Patent ID: 6899534

Claim:
A mold assembly for encapsulating a semiconductor die and a portion of a leadframe in a transfer molding operation for forming a molded package having external surfaces formed of material used in said encapsulating of said semiconductor die and said portion of said leadframe, said assembly comprising: a top mold plate having a top and a plurality of sides; and a generally planar bottom mold plate having portions thereof for sealably engaging portions of said top mold plate during said transfer molding operation, said top mold plate and said bottom mold plate forming a mold cavity having a top, having a bottom, having sidewalls and having end walls when sealably engaged, said top mold plate and said bottom mold plate for suspending said semiconductor die and a portion of said leadframe within said mold cavity for injecting a material to encapsulate said semiconductor die and portions of said leadframe therein, one sidewall of said sidewalls having an inner surface castellated with alternating grooves and columns for forming columns and grooves in at least one external surface of said molded package, said grooves in said inner surface of said one sidewall of said sidewalls have openings therein larger than a lead of said leadframe.