Alpha radiation sources in low alpha materials and implications for low alpha materials refinement

摘要: Abstract Traditionally wafer bumps are made from Pb containing solders. Over 20 years ago IBM recognized that 210 has a decay chain resulting in 5.4 MeV alpha particle induces soft errors. A variety of efforts to produce and characterize low ensued. Work at Honeywell over the past several shown lead activity does not follow signature predicted secular equilibrium. Data presented indicating smelting minimal effect on Pb/ Po equilibrium other trace radionuclides source. The implications these data possible emitter sources free solders discussed, along with method developed by remove emitters solder components.