Abstract: There is provided a method, mold and apparatus for encapsulating and underfilling an integrated circuit chip assembly including an integrated circuit chip mounted on a substrate in a standoff relationship. The mold has a first portion and a second portion with the first portion having first and second cavities and at least one channel interconnecting said first and second cavities. The first cavity is adapted to enclose said integrated circuit chip on said substrate. Means, e.g., a clamp, applies a clamping force to the first and the second portions of the mold to clamp the substrate between the first and second portions with the integrated circuit chip located in the first cavity. Vent means exhausts air from the first cavity.