Abstract: Embodiments of this invention provide a method to fabricate an electrical contact. The method includes providing a substrate of a compound Group III-V semiconductor material having at least one electrically conducting doped region adjacent to a surface of the substrate. The method further includes fabricating the electrical contact to the at least one electrically conducting doped region by depositing a single crystal layer of germanium over the surface of the substrate so as to at least partially overlie the at least one electrically conducting doped region, converting the single crystal layer of germanium into a layer of amorphous germanium by implanting a dopant, forming a metal layer over exposed surfaces of the amorphous germanium layer, and performing a metal-induced crystallization (MIC) process on the amorphous germanium layer having the overlying metal layer to convert the amorphous germanium layer to a crystalline germanium layer and to activate the implanted dopant.

Abstract: A method includes forming a silicon germanium layer, forming a layer comprising carbon and silicon on a top surface of the silicon germanium layer, forming a metal layer above the layer comprising carbon and silicon, and performing a thermal treatment to convert at least the layer comprising carbon and silicon to form a metal silicide layer.

Abstract: A method for layer transfer using a boron-doped silicon germanium (SiGe) layer includes forming a boron-doped SiGe layer on a bulk silicon substrate; forming an upper silicon (Si) layer over the boron-doped SiGe layer; hydrogenating the boron-doped SiGe layer; bonding the upper Si layer to an alternate substrate; and propagating a fracture at an interface between the boron-doped SiGe layer and the bulk silicon substrate. A system for layer transfer using a boron-doped silicon germanium (SiGe) layer includes a bulk silicon substrate; a boron-doped SiGe layer formed on the bulk silicon substrate, such that the boron-doped SiGe layer is located underneath an upper silicon (Si) layer, wherein the boron-doped SiGe layer is configured to propagate a fracture at an interface between the boron-doped SiGe layer and the bulk silicon substrate after hydrogenation of the boron-doped SiGe layer; and an alternate substrate bonded to the upper Si layer.

Abstract: A method for fabrication of a multijunction photovoltaic (PV) cell includes providing a stack comprising a plurality of junctions on a substrate, each of the plurality of junctions having a respective bandgap, wherein the plurality of junctions are ordered from the junction having the smallest bandgap being located on the substrate to the junction having the largest bandgap being located on top of the stack; forming a top metal layer, the top metal layer having a tensile stress, on top of the junction having the largest bandgap; adhering a top flexible substrate to the metal layer; and spalling a semiconductor layer from the substrate at a fracture in the substrate, wherein the fracture is formed in response to the tensile stress in the top metal layer.

Abstract: A method for fabrication of a multijunction photovoltaic (PV) cell includes forming a stack comprising a plurality of junctions on a substrate, each of the plurality of junctions having a respective bandgap, wherein the plurality of junctions are ordered from the junction having the largest bandgap being located on the substrate to the junction having the smallest bandgap being located on top of the stack; forming a metal layer, the metal layer having a tensile stress, on top of the junction having the smallest bandgap; adhering a flexible substrate to the metal layer; and spalling a semiconductor layer from the substrate at a fracture in the substrate, wherein the fracture is formed in response to the tensile stress in the metal layer.

Abstract: A method for spalling a layer from an ingot of a semiconductor substrate includes forming a metal layer on the ingot of the semiconductor substrate, wherein a tensile stress in the metal layer is configured to cause a fracture in the ingot; and removing the layer from the ingot at the fracture. A system for spalling a layer from an ingot of a semiconductor substrate includes a metal layer formed on the ingot of the semiconductor substrate, wherein a tensile stress in the metal layer is configured to cause a fracture in the ingot, and wherein the layer is configured to be removed from the ingot at the fracture.

Abstract: A method for manufacturing a thin film direct bandgap semiconductor active solar cell device comprises providing a source substrate having a surface and disposing on the surface a stress layer having a stress layer surface area in contact with and bonded to the surface of the source substrate. Operatively associating a handle foil with the stress layer and applying force to the handle foil separates the stress layer from the source substrate, and leaves a portion of the source substrate on the stress layer surface substantially corresponding to the area in contact with the surface of the source substrate. The portion is less thick than the source layer. The stress layer thickness is below that which results in spontaneous spalling of the source substrate. The source substrate may comprise an inorganic single crystal or polycrystalline material such as Si, Ge, GaAs, SiC, sapphire, or GaN. In one embodiment the stress layer comprises a flexible material.

