Method for manufacturing a device comprising brazed joints made from metal oxalate

摘要

The process for fabricating a device comprising a support (S) and a component connected to each other by a solder (b1, b2), comprises performing a soldering operation using a metal oxalate. The metal oxalate is obtained by chemical precipitation of soluble metal salt with oxalic acid or ammonium oxalate dissolved in hydro-alcoholic solvents having dielectric constants of 17-80. The component and the support comprise, on their surface, a film comprising gold or copper on which the solder is formed. The solder is made of a suspension and paste containing metal oxalate. The process for fabricating a device comprising a support (S) and a component connected to each other by a solder (b1, b2), comprises performing a soldering operation using a metal oxalate. The metal oxalate is obtained by chemical precipitation of soluble metal salt with oxalic acid or ammonium oxalate dissolved in hydro-alcoholic solvents having dielectric constants of 17-80. The component and the support comprise, on their surface, a film comprising gold or copper on which the solder is formed. The solder is made of a suspension and paste containing metal oxalate. The soldering operation comprises elaborating the suspension or paste containing metal oxalate, depositing the suspension or paste to the surface of the support and/or component, assembling the support and the component via the suspension or paste, and heating the assembled support and the component. The step of elaborating the suspension or the paste comprises chemically precipitating metal soluble salt in an aqueous or hydro-alcoholic medium by oxalic acid or soluble oxalate, obtaining a precipitate of oxalate having controlled morphological and granulometric characteristics leading to particle sizes of greater than 40 nm for oxalate comprising copper and to 0.1 micron for the silver oxalate, washing the formed precipitate, and suspending the oxalate in the aqueous or hydro-alcoholic medium at a concentration to obtain suspension or paste with controlled viscosity. The step of depositing the suspension is performed by sputtering and inkjet methods. The step of depositing the paste is performed by coating and screen printing method. The process further comprises drying the suspension and paste at temperature of 100[deg] C under air or vacuum conditions. The step of heating the assembled support and component is performed at a heating rate of greater than 150[deg] C/hour.