Patent ID: 9607933
Date: 2017-03-28
CPC Classifications: H01L,Y10T

Claim:
1. A lead frame structure for quad flat no-lead (QFN) package, comprising: a main base, having a center area for carrying a semiconductor die, and a periphery area surrounding the center area; a plurality of terminals arranged around the main base; and a first metal layer, having a first part formed on the periphery area of the main base, and a second part formed on the plurality of terminals, wherein the first part of the first metal layer is firmly fixed on a front surface of the main base and the second part of the first metal layer is firmly fixed on front surfaces of the plurality of terminals; wherein the main base and the terminals are formed by a stamping process, and the first metal layer is formed by a plating process before the stamping process, wherein before the main base and the terminals are formed, a rear surface of the metal base and the terminals are half etched to reduce a thickness of said metal base at an opposite side where the area of the first metal layer is formed, wherein the lead frame structure further comprises another metal layer for covering a rear surface of the main base and covering rear surfaces and side walls of the plurality of terminals.