A package stack may include a first package and a second package. The
first package may have an IC chip with an active surface and a back
surface. The active surface may be connected to a first major surface of
a first circuit substrate. The second package may include a second IC
chip with an active surface and a back surface. The back surface of the
second IC chip may be attached to a first major surface of a second
circuit substrate and the active surface of the second IC chip may be
electrically connected to the first major surface of the second circuit
substrate. The first package may be stacked on the second package so that
the active surface of the second package may be electrically connected to
a second major surface of the first circuit substrate of the first
package. A method may involve providing a first package having a first IC
chip and a first circuit substrate and providing a second package having
a second IC chip and a second circuit substrate. The first and the second
packages may be stacked so that the active surface of the second IC may
face and be electrically connected to a major surface of the first
circuit substrate.