According to an aspect of present disclosure, a phase shifter for providing a desired phase shift to a very high frequency signal fabricated as part of the an integrated circuit comprises a first coil segment and a second coil segment together forming an inductor of first inductance value, a first capacitor of first capacitance value electrically connected parallel the inductor, a second capacitor of second capacitance value electrically connected between the first coil segment and the second coil segment and a resistor of a first resistance value electrically connected parallel to the second capacitor, in that, the inductor, first capacitor, second capacitor and the resistor together operative as a phase shifter such that when a input signal of a first frequency is presented across the first capacitor, the output signal across the resistor is phase shifted version of the input signal shifted in phase by a first angle.

A filter includes a circuit including a resistor, a positive capacitor, and a negative capacitor connected in series to accept the same current. The filter also includes an input terminal to accept an input voltage across the circuit and an output terminal to deliver an output voltage taken across the resistor or the positive capacitor.

An IC includes an RC filter, a doped layer under a first dielectric layer, a polysilicon layer on the first dielectric layer providing a polysilicon plate for a capacitor of the filter, and gate(s) for MOSFET(s). A second dielectric layer is on the polysilicon plate. An input contact is on one end of the polysilicon plate and an output contact is on the opposite end. A metal layer includes metal providing contact to at least input contact and metal providing contact to the output contact. Analog circuitry includes the MOSFET having an I/O node coupled to the RC filter.

In a first approach, a reconfigurable radio frequency (RF) filtering module includes a phase-change material (PCM) RF switch bank and an RF filter bank. Each RF filter in the RF filter bank is capable to be engaged and disengaged by a PCM RF switch in the PCM RF switch bank. In a second approach, a tunable RF filter includes PCM RF switches and a capacitor and/or an inductor. Each of the capacitor and/or inductor is capable to be engaged and disengaged by at least one PCM RF switch of the PCM RF switches. In a third approach, an adjustable passive component includes multiple segments and a PCM RF switch. A selectable segment in the multiple segments is capable to be engaged and disengaged by the PCM RF switch. In all approaches, each PCM RF switch includes a PCM and a heating element transverse to the PCM.

Layer structures for RF filters can be fabricated using rare earth oxides and epitaxial aluminum nitride, and methods for growing the layer structures. A layer structure can include an epitaxial crystalline rare earth oxide (REO) layer over a substrate, a first epitaxial electrode layer over the crystalline REO layer, and an epitaxial piezoelectric layer over the first epitaxial electrode layer. The layer structure can further include a second electrode layer over the epitaxial piezoelectric layer. The first electrode layer can include an epitaxial metal. The epitaxial metal can be single-crystal. The first electrode layer can include one or more of a rare earth pnictide, and a rare earth silicide (RESi).

An integrated circuit (IC) device includes a first resistive strip having an input terminal and an output terminal. The IC device further includes a second resistive strip having a terminal coupled to a voltage. The second resistive strip may be coplanar with the first resistive strip. The IC device further includes a capacitor formed by the first resistive strip and the second resistive strip.

High aspect ratio passive electrical components are presented formed from a single-piece silicon (Si) substrate having a textured surface with at least one high aspect ratio structure. The high aspect ratio structure includes a Si core having a width (C.sub.X), a height (C.sub.Z), and a minimum aspect ratio of C.sub.Z-to-C.sub.X of at least 5:1. An electrical conductor layer overlies the Si core. The electrical component may be a capacitor, inductor, or transmission line. In the case of a capacitor, the substrate textured first surface is made up of a plurality of adjacent high aspect ratio conductor-dielectric-Si (CDS) structures. Each CDS structure includes: a Si core, a dielectric layer overlying the Si core, and an electrical conductor layer overlying the dielectric layer. The Si cores may be formed in the geometry of parallel ridges, columns, or as a honeycomb. Each Si core comprises at least 90% of the CDS structure height.

An integrated device that includes a substrate, a first interconnect over the substrate and a second interconnect comprising a first portion and a second portion. The integrated device further comprising a first dielectric layer between the first interconnect and the first portion of the second interconnect such that the first interconnect vertically overlaps with the first dielectric layer and the first portion of the second interconnect. The integrated device also includes a second dielectric layer formed over the substrate. The first interconnect, the first dielectric layer and the first portion of the second interconnect are configured to operate as a capacitor. The first portion and the second portion of the second interconnect are configured to operate as an inductor.

A radio frequency (RF) front-end (RFFE) device includes a die having a front-side dielectric layer on an active device. The active device is on a first substrate. The RFFE device also includes a microelectromechanical system (MEMS) device. The MEMS device is integrated on the die at a different layer than the active device. The MEMS device includes a cap layer composed of a cavity in the front-side dielectric layer of the die. The cavity in the front-side dielectric layer is between the first substrate and a second substrate. The cap is coupled to the front-side dielectric layer.

Embodiments of the present invention provide an inductively coupled filter and a WiFi module. The inductively coupled filter includes a first circuit, where the first circuit is disposed on a first substrate; and a second circuit, where the second circuit is disposed on a second substrate; and the first substrate and the second substrate are disposed opposite to each other, so that a coil inductor in the first circuit and a coil inductor in the second circuit form a mutual induction structure. In the inductively coupled filter in the embodiments of the present invention, the coil inductors are disposed on two substrates respectively. This can reduce an area occupied by the inductively coupled filter on each package substrate.