Arizona State University

United States of America As Represented by the Secretary of the Air Force

Arizona Board of Regents, a Body Corporate

Jose Menendez

John Kouvetakis

John Tolle

Richard A Soref

Rodolfo Enrique Diaz

Dean Samara-Rubio

Ling Liao

Ampere A Tseng

Ignatius S T Tsong

Sethuraman Panchanathan

Matthew Bauer

Karl S Booksh

Chang Wu Hu

Michael Wagner

A method for depositing an epitaxial Ge&#x2014;Sn layer on a substrate in a CVD reaction chamber includes introducing into the chamber a gaseous precursor comprising SnD4 under conditions whereby the epitaxial Ge&#x2014;Sn layer is formed on the substrate. the gaseous precursor comprises SnD4 and high purity H2 of about 15-20% by volume. The gaseous precursor is introduced at a temperature in a range of about 250&#xb0; C. to about 350&#xb0; C. Using the process device-quality Sn&#x2014;Ge materials with tunable bandgaps can be grown directly on Si substrates.

GeSn alloys and ordered phases with direct tunable bandgaps grown directly on silicon

Semiconductor structures having at least one quantum well heterostructure grown strain-free on Si(100) via a SnGebuffer layer and their uses are provided.

Materials and optical devices based on group IV quantum wells grown on Si-Ge-Sn buffered silicon

Methods and apparatus for gathering image information from nanostructures includes a composite waveguide of conductive nanoparticles in a dielectric medium. The waveguide is irradiated with preferably coherent blue light to form a slow surface wave. The evanescent wave that is the 'tail' of the surface wave exists outside the waveguide contiguous to its surface. The nanostructures are located to encounter the evanescent wave. The slowing of the wave that occurs in the waveguide reduces the wave's speed and wavelength sufficiently such that nanostructures can be imaged. Upon encountering the evanescent wave, the nanostructures radiate. This radiation causes a backward scattering from the structures and a forward perturbation of the wavefront of the surface wave. From the scattering and perturbation information about the physical characteristics of the nanostructures sufficient to form an image is derived.

Coherent evanescent wave imaging

This invention teaches two new families of Si-based Ge/SnGeheterodiode and multiple quantum well (MQW) photonic devices: (1) band-to-band photodetectors, lasers, emitters, amplifiers and modulators for the 1.5 to 12 &#x3bc;m wavelength range; (2) intersubband photodetectors, lasers, emitters and modulators for 12 to 100 &#x3bc;m operation. The bipolar band-to-band devices have applications within the 1.5-2.2, 3-5 and 8-to-12 &#x3bc;m bands. The unipolar intersubband group has longwave infrared and terahertz applications. All strained-layer devices are grown a relaxed SnSiGebuffer layer&#x2014;a virtual substrate (VS) grown directly upon a silicon wafer by unique LT UHV-CVD. The VS provides a low-defect atomic template for subsequent heteroepitaxy and is an essential enabling technique for engineering tensile and compressive strain within the Ge/SnGeMQW by selecting the VS lattice parameter to be approx midway between the layer lattices.

Strain-engineered direct-gap Ge/SnxGe1-x heterodiode and multi-quantum-well photodetectors, laser, emitters and modulators grown on SnySizGe1-y-z-buffered silicon

Growing community of inventors

Tempe, AZ, United States of America

Jose Menendez