A semiconductor package may include a first substrate, a second substrate facing the first substrate, a plurality of first electrical connections disposed between the first substrate and the second substrate, and a first material disposed between the first substrate and the second substrate. The plurality of first electrical connections may electrically couple the first substrate and the second substrate to each other. The first material may surround each of the plurality of first electrical connections, and a width of the first material proximal the first substrate may be smaller than a width of the first material proximal the second substrate.