Hydrocarbon fluxes for ionic compound free soldering: improvement by peroxide additives

Abstract

PurposeThe paper aims to focus on lowering the soldering temperature of ionic compound free soldering using 9,10‐dihydroanthracene as a hydrocarbon flux.Design/methodology/approachThe ability of 9,10‐dihydroanthracene to reduce cupric oxide in the presence of peroxides including tert‐butyl peroxybenzoate, tert‐butyl cumyl peroxide, tert‐butyl peroxide was investigated. The applicability of 9,10‐dihydroanthracene in the presence of peroxides as ionic compound free flux reagents was experimentally examined in the soldering of pre‐oxidized copper electrodes under practical conditions.FindingsThe ability of 9,10‐dihydroanthracene for the reduction of cupric oxide powder under argon atmosphere at 300°C for 120 s was found to be improved in the presence of tert‐butyl peroxybenzoate. The highest reducing ability of 9,10‐dihydroanthracene in the presence of tert‐butyl peroxybenzoate among the peroxides was in agreement with the lowest homolytical O–O bond dissociation energies of the peroxides calculated by the theoretical calculation. 9,10‐Dihydroanthracene in the presence of tert‐butyl peroxybenzoate showed the highest soldering efficiency under practical conditions (soldering temperature: 300°C) and sufficient reliability in the environmental testing.Originality/valueThe findings demonstrate that peroxide additives improve the applicability of 9,10‐dihydroanthracene as ion free soldering even under practical conditions.