A heat treatment method is provided for a panel. The panel includes a plastic housing composition, in which semiconductor chips are embedded by their rear sides and edge sides, and the top sides of the semiconductor chips form a coplanar area with the plastic housing composition. The panel is fixed by its underside on a holder, and a temperature gradient (ΔT) is then generated between top side and the underside of the panel. The temperature gradient (ΔT) is then maintained for at least one delimited or selected time period. The panel is then cooled to room temperature (TR).