One aspect of this disclosure is a power amplifier module that includes a power amplifier, a semiconductor resistor, a tantalum nitride terminated through wafer via, and a conductive layer electrically connected to the power amplifier. The semiconductor resistor can include a resistive layer that includes a same material as a layer of a bipolar transistor of the power amplifier. A portion of the conductive layer can be in the tantalum nitride terminated through wafer via. The conductive layer and the power amplifier can be on opposing sides of a semiconductor substrate. Other embodiments of the module are provided along with related methods and components thereof.

A device assembly includes a functional substrate having one or more electronic components formed there. The functional substrate has a cavity extending from a first surface toward a second surface of the functional substrate at a location that lacks the electronic components. The device assembly further includes a semiconductor die placed within the cavity with a pad surface of the semiconductor die being opposite to a bottom of the cavity. The functional substrate may be formed utilizing a first fabrication technology and the semiconductor die may be formed utilizing a second fabrication technology that differs from the first fabrication technology.

At least one transistor is arranged on a substrate. A collector layer and a base layer of the transistor compose a collector mesa having a substantially mesa shape and the collector mesa has side faces tilting with respect to the substrate so that the dimension of a top face in a first direction of a plane of the substrate is smaller than the dimension of a bottom face therein. A first insulating film covering the transistor is arranged on the substrate. A first-layer emitter line that extends from an area overlapped with the top face of the collector mesa to areas overlapped with at least part of the tilting side faces of the collector mesa in a plan view is arranged on the first insulating film. A second-layer emitter line and an emitter bump are arranged on the first-layer emitter line.

A semiconductor device includes at least one transistor disposed on or in a substrate. The transistor is a bipolar transistor including an emitter, a base, and a collector, or a field-effect transistor including a source, a gate, and a drain. At least one first bump connected to the emitter or the source is disposed on the substrate. Furthermore, at least three second bumps connected to the collector or the drain are disposed on the substrate. In plan view, a geometric center of the at least one first bump is located inside a polygon whose vertices correspond to geometric centers of the at least three second bumps.

Methods of manufacturing heterojunction bipolar transistors are described herein. An exemplary method can include providing an emitter/base stack comprising a substrate, a base over the substrate, and/or an emitter over the base. The exemplary method further can include forming a collector. The exemplary method also can include wafer bonding the base to the collector. Other embodiments are also disclosed herein.

One aspect of this disclosure is a power amplifier system that includes a control interface, a power amplifier, a passive component, and a bias circuit. The power amplifier and the passive component can be on a first die. The bias circuit can be on a second die. The control interface can operate as a serial interface or as a general purpose input/output interface. The power amplifier can be controllable based at least partly on an output signal from the control interface. The bias circuit can generate a bias signal based at least partly on an indication of the electrical property of the passive component. Other embodiments of the system are provided along with related methods and components thereof.

A semiconductor device includes an HBT; emitter wiring which is connected to an emitter electrode of the HBT and covers the HBT; a passivation film having an opening on the HBT in plan view; a UBM layer which is connected to the emitter wiring through the opening and made of a refractory metal with a thickness of 300 nm or more; and a pillar bump which is arranged on the UBM layer and includes a metal post and a solder layer. The UBM layer serves as a stress relaxation layer, thereby relaxing stress on the HBT due to a difference in thermal expansion coefficient between a GaAs-based material of each layer constituting the HBT and the pillar bump.

A radio frequency module includes: a first power amplifier and a second power amplifier on a first principal surface of a module board; external-connection terminals on a second principal surface; and a first via-conductor and a second via-conductor apart from each other inside of the board. One end of the first via-conductor is connected to a ground electrode of the first power amplifier, and the other end is connected to a first external-connection terminal. One end of the second via-conductor is connected to a ground electrode of the second power amplifier, and the other end is connected to a second external-connection terminal. The second via-conductor penetrates the board in a normal direction of the first principal surface, and the first via-conductor includes columnar conductors cascaded with central axes thereof displaced in the normal direction and has no region where the columnar conductors overlap in a plan view of the board.

A semiconductor device includes a semiconductor substrate, a transistor, and a first harmonic termination circuit. The transistor is formed at the semiconductor substrate. The transistor amplifies an input signal supplied to an input end and outputs an amplified signal through an output end. The first harmonic termination circuit attenuates a harmonic component included in the amplified signal. The first harmonic termination circuit is formed at the semiconductor substrate such that one end of the first harmonic termination circuit is connected to the output end of the transistor and the other end of the first harmonic termination circuit is connected to a ground end of the transistor.

A semiconductor device includes a semiconductor substrate, a transistor, and a first harmonic termination circuit. The transistor is formed at the semiconductor substrate. The transistor amplifies an input signal supplied to an input end and outputs an amplified signal through an output end. The first harmonic termination circuit attenuates a harmonic component included in the amplified signal. The first harmonic termination circuit is formed at the semiconductor substrate such that one end of the first harmonic termination circuit is connected to the output end of the transistor and the other end of the first harmonic termination circuit is connected to a ground end of the transistor.