grow at 20-30% year on year for the next several years.Silicon cost represents 60% of the overall c-Si cell manufacturing costs, although this is expected to declineas new global Si capacity comes on stream. The process materials component cost (7%) plays a critical rolein enabling higher cell efficiencies and lower production costs.Wafer Fabrication PlantHF/Nitric etch mixes pc-SiNaOH or KOH mc-Si + IPAHF/Nitric etch mixes pc-SiNaOH or KOH mc-Si & IPARaw MaterialProcessingPoly & MonoSi GrowthEtch & WashSawWash &SeparateWaferCrystalline Cell Critical Manufacturing StepsHF/Nitric etch mixes multi c-SiKOH+IPA or NaOH+IPA mono c-SiH 2 0 2 + HCl metallic removalPOCl 3 diffusionH 3 PO 4 mist + thermalEthanol + H 3 PO 4 mixO 3 /dilute HF (RENA)HF + hot airCF 4 /0 2 plasma etchHF or dilute HF etchHF +HNO 3 (multi c-Si)or YAG Laser at end of lineWafersWire Saw Damage& Texture EtchIon Doping& DiffusionPSGRemovalEdgeIsolationRemovalPre-ARCDepositionCleanPassivation& ARCLayer (SiN)BackReflectorContactMetalsCo-FiringFurnaceModuleAssemblyHCl + H 2 0HF + H 2 OSC1 clean (H 2 O 2 + NH 4 OH)SC2 clean (H 2 0 2 +HCl)SiH 4 /NH 3 /H 2 PECVDorN 2 Si PVD SputteringWet Chemistry Application ProcessGas Application Process