Abstract:
A III-V compound semiconductor heterostructure grown on a substrate is described. The heterostructure includes a first semiconductor layer, wherein the first layer semiconductor layer is a compound semiconductor layer with (III) (V), wherein (III) represents one or more group-III elements and (V) represents one or more group-V elements, an intermediate layer on the first semiconductor layer, wherein the intermediate layer is a compound semiconductor layer with (III) x>1 (V) 2-x , and wherein the intermediate layer has a thickness of 10 monolayers or below, and a second semiconductor layer, wherein the first layer semiconductor layer is a compound semiconductor layer with (III) 1 (V) 1
Abstract:
Isoelectronic co-doping of semiconductor compounds and alloys with acceptors and deep donors is used to decrease bandgap, to increase concentration of the dopant constituents in the resulting alloys, and to increase carrier mobilities lifetimes. For example, Group III-V compounds and alloys, such as GaAs and GaP, are isoelectronically co-doped with, for example, B and Bi, to customize solar cells, and other semiconductor devices. Isoelectronically co-doped Group II-VI compounds and alloys are also included.
Abstract:
A graphene base transistor comprises on a semiconductor substrate surface (102) an emitter pillar (110) and an emitter-contact pillar (112.1, 112.2), which extend from a pillar foundation (108) in a vertical direction. A dielectric filling layer (114) laterally embeds the emitter pillar (110) and the emitter-contact pillar (112.1, 122.2) above the pillar foundation (108). The dielectric filling layer (114) has an upper surface (S) that is flush with a top surface of the emitter pillar (110) and with the at least one base-contact arm (112) of a base-contact structure (116). A graphene base (118) forms a contiguous layer between a top surface of the emitter pillar (110) and atop surface of the base-contact arm (116.2, 116.3). A collector stack (120) and the base (118) have the same lateral extension parallel to the substrate surface (102) and perpendicular to those edges of the top surface of the emitter pillar (110) and the base-contact arm (116.2, 116.3) that face each other.
Abstract:
This disclosure describes a switch having a collector, base, emitter, and an intrinsic region between the collector and base. The intrinsic region increases the efficiency of the switch and reduces losses. The collector, base, and emitter each have respective terminals, and an AC component of current passing through the base terminal is greater than an AC component of current passing through the emitter terminal. Additionally, in an on- state a first alternating current between the base and collector terminals is greater than a second alternating current between the collector and emitter terminals. In other words, AC passes primarily between collector and base as controlled by a DC current between the base and emitter.
Abstract:
Disclosed are structures and methods related to a barrier layer for metallization of a selected semiconductor such as indium gallium phosphide (InGaP). In some embodiments, the barrier layer can include tantalum nitride (TaN). Such a barrier layer can provide desirable features such as barrier functionality, improved adhesion of a metal layer, reduced diffusion, reduced reactivity between the metal and InGaP, and stability during the fabrication process. In some embodiments, structures formed in such a manner can be configured as an emitter of a gallium arsenide (GaAs) heterojunction bipolar transistor (HBT) or an on-die high-value capacitance element. In some embodiments, some of the foregoing structures can be configured as a capacitance element having a capacitance value representative of the thickness of the emitter layer. Accordingly, monitoring of such a capacitance value during various HBT processes allows monitoring of the integrity of the emitter layer.
Abstract:
In the present invention a metal oxide or nitride compound which is a wide-i band-gap semiconductor abuts a silicon, germanium, or alloy of silicon and/or germanium of the opposite conductivity type to form a p-n heteroj unction. This p-n heteroj unction can be used to advantage in various devices. In preferred embodiments, one terminal of a vertically oriented p-i-n heterojunction diode is a metal oxide or nitride layer (118), while the rest of the diode is formed of a silicon or silicon-germanium resistor; for example a diode may include a heavily doped n-type silicon region (4), an intrinsic silicon region (6), and a nickel oxide layer (118) serving as the p-type terminal. Many of these metal oxides and nitrides exhibit resistivity-switching behavior, and such a heterojunction diode can be used in a nonvolatile memory cell, for example in a monc-lithic three dimensional memory array.