Abstract: A method for forming a single-junction photovoltaic cell includes forming a dopant layer on a surface of a semiconductor substrate; diffusing the dopant layer into the semiconductor substrate to form a doped layer of the semiconductor substrate; forming a metal layer over the doped layer, wherein a tensile stress in the metal layer is configured to cause a fracture in the semiconductor substrate; removing a semiconductor layer from the semiconductor substrate at the fracture; and forming the single junction photovoltaic cell using the semiconductor layer. A single-junction photovoltaic cell includes a doped layer comprising a dopant diffused into a semiconductor substrate; a patterned conducting layer formed on the doped layer; a semiconductor layer comprising the semiconductor substrate located on the doped layer on a surface of the doped layer opposite the patterned conducting layer; and an ohmic contact layer formed on the semiconductor layer.

Abstract: A method for forming a heterojunction III-V photovoltaic (PV) cell includes performing layer transfer of a base layer from a wafer of a III-V substrate, the base layer being less than about 20 microns thick; forming an intrinsic layer on the base layer; forming an amorphous silicon layer on the intrinsic layer; and forming a transparent conducting oxide layer on the amorphous silicon layer. A heterojunction III-V photovoltaic (PV) cell includes a base layer comprising a III-V substrate, the base layer being less than about 20 microns thick; an intrinsic layer located on the base layer; an amorphous silicon layer located on the intrinsic layer; and a transparent conducting oxide layer located on the amorphous silicon layer.

Abstract: A method is provided for making a silicon-on-insulator substrate. Such method can include epitaxially growing a highly p-type doped silicon-containing layer onto a major surface of an underlying semiconductor region of a substrate. Subsequently, a non-highly p-type doped silicon-containing layer may be epitaxially grown onto a major surface of the p-type highly-doped epitaxial layer to cover the highly p-type doped epitaxial layer. The overlying non-highly p-type doped epitaxial layer can have a dopant concentration substantially lower than the dopant concentration of the highly p-type doped epitaxial layer. The substrate can then be processed to form a buried oxide layer selectively by oxidizing at least portions of the highly p-type doped epitaxial layer covered by the non-highly p-type doped epitaxial layer, the buried oxide layer separating the overlying monocrystalline semiconductor layer from the underlying semiconductor region.

Abstract: A method is provided for making a silicon-on-insulator substrate. Such method can include epitaxially growing a highly p-type doped silicon-containing layer onto a major surface of an underlying semiconductor region of a substrate. Subsequently, a non-highly p-type doped silicon-containing layer may be epitaxially grown onto a major surface of the p-type highly-doped epitaxial layer to cover the highly p-type doped epitaxial layer. The overlying non-highly p-type doped epitaxial layer can have a dopant concentration substantially lower than the dopant concentration of the highly p-type doped epitaxial layer. The substrate can then be processed to form a buried oxide layer selectively by oxidizing at least portions of the highly p-type doped epitaxial layer covered by the non-highly p-type doped epitaxial layer, the buried oxide layer separating the overlying monocrystalline semiconductor layer from the underlying semiconductor region.

Abstract: Disclosed herein is a method of preparing strained silicon comprising annealing a carbon-doped silicon-germanium (SiGe:C) alloy containing region disposed adjacent to a silicon region, wherein the lattice constant of the SiGe:C alloy after annealing is greater than that of the SiGe:C alloy prior to annealing. The method can be used to prepare articles including metal oxide semiconductor field effect transistor (MOSFET) devices.

Abstract: A method of forming a low-defect, substantially relaxed SiGe-on-insulator substrate material is provided. The method includes first forming a Ge-containing layer on a surface of a first single crystal Si layer which is present atop a barrier layer that is resistant to Ge diffusion. A heating step is then performed at a temperature that approaches the melting point of the final SiGe alloy and retards the formation of stacking fault defects while retaining Ge. The heating step permits interdiffusion of Ge throughout the first single crystal Si layer and the Ge-containing layer thereby forming a substantially relaxed, single crystal SiGe layer atop the barrier layer. Moreover, because the heating step is carried out at a temperature that approaches the melting point of the final SiGe alloy, defects that persist in the single crystal SiGe layer as a result of relaxation are efficiently annihilated therefrom.

