Lead frame strips with electrical isolation of die paddles

摘要

A lead frame strip includes connected unit lead frames each having a die paddle, a tie bar directly connecting the die paddle to a periphery of the unit lead frame, leads directly connected to the periphery of the unit lead frame and projecting toward the die paddle, and an opening in the periphery adjacent the tie bar. The openings in the periphery of the unit lead frames are spanned with an electrically insulating material that connects the tie bar of each unit lead frame to the periphery of the unit lead frame. The direct connections between the tie bars and the periphery of the unit lead frames are severed prior to subsequent processing, so that the tie bars remain connected to the periphery of the unit lead frames by the electrically insulating material and the die paddles are electrically disconnected from the periphery of the unit lead frames.

主权项

1. A method of processing a lead frame strip including a plurality of connected unit lead frames, each unit lead frame having a die paddle, a tie bar directly connecting the die paddle to a periphery of the unit lead frame, a plurality of leads directly connected to the periphery of the unit lead frame and projecting toward the die paddle, and an opening in the periphery adjacent the tie bar, the method comprising:
attaching a semiconductor die to each of the die paddles; spanning the openings in the periphery of the unit lead frames with an electrically insulating material that connects the tie bar of each unit lead frame to the periphery of the unit lead frame; covering the unit lead frames with a molding compound so that part of each tie bar and lead remains uncovered by the molding compound; severing the direct connection between the leads and the periphery of the unit lead frames and the direct connection between the tie bars and the periphery of the unit lead frames, so that the tie bars remain connected to the periphery of the unit lead frames by the electrically insulating material and the die paddles are electrically disconnected from the periphery of the unit lead frames; and processing the lead frame strip after the severing of the direct connections.