Abstract: A layout structure of HBTs comprising one or more HBTs, each of which comprises a base electrode, an emitter electrode, and a collector electrode. A passive layer, a first dielectric layer, a collector redistribution layers, one or more emitter copper pillars, and one or more collector copper pillars are formed above the one or more HBTs. The passive layer comprises a collector and an emitter pads. The first dielectric layer has one or more emitter and collector via holes. The emitter copper pillar is disposed on the emitter via hole and forms an electrical connection to the emitter electrode. The collector copper pillar is disposed on the collector redistribution layer and forms electrical connection to the collector electrode. The layout design of the emitter and collector copper pillars is therefore flexible, and the heat dissipation efficiency is improved.

Abstract: An integrated structure of power amplifier and acoustic wave device comprises: a compound semiconductor epitaxial substrate, a power amplifier upper structure formed on a first side of said compound semiconductor epitaxial substrate, and a film bulk acoustic resonator formed on a second side of said compound semiconductor epitaxial substrate; wherein forming an epitaxial structure on a compound semiconductor substrate to form said compound semiconductor epitaxial substrate; wherein said first side of said compound semiconductor epitaxial substrate and said power amplifier upper structure form a power amplifier; said second side of said compound semiconductor epitaxial substrate and said film bulk acoustic resonator form an acoustic wave device; the integrated structure of power amplifier and acoustic wave device on the same compound semiconductor epitaxial substrate is capable of reducing the component size, optimizing the impedance matching, and reducing the signal loss between power amplifier and acoustic w

Abstract: A layout structure of HBTs comprising one or more HBTs, each of which comprises a base electrode, an emitter electrode, and a collector electrode. A passive layer, a first dielectric layer, a collector redistribution layers, one or more emitter copper pillars, and one or more collector copper pillars are formed above the one or more HBTs. The passive layer comprises a collector and an emitter pads. The first dielectric layer has one or more emitter and collector via holes. The emitter copper pillar is disposed on the emitter via hole and forms an electrical connection to the emitter electrode. The collector copper pillar is disposed on the collector redistribution layer and forms electrical connection to the collector electrode. The layout design of the emitter and collector copper pillars is therefore flexible, and the heat dissipation efficiency is improved.

Abstract: A heterojunction bipolar transistor, comprising an elongated base mesa, an elongated base electrode, two elongated emitters, an elongated collector, and two elongated collector electrodes. The elongated base electrode is formed on the base mesa along the long axis of the base mesa, and the base electrode has a base via hole at or near the center of the base electrode. The two elongated emitter are formed on the base mesa respectively at two opposite sides of the base electrode, and each of two emitters has an elongated emitter electrode formed on the emitter. The elongated collector is formed below the base mesa. The two elongated collector electrodes are formed on the collector respectively at two opposite sides of the base mesa.

Abstract: A monolithic compound semiconductor structure is disclosed. The monolithic compound semiconductor structure comprises a substrate, an n-type FET epitaxial structure, an n-type etching-stop layer, a p-type insertion layer, and an npn HBT epitaxial structure, and it can be used to form an FET, an HBT, or a thyristor.

Abstract: An integrated structure of compound semiconductor devices is disclosed. The integrated structure comprises from bottom to top a substrate, a first epitaxial layer, an etching-stop layer, a second epitaxial layer, a sub-collector layer, a collector layer, a base layer, and an emitter layer, in which the first epitaxial layer is a p-type doped layer, the second epitaxial layer is an n-type graded doping layer with a gradually increased or decreased doping concentration, and the sub-collector layer is an n-type doped layer. The integrated structure can be used to form an HBT, a varactor, or an MESFET.

Abstract: A layout structure of HBTs comprising one or more HBTs, each of which comprises a base electrode, an emitter electrode, and a collector electrode. A passive layer, a first dielectric layer, a collector redistribution layers, one or more emitter copper pillars, and one or more collector copper pillars are formed above the one or more HBTs. The passive layer comprises a collector and an emitter pads. The first dielectric layer has one or more emitter and collector via holes. The emitter copper pillar is disposed on the emitter via hole and forms an electrical connection to the emitter electrode. The collector copper pillar is disposed on the collector redistribution layer and forms electrical connection to the collector electrode. The layout design of the emitter and collector copper pillars is therefore flexible, and the heat dissipation efficiency is improved.

Abstract: An improved pseudomorphic high electron mobility transistor (pHEMT) and heterojunction bipolar transistor (HBT) integrated epitaxial structure, in which the structure comprises a substrate, a pHEMT structure, an etching-stop spacer layer, and an HBT structure. The pHEMT structure comprises a buffer layer, a bottom barrier layer, a first channel spacer layer, a channel layer, a second channel spacer layer, a Schottky spacer layer, a Schottky donor layer, a Schottky barrier layer, an etching-stop layer, and at least one cap layer. By introducing the first channel spacer layer and the second channel spacer layer to reduce the density of the dislocations and to reduce the compressive strain in the pseudomorphic channel layer.

Abstract: An integrated structure of compound semiconductor devices is disclosed. The integrated structure comprises from bottom to top a substrate, a first epitaxial layer, an etching-stop layer, a second epitaxial layer, a sub-collector layer, a collector layer, a base layer, and an emitter layer, in which the first epitaxial layer is a p-type doped layer, the second epitaxial layer is an n-type graded doping layer with a gradually increased or decreased doping concentration, and the sub-collector layer is an n-type doped layer. The integrated structure can be used to form an HBT, a varactor, or an MESFET.

Abstract: A monolithic compound semiconductor structure is disclosed. The monolithic compound semiconductor structure comprises a substrate, an n-type FET epitaxial structure, an n-type etching-stop layer, a p-type insertion layer, and an npn HBT epitaxial structure, and it can be used to form an FET, an HBT, or a thyristor.

Abstract: An improved pseudomorphic high electron mobility transistor (pHEMT) and heterojunction bipolar transistor (HBT) integrated epitaxial structure and the fabrication method thereof, in which the structure comprises a substrate, a pHEMT structure, an etching-stop spacer layer, and an HBT structure. The pHEMT's structure comprises a buffer layer, a barrier layer, a first channel spacer layer, a channel layer, a second channel spacer layer, a Schottky barrier layer, an etching-stop layer, and at least one cap layer. The fabrication method of an HBT and a pHEMT are also included.