Patent EP-4315404-A1 (EP)
Title: Method for mounting an electronic component onto a substrate by pressing, using a sintering material
Inventor: RIOU JEAN-CHRISTOPHE
IPC: H01L21/603
Filed: 2022-03-28
Abstract: A method for mounting an electronic component (28) onto a substrate (30) comprises the following consecutive steps: - forming a stack comprising a substrate (30), an electronic component (28) and a sintering material (26) between the electronic component (28) and the substrate (30); - hot-pressing the stack so as to cause the temperature of the sintering material (26) to exceed a preliminary exothermal peak (8) that precedes an exothermal sintering peak (10), without the temperature of the sintering material (26) reaching a maximum of the exothermal sintering peak (10); and –heating the stack so as to sinter the sintering material (26) (e.g. at atmospheric pressure). "Bridges" are formed between the particles of sintering material (26) and grow as soon as the preliminary exothermal peak (8) has been reached. The sintering material (26) can be cut out of a sheet before the stack is formed. The method can include a preliminary step of heating a test sample of the sintering material (26) by subjecting said sample to an increasing temperature, wherein, during the heating process, a temperature of the sintering material (26) is measured, and a first heating temperature value that corresponds to a maximum preliminary exothermal peak (8) preceding the exothermal sintering peak (10) as well as a second heating temperature value that corresponds to the maximum exothermal sintering peak (10) are detected. The stack can be a first stack, the electronic component (28) can be a first component, and the sintering material can form a first portion, the method also comprising the following steps: - forming at least a second stack comprising the substrate (30), a second electronic component (28) and a second portion of the sintering material (26) between the second electronic component (28) and the substrate (30); - hot-pressing the second stack so as to cause the temperature of the material to exceed the preliminary exothermal peak (8), without the temperature of the sintering material (26) reaching the value that equals the maximum preliminary exothermal peak (8) at the exothermal sintering peak (10); and - carrying out the heating step so as to simultaneously heat all of the stacks. The first and second electronic components (28) can have different thicknesses. The stack can also be a first stack, the electronic component (28) can be a first component, the sintering material (26) can form a first portion, and the substrate can be a first substrate, the method also comprising the following steps: - forming a second stack comprising a second substrate (30), a second electronic component (28) and a second portion of the sintering material (26) between the second electronic component (28) and the second substrate (30); - independently of the step of pressing the first stack, hot-pressing the second stack so as to cause the temperature of the material to exceed the preliminary exothermal peak (8), without the temperature of the sintering material (26) reaching the value that equals the maximum preliminary exothermal peak (8) at the exothermal sintering peak (10); mounting the first substrate (30) onto the second substrate (30) by inserting the first electronic component (28) and the second electronic component (28) between the first substrate (30) and the second substrate (30); and - carrying out the heating step so as to simultaneously heat all of the stacks.