Abstract: An antigen-specific T-cell response to alloantigen, tissue-specific antigen (e.g., islet antigen or other autoantigens involved in autoimmune disease), or self (or host) antigen is detected at an early stage of graft rejection or recurrent autoimmunity. An increase in cytotoxic lymphocyte gene (CLG) expression in peripheral blood is a risk factor for development of deleterious immune responses, which may be confirmed by functional assays. For example, the distinction between production of regulatory or inflammatory cytokines by T cells may dissect the type of immune response which is being induced: the survival of transplanted islet cells used to treat type 1 diabetes may be monitored, loss of the transplant by graft rejection (i.e., an alloantigen target) may be distinguished from autoimmune disease (i.e., a self or host antigen target).

Abstract: A structure and method of fabricating a high-mobility semiconductor layer structure and field-effect transistor (MODFET) that includes a high-mobility conducting channel, while at the same time, maintaining counter doping to control deleterious short-channel effects. The MODFET design includes a high-mobility conducting channel layer wherein the method allows the counter doping to be formed using a standard technique such as ion implantation, and further allows the high-mobility channel to be in close proximity to the counter doping without degradation of the mobility.

Abstract: A method for fabricating a semiconductor substrate includes epitaxially growing an elemental semiconductor layer on a compound semiconductor substrate. An insulating layer is deposited on top of the elemental semiconductor layer, so as to form a first substrate. The first substrate is wafer bonded onto a monocrystalline Si substrate, such that the insulating layer bonds with the monocrystalline Si substrate. A semiconductor device includes a monocrystalline substrate, and a dielectric layer formed on the monocrystalline substrate. A semiconductor compound is formed on the dielectric layer and an elemental semiconductor material formed in proximity of the semiconductor compound and lattice-matched to the semiconductor compound.

Abstract: A structure, and a method for fabricating the structure, for the isolation of electronic devices is disclosed. The electronic devices are processed in substrates comprising a SiGe based layer underneath a strained Si layer. The isolation structure comprises a trench extending downward from the substrate top surface and penetrating into the SiGe based layer, forming a sidewall in the substrate. An epitaxial Si liner is selectively deposited onto the trench sidewall, and subsequently thermally oxidized. The trench is filled with a trench dielectric, which protrudes above the substrate top surface.

Abstract: The invention addresses the problem of creating a high-speed, high-efficiency photodetector that is compatible with Si CMOS technology. The structure consists of a Ge absorbing layer on a thin SOI substrate, and utilizes isolation regions, alternating n- and p-type contacts, and low-resistance surface electrodes. The device achieves high bandwidth by utilizing a buried insulating layer to isolate carriers generated in the underlying substrate, high quantum efficiency over a broad spectrum by utilizing a Ge absorbing layer, low voltage operation by utilizing thin a absorbing layer and narrow electrode spacings, and compatibility with CMOS devices by virtue of its planar structure and use of a group IV absorbing material. The method for fabricating the photodetector uses direct growth of Ge on thin SOI or an epitaxial oxide, and subsequent thermal annealing to achieve a high-quality absorbing layer.

Abstract: A structure and method of fabricating a semiconductor field-effect transistor (MOSFET) such as a strained Si n-MOSFET where dislocation or crystal defects spanning from source to drain is partially occupied by heavy p-type dopants. Preferably, the strained-layer n-MOSFET includes a Si, SiGe or SiGeC multi-layer structure having, in the region between source and drain, impurity atoms that preferentially occupy the dislocation sites so as to prevent shorting of source and drain via dopant diffusion along the dislocation. Advantageously, devices formed as a result of the invention are immune to dislocation-related failures, and therefore are more robust to processing and material variations. The invention thus relaxes the requirement for reducing the threading dislocation density in SiGe buffers, since the devices will be operable despite the presence of a finite number of dislocations.

Abstract: A structure and method of fabricating a high-mobility semiconductor layer structure and field-effect transistor (MODFET) that includes a high-mobility conducting channel, while at the same time, maintaining counter doping to control deleterious short-channel effects. The MODFET design includes a high-mobility conducting channel layer wherein the method allows the counter doping to be formed using a standard technique such as ion implantation, and further allows the high-mobility channel to be in close proximity to the counter doping without degradation of the mobility.

Abstract: An integrated optoelectronic circuit and process for making is described incorporating a photodetector and a MODFET on a chip. The chip contains a single-crystal semiconductor substrate, a buffer layer of SiGe graded in composition, a relaxed SiGe layer, a quantum well layer, an undoped SiGe spacer layer and a doped SiGe supply layer. The photodetector may be a metal-semiconductor-metal (MSM) or a p-i-n device. The detector may be integrated with an n- or p-type MODFET, or both in a CMOS configuration, and the MODFET can incorporate a Schottky or insulating gate. The invention overcomes the problem of producing Si-manufacturing-compatible monolithic high-speed optoelectronic circuits for 850 nm operation by using epixially-grown Si/SiGe heterostructure layers.