Method for manufacturing multilayer printed wiring board

A method for manufacturing a multilayer printed wiring board, the method comprising:

• forming a first stack by stacking a first sheet of metal foil, a first prepreg, and a second sheet of metal foil, one on top of another such that the first prepreg is interposed between the first sheet of metal foil and the second sheet of metal foil;
• forming a first insulating layer from the first prepreg by thermally pressing the first stack and thereby thermally curing the first prepreg to make a double-sided metal-clad laminate in which the second sheet of metal foil, the first insulating layer, and the first sheet of metal foil are stacked one on top of another in this order;
• forming conductor wiring by partially removing the first sheet of metal foil from the double-sided metal-clad laminate to make a printed wiring board in which the second sheet of metal foil, the first insulating layer, and the conductor wiring are stacked one on top of another in this order;
• forming a second stack by stacking the conductor wiring of the printed wiring board, a second prepreg, and a third sheet of metal foil, one on top of another such that the second prepreg is interposed between the conductor wiring of the printed wiring board and the third sheet of metal foil;
• and
• forming a second insulating layer from the second prepreg by thermally pressing the second stack without preheating and thereby thermally curing the second prepreg,
• in forming the second stack, the third sheet of metal foil after having been preheated being stacked on the second prepreg without preheating the printed wiring board and the second prepreg,
• the first insulating layer having a lower linear expansion coefficient than any of the first sheet of metal foil or the second sheet of metal foil does.