Donald C. Abbott
Texas Instruments
Attleboro, MA
d-abbott1@ti.com
Abstract:
Lead
(Pb)-free electronics present two primary challenges to IC manufacturers.
First, eliminate Pb from the IC package and second, develop IC’s that will
withstand the rigors of reflow at up to 260°C.
This talk will concentrate on the first challenge.
Nickel-palladium
(NiPd) based lead finishes have been in commercial use since 1989, with more
the 50B devices now in the field from one semiconductor house alone. The NiPd finish has recently been modified
to a nickel-palladium-gold finish. These are preplated (PPF) leadframe
finishes, that eliminates the need for plating after assembly/encapsulation.
The structure and features of both Pd based finishes will be discussed.
That
NiPd based finishes have not become more prevalent in the industry is a
conundrum. There are advantages to any
type of preplated leadframe that are obvious. There are some advantages to Pd
based finishes that are less obvious. The disadvantages and risks, real and
perceived, associated with NiPd based
finishes will also be covered.