Abstract: A substrate for a semiconductor device is disclosed including, in one embodiment, a plurality of semiconductor-on-insulator (SOI) wafers bonded to one another in a single stack. A distal end of the stack includes a first SOI region with a first semiconductor layer having a thickness and a first surface orientation. A surface of the single stack may further include a non-SOI region and/or at least one second SOI region. The non-SOI region may include bulk silicon that extends through all of the insulator layers of the single stack and has a thickness different than that of the first silicon layer. Each second SOI region has a second semiconductor layer having a thickness different than that of the first semiconductor layer and/or a different surface orientation than the first surface orientation. The substrate thus allows formation of different devices on optimal substrate regions that may include different surface orientations and/or different thicknesses and/or different bulk or SOI structures.

Abstract: A method that allows for uniform, simultaneous epitaxial growth of a semiconductor material on dissimilarly doped semiconductor surfaces (n-type and p-type) that does not impart substrate thinning via a novel surface preparation scheme, as well as a structure that results from the implementation of this scheme into the process integration flow for integrated circuitry are provided. The method of the present invention can by used for the selective or nonselective epitaxial growth of semiconductor material from the dissimilar surfaces.

Abstract: The present invention provides a method for forming low-defect density changed-orientation Si by amorphization/templated recrystallization (ATR) processes in which regions of Si having a first crystal orientation are amorphized by ion implantation and then recrystallized into the orientation of a template layer having a different orientation. More generally, the invention relates to the high temperature annealing conditions needed to eliminate the defects remaining in Si-containing single crystal semiconductor materials formed by ion-implant-induced amorphization and templated recrystallization from a layer whose orientation may be the same or different from the amorphous layer's original orientation. The key component of the inventive method is a thermal treatment for minutes to hours in the the temperature range 1250-1330° C. to remove the defects remaining after the initial recrystallization anneal.

Abstract: A method for fabricating germanium-on-insulator (GOI) substrate materials, the GOI substrate materials produced by the method and various structures that can include at least the GOI substrate materials of the present invention are provided. The GOI substrate material include at least a substrate, a buried insulator layer located atop the substrate, and a Ge-containing layer, preferably pure Ge, located atop the buried insulator layer. In the GOI substrate materials of the present invention, the Ge-containing layer may also be referred to as the GOI film. The GOI film is the layer of the inventive substrate material in which devices can be formed.

Abstract: A semiconductor-containing heterostructure including, from bottom to top, a III-V compound semiconductor buffer layer, a III-V compound semiconductor channel layer, a III-V compound semiconductor barrier layer, and an optional, yet preferred, III-V compound semiconductor cap layer is provided. The barrier layer may be doped, or preferably undoped. The III-V compound semiconductor buffer layer and the III-V compound semiconductor barrier layer are comprised of materials that have a wider band gap than that of the III-V compound semiconductor channel layer. Since wide band gap materials are used for the buffer and barrier layer and a narrow band gap material is used for the channel layer, carriers are confined to the channel layer under certain gate bias range. The inventive heterostructure can be employed as a buried channel structure in a field effect transistor.

Abstract: Techniques for the fabrication of semiconductor devices are provided. In one aspect, a layer transfer structure is provided. The layer transfer structure comprises a carrier substrate having a porous region with a tuned porosity in combination with an implanted species defining a separation plane therein In another aspect, a method of forming a layer transfer structure is provided. In yet another aspect, a method of forming a thee dimensional integrated structure is provided.

Abstract: This invention teaches methods of combining ion implantation steps with in situ or ex situ heat treatments to avoid and/or minimize implant-induced amorphization (a potential problem for source/drain (S/D) regions in FETs in ultrathin silicon on insulator layers) and implant-induced plastic relaxation of strained S/D regions (a potential problem for strained channel FETs in which the channel strain is provided by embedded S/D regions lattice mismatched with an underlying substrate layer). In a first embodiment, ion implantation is combined with in situ heat treatment by performing the ion implantation at elevated temperature. In a second embodiment, ion implantation is combined with ex situ heat treatments in a “divided-dose-anneal-in-between” (DDAB) scheme that avoids the need for tooling capable of performing hot implants.