SEMICONDUCTOR DEVICE MANUFACTURING METHOD AND SEMICONDUCTOR DEVICE

PROBLEM TO BE SOLVED: To mount a semiconductor chip by a versatile method that can obtain reliability under a favorable high temperature environment to allow a high temperature operation of a semiconductor device.SOLUTION: A semiconductor device manufacturing method comprises: sandwiching a bonding layer including a bonding support layer containing any metal selected form Cu, Al, Ag, Ni, Cr, Zr, Ti or an alloy of the metal, and melting layers laminated so as to sandwich the bonding support layer and containing any metal selected from Sn, Zn, In or an alloy composed of more than one metal selected from the metals between a mounting substrate and a semiconductor chip, in which the melting layer is formed on the outermost layer; and maintaining a temperature at a melting temperature and over of the melting layer to form an alloy layer having a melting point higher than that of the melting layer by liquid phase diffusion thereby to bond the mounting substrate and the semiconductor chip.