METHOD FOR MANUFACTURING LEADFRAME AND LEADFRAME

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a leadframe and the lead frame without leads for a high reliable BGA and a LGA suitable for a high density mounting wherein a leadframe manufacturing method using a conventional photo etching manner can be applied and a production efficiency can not be decreased. SOLUTION: A resist pattern 21a and a resist pattern 21b are formed on a metal base 11. The metal base 11 is etched on both sides using the resist pattern 21a and the resist pattern 21b as masks, then a penetration portion 31 and a half etch portion 32 (thin wall portion) are formed. The metal blackening treatment of the metal base 11 is performed and an oxide film 41 is formed on the metal base side surface of the penetration portion 31 and the half etch portion 32 (thin wall portion). The leadframe is obtained after removing the resist pattern 21a and the resist pattern 21b and forming a gold plating film 71 on a predetermined position of the lead using a mask plating method.