RF transistor package with capacitor
AssigneeFujitsu Limited
InventorsYutaka Hirano, Masanobu Itoh, Akira Izumi, Yoshikazu Dooi
Life of this patent
Estimating the term…
Abstract
A semiconductor device comprising a conductive layer; an insulting layer mounted on the conductive layer and having an opening; terminals deposited on the insulating layer; an active semiconductor element mounted on the conductive layer or the insulating layer, and; a capacitor mounted on the conductive layer. In this device, a path between the semiconductor element and the capacitor is very short and the conductive layer serves as a heat sink.
Claims7
A high frequency semiconductor amplifier requiring a bypass capacitance for high frequency currents and a heat sink for high power operation, comprising:
- a first, heat sink conductive layer having a main surface and having an electrical ground connection;
- an insulating layer of a first predetermined thickness formed on the main surface of the heat sink conductive layer and having a generally, centrally located opening therein exposing therethrough a corresponding portion of the main surface of the heat sink conductive layer;
- a second conductive layer formed on the exposed portion of the main surface of the first, heat sink conductive layer and of a second predetermined thickness;
- an active semiconductor element, comprising a field effect transistor having source, gate and drain regions and corresponding connection points, mounted on and bonded to the second conductive layer and of a third predetermined thickness;
- a bypass capacitor having top and bottom electrodes and of a fourth predetermined thickness, mounuted on and bonded to the second conductive layer in closely spaced relationship to the semiconductor element and defining a first alignment direction relatively to the semiconductor element and the opening in the insulting layer, the bottom electrode of the bypass capacitor being electrically connected to the second conductive layer, the first heat sink conductive layer and the electrical ground connection;
- each of the third and fourth predetermined thickness of the active semiconductor element and the bypass capacitor, respectively, being substantially less than either of the first and second predetermined thickness of the first, heat sink conductive layer and the insulating layer, respectively;
- a first metallized layer formed on the insulating layer and aligned in the first alignment direction, with the bypass capacitor positioned between the first metallized layer and the semiconductor element;
- means for providing a series electrical connection of the source connection point of the semiconductor element, the top electrode of the bypass capacitor, and the first metallized layer;
- second and third metallized layers formed on the insulating layer in a second alignment direction, transverse to the first alignment direction, and aligned with and spaced apart from the semiconductor element by at least the opening in the insulating layer;
- means for providing an electrical connection between the drain connection point of the semiconductor element and the second metallized layer;
- means for providing an electrical connection between the gate connection point of the semiconductor element and the third metallized layer;
- and
- a source terminal plate oriented in the first alignment direction and bonded to the first metallized layer, and drain and gate terminal plates oriented in the second alignment direction and respectively bonded to the second and third metallized layers, the source, drain and gate terminal plates extending laterally from the first heat sink conductive layer and the insulating layer to provide external electrical connections to the amplifier.
The device of cliam 2, wherein the parasitic inductance for propagation of said high frequency current between the source and said top electrode of the capacitor is effectively limited by the length of the first connecting wire in comparison to the length and respective parasitic inductance of said second wire.
Dependencies are inferred from the claim text.