Elger, G.G.ElgerHutter, M.M.HutterOppermann, H.H.H.H.OppermannAschenbrenner, R.R.AschenbrennerReichl, H.H.ReichlJäger, E.E.Jäger2022-03-032022-03-032002https://publica.fraunhofer.de/handle/publica/20258210.1007/s005420100103A packaging process for flip-chip LEDs (light emitting diodes) is described. The LEDs are picked and placed on a silicon substrate wafer. After reflow the substrates are individualized. AuSn solder is used for the interconnection. The solder compounds, Au and Sn, are electroplated separately: Sn on the silicon substrate and Au on the chip. The interconnections formed by tin-rich and by gold-rich intermetallic phases are compared. The metallurgy and the reliability of the LEDs are investigated. The superiority of the gold-rich interconnection is demonstrated.en621journal article