Encapsulating method of substrate based electronic device

In a method of encapsulating a substrate-based electronic device which comprises placing the device in an encapsulating mold, said mold including a cavity, a runner, a gate and a pot;

• supplying an encapsulant to the pot, liquidizing the encapsulant in the pot and causing the liquidized encapsulant to flow into the cavity through the runner and gate to fill the cavity containing the semiconductor device to cause encapsulation, allowing the encapsulant to substantially solidify, opening said mold and removing the encapsulated substrate-based electronic device, wherein the improvement comprises placing a degate shim on the substrate of said substrate-based electronic device located at the position where the runner passes through in order to allow the degate shim to allow substantially no contact of the encapsulant with the substrate during injection of the encapsulant, wherein said degate shim is a mold heat-resisting piece shaped matter, larger than the range of said runner located on said substrate and completely covers said range, and wherein the thickness of said degate shim does not exceed 0.05 mm.