Other

Arizona State University

Tokyo Electron Limited

Arizona Board of Regents, a Body Corporate

Shane R Johnson

J Thomas Tiedje

Yong-Hang Zhang

Christian Lavoie

Mark K Nissen

Wayne L Johnson

Wolfgang Braun

Rajeev Reddy Kosireddy

Stephen T Schaefer

Philip Dowd

Chaturvedi Gogineni

Chang-Zhi Guo

Preston T Webster

Nathaniel A Riordan

Ankur R Sharma

Marko S Milosavljevic

The invention relates in part to a growth model for the growth of Group III-Group V (III-V) alloys by molecular beam epitaxy (MBE) based on the kinetics of adsorption, desorption, incorporation, anion exchange, anion-assisted removal, and surface droplet accumulation of the Group V elements. The invention also relates to methods to optimize MBE growth conditions used to produce a target III-V alloy composition. The invention is further related to methods of predicting III-V alloy compositions resulting from a set of MBE growth conditions.

Kinetic model for molecular beam epitaxy growth of III-V bismide alloys

Optical devices based on bismuth-containing III-V compound semiconductor materials are disclosed. The optical device includes an optically active pseudomorphic superlattice formed on a substrate. The superlattice includes alternating InAsSblayers (where y is greater than or equal to zero) and InAsBi layers.

Optical device based on bismuth-containing III-V compound multilayer semiconductors

An apparatus () using specular reflection spectroscopy to measure a temperature of a substrate (). By reflecting light () from a substrate, the temperature of the substrate can be determined using the band-edge characteristics of the substrate. This in situ apparatus can be used as a feedback control in combination with a variable temperature substrate holder to more accurately control the processing conditions of the substrate. By utilizing a multiplicity of measurement sites, the variation of the temperature across the substrate can also be measured.

Apparatus for measuring temperatures of a wafer using specular reflection spectroscopy

The invention discloses improved structures of light-processing (e.g. light-emitting and light-absorbing/sensing) devices, in particular Vertical Cavity Surface Emitting Lasers (VCSELs), such as may find use in telecommunications applications. The disclosed VSCAL devices and production methods provide for an active region having a quantum well structure grown on GaAs-containing substrates, thus providing processing compatibility for light having wavelength in the range 1.0 to 1.6 &#x3bc;m. The active region structure combines strain-compensating barriers with different band alignments in the quantum wells to achieve a long emission wavelength while at the same time decreasing the strain in the structure. The improved functioning of the devices disclosed results from building them with multicomponent alloy layers having a large number of constituents. The invention discloses as a key constituent in the proposed alloy layers for the active region a substance, such as nitrogen (N), suitable for reducing bandgap energy (i.e., increasing light wavelength) associated with the layers while at the same time lowering the lattice constant associated with the structure and hence lowering strain.

Long wavelength pseudomorphic InGaNPAsSb type-I and type-II active layers for the gaas material system

An optical method for measuring the temperature of a substrate material with a temperature dependent band edge. In this method both the position and the width of the knee of the band edge spectrum of the substrate are used to determine temperature. The width of the knee is used to correct for the spurious shifts in the position of the knee caused by: (i) thin film interference in a deposited layer on the substrate; (ii) anisotropic scattering at the back of the substrate; (iii) the spectral variation in the absorptance of deposited layers that absorb in the vicinity of the band edge of the substrate; and (iv) the spectral dependence in the optical response of the wavelength selective detection system used to obtain the band edge spectrum of the substrate. The adjusted position of the knee is used to calculate the substrate temperature from a predetermined calibration curve. This algorithm is suitable for real-time applications as the information needed to correct the knee position is obtained from the spectrum itself. Using a model for the temperature dependent shape of the absorption edge in GaAs and InP, the effect of substrate thickness and the optical geometry of the method used to determine the band edge spectrum, are incorporated into the calibration curve.

Method for determining the temperature of semiconductor substrates from

An optical method for measuring the temperature of a substrate material with a temperature dependent bandgap. The substrate is illuminated with a broad spectrum lamp and the bandgap is determined from the spectrum of the diffusely scattered light. The spectrum of the light from the lamp is sufficiently broad that it covers the spectral range above and below the bandgap of the substrate. Wavelengths corresponding to photon energies less than the bandgap of the substrate are transmitted through the substrate and are reflected from the back surface of the substrate as well as from the front surface while the wavelengths corresponding to photon energies larger than the bandgap are reflected only from the front surface. If the front surface is polished the front surface reflection will be specular while if the back surface is rough the reflection from the back surface will be non-specular. The back surface reflection is detected with a detector in a non-specular location. From the wavelength of the onset of the non-specular reflection the bandgap can be determined which gives the temperature. The temperature is determined from the knee in the diffuse reflectance spectrum near the bandgap.

Optical apparatus and method for measuring temperature of a substrate

An optical method and apparatus for measuring the temperature of a substrate material with a temperature dependent bandgap. The substrate is illuminated with a broad spectrum lamp and the bandgap is determined from the spectrum of the diffusely scattered light. The spectrum of the light from the lamp is sufficiently broad that it covers the spectral range above and below the bandgap of the substrate. Wavelengths corresponding to photon energies less than the bandgap of the substrate are transmitted through the substrate and are reflected from the back surface of the substrate as well as from the front surface while the wavelengths corresponding to photon energies larger than the bandgap are reflected only from the front surface. If the front surface is polished the front surface reflection will be specular while if the back surface is rough the reflection from the back surface will be non-specular. The back surface reflection is detected with a detector in a non-specular location. From the wavelength of the onset of the non-specular reflection the bandgap can be determined which gives the temperature. The temperature is determined from the knee in the diffuse reflectance spectrum near the bandgap.

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Chandler, AZ, United States of America

Shane R Johnson