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.

An electrical device includes a counterdoped heterojunction selected from a group consisting of a pn junction or a p-i-n junction. The counterdoped junction includes a first semiconductor doped with one or more n-type primary dopant species and a second semiconductor doped with one or more p-type primary dopant species. The device also includes a first counterdoped component selected from a group consisting of the first semiconductor and the second semiconductor. The first counterdoped component is counterdoped with one or more counterdopant species that have a polarity opposite to the polarity of the primary dopant included in the first counterdoped component. Additionally, a level of the n-type primary dopant, p-type primary dopant, and the one or more counterdopant is selected to the counterdoped heterojunction provides amplification by a phonon assisted mechanism and the amplification has an onset voltage less than 1 V.

A laser diode including a double heterostructure comprising a top layer, a buffer layer formed on a substrate, and an intrinsic active layer formed between the top layer and the buffer layer. The top layer and the buffer layer have opposite types of conductivity. The active layer has a bandgap smaller than that of the buffer layer or the top layer. The double heterostructure includes Ge, SiGe, GeSn, and/or SiGeSn materials.

Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.

Wafer bonded GaN monolithic integrated circuits and methods of manufacture of wafer bonded GaN monolithic integrated circuits and their related structures for electronic and photonic integrated circuits and for multi-functional integrated circuits, are described herein. Other embodiments are also disclosed herein.

An electrical device includes a counterdoped heterojunction selected from a group consisting of a pn junction or a p-i-n junction. The counterdoped junction includes a first semiconductor doped with one or more n-type primary dopant species and a second semiconductor doped with one or more p-type primary dopant species. The device also includes a first counterdoped component selected from a group consisting of the first semiconductor and the second semiconductor. The first counterdoped component is counterdoped with one or more counterdopant species that have a polarity opposite to the polarity of the primary dopant included in the first counterdoped component. Additionally, a level of the n-type primary dopant, p-type primary dopant, and the one or more counterdopant is selected to the counterdoped heterojunction provides amplification by a phonon assisted mechanism and the amplification has an onset voltage less than 1 V.

Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.

A laser includes a network of micro-ridges of quantum cascade lasers of preset emission wavelength, the micro-ridges, which are of preset widths, forming active zones of refractive index n.sub.za that are spaced apart from each other by an inter-ridge material of refractive index n.sub.e, with n.sub.za<n.sub.e. The inter-ridge material is a group-IV material is also provided.

An electrical device includes a counterdoped heterojunction selected from a group consisting of a pn junction or a p-i-n junction. The counterdoped junction includes a first semiconductor doped with one or more n-type primary dopant species and a second semiconductor doped with one or more p-type primary dopant species. The device also includes a first counterdoped component selected from a group consisting of the first semiconductor and the second semiconductor. The first counterdoped component is counterdoped with one or more counterdopant species that have a polarity opposite to the polarity of the primary dopant included in the first counterdoped component. Additionally, a level of the n-type primary dopant, p-type primary dopant, and the one or more counterdopant is selected to the counterdoped heterojunction provides amplification by a phonon assisted mechanism and the amplification has an onset voltage less than 1 V.

Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.