METHOD FOR MANUFACTURING ELECTRONIC DEVICE

The present invention provides a method for manufacturing an electronic device including a base material that has an exposed metal portion on a surface of the base material and an electronic component that is provided on the base material. The method includes a flux treatment step of treating the exposed metal portion with a flux by bringing the exposed metal portion into contact with the flux and an introduction step of introducing a resin composition such that the resin composition comes into contact with a surface of the exposed metal portion treated with the flux. The flux contains a rosin, an activator, and a solvent. The content of the rosin is equal to or greater than 1 part by mass and equal to or smaller than 18 parts by mass with respect to 100 parts by mass of the flux. The percent change in mass of the flux before and after a heating treatment is equal to or lower than 21% by mass. The resin composition contains an epoxy resin and a phenolic resin curing agent. In a case where SP1 represents a Hansen's method-based average solubility parameter of a resin group consisting of the epoxy resin and the phenolic resin curing agent in the resin composition, and Mn1 represents a number average molecular weight of the resin group, SP1 and Mn1 satisfy Mn1≤210×SP1−4,095.