Patent ID: 8492202

Claim:
A method of manufacturing a semiconductor device comprising a semiconductor assembly and insulating molding compounds, the semiconductor assembly comprising: a metal leadframe having an external-extraction metal lead and a bonding portion; a semiconductor chip die-bonded onto the bonding portion on the metal leadframe via a joint layer and having a rear-surface electrode; and a joint member electrically connecting an electrode formed on a main surface of the semiconductor chip and the external-extraction metal lead, the insulating molding compounds being formed so as to cover the semiconductor chip and a periphery of the semiconductor chip, and the method comprising the steps of: (a) die-bonding the semiconductor chip to the bonding portion on the metal leadframe by a conductive material containing Ag; (b) electrically connecting the electrode on the main surface of the semiconductor chip and the external-extraction metal lead; (c) after the step of (b), coating an organic metal compound solution on the semiconductor assembly; (d) after the step of (c), heating the semiconductor assembly on which the organic metal compound solution is coated, thereby forming a metal oxide film on a surface of the semiconductor assembly by sintering; and (e) molding the insulating molding compounds so as to cover at least a part of the semiconductor chip, the joint member, and the metal leadframe and then performing hardening treatment thereto, wherein the die-bonding step in the step of (a) includes the steps of: supplying, on the metal leadframe, the conductive material containing Ag made of Ag fine particles having a diameter of 1 μm or smaller, an organic material evaporated and disappearing under an oxidizing atmosphere at 300° C. or lower, and conductive metal particles each having a diameter larger than 15 μm and smaller than 150 μm; mounting the semiconductor chip by pushing it from above the conductive material containing Ag; and after the mounting step, heating the semiconductor assembly under an oxidizing atmosphere at a temperature of 150 to 300° C., thereby forming the joint layer.