ACID COPPER ELECTROPLATING SOLUTION, METHOD FOR FORMING PREFORM LAYER, METHOD FOR MANUFACTURING JUNCTION SHEET, METHOD FOR MANUFACTURING JUNCTION SUBSTRATE, AND METHOD FOR MANUFACTURING JUNCTION BODY

To provide an acid copper electroplating solution capable of forming a porous preform layer in a simple process, a method for forming a preform layer using the same, and a method for manufacturing a junction sheet including the preform layer.SOLUTION: An acid copper electroplating solution includes soluble copper salt, a specific azole compound, which is a copper ion electrocrystallization inhibitor containing two or more nitrogen atoms, acid, and water. A copper concentration is higher than or equal to 0.1 mol/L, an azole compound concentration is higher than or equal to 10 mmol/L and less than or equal to 50 mmol/L, and a chloride ion concentration is less than or equal to 10 ppm. A porous preform layer in which an average porosity consisting of copper particles is 11% to 17% is formed on one or both surfaces of a copper sheet and a substrate as a copper plating film by arranging a copper sheet or a substrate on the cathode side in the acid copper electroplating solution and performing copper electroplating. A surface of a copper particle is covered with smaller copper nanoparticles than an average particle size of the copper article.SELECTED DRAWING: Figure 1 【課題】簡単なプロセスで多孔質のプリフォーム層を形成し得る酸性電解銅めっき液及びこれを用いたプリフォーム層の形成方法並びにこのプリフォーム層を有する接合用シートの製造方法を提供する。【解決手段】酸性電解銅めっき液は、可溶性銅塩と、窒素原子を２つ以上含む銅イオン電析抑制剤である特定のアゾール化合物と、酸と、水とを含み、銅濃度が０．１ｍｏｌ／Ｌ以上であり、アゾール化合物濃度が１０ｍｍｏｌ／Ｌ以上５０ｍｍｏｌ／Ｌ以下であり、塩化物イオン濃度が１０ｐｐｍ以下である。この酸性電解銅めっき液内のカソード側に銅シート又は基板を配置して、電解銅めっきを行うことにより、銅シート又は基板の片面又は両面に、銅めっき皮膜として、銅粒子からなる平均空孔度が１１％～１７％である多孔質のプリフォーム層を形成する。銅粒子の表面が、銅粒子の平均粒径より小さい銅ナノ粒子で被覆されている。【選択図】図１