A terahertz device of the present invention includes a terahertz element generating an electromagnetic wave, a dielectric including a dielectric material and surrounding the terahertz element, a gas space including a gas, and a reflecting film serving as a reflecting portion. The reflecting film includes a portion opposing the terahertz element through the dielectric and the gas space and reflecting the electromagnetic wave toward a direction, wherein the electromagnetic wave is generated from the terahertz element and transmitted through the dielectric and the gas space. In addition, the refractive index of the dielectric is lower than the refractive index of the terahertz element and is higher than the refractive index of the gas in the gas space.

In an embodiment, a structure includes: a processor device including logic devices; a first memory device directly face-to-face bonded to the processor device by metal-to-metal bonds and by dielectric-to-dielectric bonds; a first dielectric layer laterally surrounding the first memory device; a redistribution structure over the first dielectric layer and the first memory device, the redistribution structure including metallization patterns; and first conductive vias extending through the first dielectric layer, the first conductive vias connecting the metallization patterns of the redistribution structure to the processor device.

A semiconductor device has a plurality of semiconductor die. A first prefabricated insulating film is disposed over the semiconductor die. A conductive layer is formed over the first prefabricated insulating film. An interconnect structure is formed over the semiconductor die and first prefabricated insulating film. The first prefabricated insulating film is laminated over the semiconductor die. The first prefabricated insulating film includes glass cloth, glass fiber, or glass fillers. The semiconductor die is embedded within the first prefabricated insulating film with the first prefabricated insulating film covering first and side surfaces of the semiconductor die. The interconnect structure is formed over a second surface of the semiconductor die opposite the first surface. A portion of the first prefabricated insulating film is removed after disposing the first prefabricated insulating film over the semiconductor die. A second prefabricated insulating film is disposed over the first prefabricated insulating film.

A method of batch soldering includes: forming a soldered joint between a metal region of a first semiconductor die and a metal region of a substrate using a solder preform via a soldering process which does not apply pressure directly to the first semiconductor die, the solder preform having a maximum thickness of 30 μm and a lower melting point than the metal regions; setting a soldering temperature of the soldering process so that the solder preform melts and fully reacts with the metal region of the first semiconductor die and the metal region of the substrate to form one or more intermetallic phases throughout the entire soldered joint, each intermetallic phase having a melting point above the preform melting point and the soldering temperature; and soldering a second semiconductor die to the same or different metal region of the substrate, without applying pressure directly to the second semiconductor die.

An electronic package structure is provided. The electronic packaging structure includes a substrate, a conductive layer disposed on the substrate, an intermetallic compound disposed on the conductive layer, a stress buffering material disposed on the substrate and adjacent to the conductive layer, and an electronic device disposed on the conductive layer and the stress buffering material. The intermetallic compound is disposed between the electronic device and the conductive layer, between the electronic device and the stress buffering material, between the substrate and the stress buffering material, and between the conductive layer and the stress buffering material. A maximum thickness of the intermetallic compound disposed between the electronic device and the stress buffering material, between the substrate and the stress buffering material, and between the conductive layer and the stress buffering material is greater than the thickness of the intermetallic compound disposed between the electronic device and the conductive layer.

A radio frequency module includes a mounting substrate, a low-noise amplifier including an amplifying element and amplifying a radio frequency signal, and an impedance matching circuit including an integrated first inductor, in which the first inductor is connected to an input terminal of the low-noise amplifier, the low-noise amplifier and the impedance matching circuit are laminated in a direction perpendicular to a main surface of the mounting substrate, and a first multilayer body on which the low-noise amplifier and the impedance matching circuit are laminated is mounted on the main surface.

A semiconductor device includes a semiconductor element, a first lead supporting the semiconductor element, a second lead separated from the first lead, and a connection lead electrically connecting the semiconductor element to the second lead. The connection lead has an end portion soldered to the second lead. This connection-lead end portion has a first surface facing the semiconductor element and a second surface opposite to the first surface. The second lead is formed with a recess that is open toward the semiconductor element. The recess has a side surface facing the second surface of the connection-lead end portion. A solder contact area of the second surface of the connection-lead end portion is larger than a solder contact area of the first surface of the connection-lead end portion.

Transformer-driven power switch devices are provided for switching high currents. These devices include power switches, such as Gallium Nitride (GaN) transistors. Transformers are used to transfer both control timing and power for controlling the power switches. These transformers may be coreless, such that they may be integrated within a silicon die. Rectifiers, pulldown control circuitry, and related are preferably integrated in the same die as a power switch, e.g., in a GaN die, such that a transformer-driven switch device is entirely comprised on a silicon die and a GaN die, and does not necessarily require a (large) cored transformer, auxiliary power supplies, or level shifting circuitry.

A method of joining a semiconductor die to a substrate includes: applying a solder preform to a metal region of the semiconductor die or to a metal region of the substrate, the solder preform having a maximum thickness of 30 μm and a lower melting point than both metal regions; forming a soldered joint between the metal region of the semiconductor die and the metal region of the substrate via a diffusion soldering process and without applying pressure directly to the die; and setting a soldering temperature of the diffusion soldering process so that the solder preform melts and fully reacts with the metal region of the semiconductor die and the metal region of the substrate to form one or more intermetallic phases throughout the entire soldered joint, each intermetallic phase having a melting point above the melting point of the preform and the soldering temperature.

A method of batch soldering includes: forming a soldered joint between a metal region of a first semiconductor die and a metal region of a substrate using a solder preform via a soldering process which does not apply pressure directly to the first semiconductor die, the solder preform having a maximum thickness of 30 μm and a lower melting point than the metal regions; setting a soldering temperature of the soldering process so that the solder preform melts and fully reacts with the metal region of the first semiconductor die and the metal region of the substrate to form one or more intermetallic phases throughout the entire soldered joint, each intermetallic phase having a melting point above the preform melting point and the soldering temperature; and soldering a second semiconductor die to the same or different metal region of the substrate, without applying pressure directly to the second semiconductor die.