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

Sigma-aldrich Co. LLC

David W Weyburne

Brian S Ahern

David F Bliss

Candace Lynch

Rajesh Odedra

Ravi Kanjolia

Harry R Clark

Michael R Snure

Gerald W Iseler

Neil Boag

Qing S Paduano

Qing Sun-Paduano

A low pressure process for producing thin film crystalline black phosphorus on a substrate and a black phosphorus thin film made by the process. The process includes flowing a phosphorus-containing gas into a deposition chamber and depositing phosphorus from the phosphorus-containing gas onto the substrate in the chamber. The substrate is selected from (i) a gold substrate, a gold-tin alloy substrate, a silver substrate and a copper substrate and (ii) a substrate comprising a thin film of metal selected from gold, tin, silver, copper and alloys of the foregoing metals. The substrate and phosphorus are heated to a temperature ranging from about 350&#xb0; to less than about 500&#xb0; C. to form a phosphorus intermediate composition. The substrate and intermediate composition are heated to a temperature of greater than 500&#xb0; C. to less than about 1000&#xb0; C. convert the metal phosphorus intermediate composition to the black phosphorus thin film.

Method and apparatus for producing a nanometer thick film of black phosphorus

A new method for making a nonlinear optical structure for frequency conversion and for using that structure for frequency conversion is described. The nonlinear optical structure is made by depositing alternating contiguous layers of gallium arsenide and aluminum gallium arsenide onto a gallium arsenide substrate. Optical frequency conversion is performed by transmitting a pump laser beam through the structure. The new method is easier to perform than prior art methods.

Multi-layer gallium arsenide-based fresnel phase-shift device for infrared wavelength conversion

Methods of forming thin metal-containing films by chemical phase deposition, particularly atomic layer deposition (ALD) and chemical vapor deposition (CVD), are provided. The methods comprise delivering at least one organometallic precursor to a substrate, wherein the at least one precursor corresponds in structure to Formula (II); wherein: M is Ru, Fe or Os; R is Q-C-alkyl; X is C-C-alkyl; and n is zero, 1, 2, 3, 4 or 5. Further provided are methods of making precursors disclosed herein.

Methods of forming thin metal-containing films by chemical phase deposition

A new nonlinear optical structure for frequency conversion is described. The new nonlinear optical structure is a multilayer wafer comprising alternating layers of gallium arsenide and aluminum gallium arsenide onto a gallium arsenide substrate. The new device is both more efficient and easier to make than prior art gallium arsenide crystal structures designed for nonlinear optical conversion.

A spin coating apparatus and method of manufacturing incorporating a perforated sheet located above the substrate in a manner to control solvent evaporation that tends to occur in the coating vessel when the chuck is rotated without introducing additional airflow complications. The distance between the substrate surface and the perforated sheet, and the number, distribution, and size of the perforations in the perforated sheet can be adjusted to optimize the uniformity of film thickness coating the substrate. The result is reduced substrate and room contamination and enhanced coating uniformity.

Spin coating of substrate with chemical

This invention is a process and apparatus for producing single crystal, polycrystal or amorphous stand-alone films. The process has two steps: First, thin layers of the desired materials are deposited by VD onto a hot foreign single crystal substrate wafer held by a substrate platter in a pocket formed in such. The second step is to chemically etch away the substrate while still being held by the substrate platter while the film-substrate is still hot. The etch is stopped as soon as all of the foreign substrate is consumed. This leaves just the thin film which is then cooled down to room temperature. The bottom surface of this pocket has a plurality of channels for carrying an etching gas which is input by a central channel in the substrate platter. The reactants that form the stand-alone film are input through an actively cooled effusion cell having a plenum for receiving the reactant gas. The reactant gas flows past a plurality of parallel spaced-apart tubes having a coolant therein onto the heated substrate surface which is in very close proximity to the coolant tubes. The thin films can be deposited by any of the various VD methods such as plasma assisted CVD and D.C. or RF sputtering.

VD process and apparatus for producing stand-alone thin films

The invention works by taking optical reflectance measurements on the deposited layers at different wavelengths and fitting the measured results to extract the thicknesses and compositions. The process of the present invention simultaneously measures the thicknesses of elemental and binary semiconductors' layers and the thicknesses and composition of ternary layers. Highly precise thickness and composition estimates and wafer maps of the growth rates and composition are provided by (1) measuring in a wavelength range at which the index of refractions are rapidly varying and (2) growing a special high reflectance test structure consisting of alternating layers of the materials to be measured.

Process for measuring the thickness and composition of thin

A wafer cutting device has a plurality of individually highly tensioned diamond impregnated wires that are mounted in a translatable head. Each wire has a tension monitor connected thereto for the purpose of insuring uniform tension and also alerting to breakage. Further, a differential DC voltage is applied to the wires and the crystal with the assistance of electrolytes to improve the removal of material for minimizing damage to the surfaces. The crystal is mounted on a two dimensional stage. During normal cutting the crystal is moved vertically into the cutting wire. The vertical cutting rate is adjusted due to the configuration of the crystal. At the end of cutting, the crystal is moved laterally so as to place a notch in the wafers for the purpose of removing the wafer in a clean break.

Wafer cutting device

An actively cooled effuser for a vapor deposition reactor is placed in very close proximity to a substrate. The actively cooled effuser has combinations of gas directing plates, cooling plates and isolation plates attached together. Reactants and coolant are input into the stack of plates so formed. Selective heating of the substrate surface may occur through the use of heating lamps. Multiple units of the actively cooled effuser and heating lamps may be used in the reactor to form multiple layers on the substrate. The cooling plate has a cooling channel within a few thousandths of an inch of the output side of the stack. The presence of the cooling plates allows the effuser to be placed in very close proximity to the selectively heated substrate.

Chemical vapor deposition method using an actively cooled effuser to

The present invention is a heat pipe susceptor for use in a vapor deposition system. The multi-layered refractory material susceptor provides a highly uniform heated surface upon which wafers are placed for heating by a radio frequency (RF) source. Because of the highly uniform surface temperature, susceptors are able to hold a plurality of inch sized diameter wafers and the shape of the surfaces can be designed as the need arises. A cylindrically shaped top and a multi-faced frustum shaped top are examples.

Heat pipe susceptor for epitaxy

Actively cooled effusion cell for chemical vapor deposition

A high emissivity cold cathode has alternating cylindrical tube layers, deposited by vapor deposition, of a refractory metal such as niobium and a refractory insulating material such as alumina. The metal layers have a thickness of less than or about 1,000 angstroms such that the electric field strength at the exposed end is sufficient, in combination with a low work function metal to emit electrons when a voltage of about 2,000 volts is applied.

High emissivity cold cathode ultrastructure

A static periodic field device for a free electron laser has a plurality of holes therethrough to allow the interaction of electrons flowing therethrough to interact with either an electric or a magnetic fields as desired. The device is composed of a plurality of conducting layers separated by insulating layers and appropriately connected to provide either an electric or a magnetic field therein. The separation of the conducting layers determines the raidated energy wavelength.

Static periodic field device for free electron laser

A metal organic chemical vapor deposition reactor 10 which includes a flat plate flow channel gas delivery system 18. The gas delivery system comprises slotted rods 40, 42 which pass through an assembly 46 of seal plates 52 and gas directing plates 50. Gas directing plates 52 provide separate flow channels for reactant gases in rods 40 and 42. Reactants are directly jetted from the gas directing plates onto a substrate 20 prior to mixing.

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Maynard, MA, United States of America

David W Weyburne