In an expanding device that can more effectively expand an adhesive tape in its wafer-attached region and can pick up components on the adhesive tape with high accuracy, a central first portion of an adhesive tape, including a portion with a wafer attached thereto, is laid on a top surface of a heating table, a non-heated ring is disposed to surround an outer peripheral edge of the heating table, a heat insulation is laid on an upper surface of the non-heated ring, a second portion of the adhesive tape located outwardly of the first portion thereof is located on or above the insulation, a third portion of the adhesive tape located outwardly of the second portion is held by a holder, and the holder is movable up and down relative to the heating table and the non-heated ring by a drive unit.