Electronic package with improved thermal performance

The present invention provides an electronic package with improved thermal performance. The electronic package includes a thermally conductive heat dissipator and a transmission circuit. The thermally conductive heat dissipator has a first surface and a second surface with the first surface of the thermally conductive heat dissipator including extended portions. The transmission circuit defines a cavity, and includes a first conductive layer, a second conductive layer, and a dielectric layer sandwiched between the first and second conductive layers. The second conductive layer is coupled to the second surface of the thermally conductive heat dissipator and the cavity extends through the transmission circuit to the thermally conductive heat dissipator.