Abstract: A casing structure with functionality of effective thermal management is disclosed, which consists of a casing member, a low thermal conductivity medium, a second heat spreader, and a first heat spreader. When a user operates the electronic device, heat generated from CPU and/or GPU is transferred to the second heat spreader via the first heat spreader, and then is two-dimensionally spread in the second heat spreader. Consequently, the heat is dissipated away from the casing member to air due to the outstanding thermal radiation ability of the casing member. The low thermal conductivity medium is adopted for controlling a heat transfer of heat transferring paths from the heat source and ends to the casing member. By applying the casing structure in an electronic device by a form of a top casing and/or a back casing, an outer surface temperature of the casing member can be well controlled.

Abstract: A method for fabricating a high electron mobility transistor (HEMT) includes the steps of forming a buffer layer on a substrate, forming a barrier layer on the buffer layer, forming a p-type semiconductor layer on the barrier layer, forming a gate electrode layer on the p-type semiconductor layer, and patterning the gate electrode layer to form a gate electrode. Preferably, the gate electrode includes an inclined sidewall.

Abstract: A polyhedral is provided. The surface of the polyhedral is formed by connection of a plane having a plurality of hexagons and a plane having a plurality of quadrilaterals. There are six hexagonal connected to form a ring covering the surface of the polyhedral. On the surface of the polyhedral, any two connected hexagons form a contained angle of 120 degrees. The polyhedral has a light source and an electric control circuit disposed therein. A plurality of polyhedron can be connected into a multi-media light assembly having a numerical display function or a clock function.