Varian Associates

About: Varian Associates is a based out in . It is known for research contribution in the topics: Beam (structure) & Wafer. The organization has 2160 authors who have published 2591 publications receiving 46002 citations.

Optoelectronic assembly including light transmissive single crystal semiconductor window

Abstract: An optoelectronic assembly obtains substantially improved coupling efficiency between small core optical fibers and small area detectors and emitters The assembly includes a housing containing an active optoelectronic device and a light transmissive single crystal semiconductor window The light transmissive single crystal semiconductor window seals the housing and physically protects the device from the environment The single crystal semiconductor window has an index of refraction higher than conventional glass windows, preferably greater than 2, in order to reduce beam spreading between the optical fiber and small area detectors or emitters The window material is preferably single crystal GaP

Fourier transform NMR spectroscopy employing a phase modulated rf carrier

Abstract: A nuclear magnetic resonance Fourier transform spectrometer includes a pulse modulated rf transmitter for delivering a train of radio frequency pulses having a pulse width pulse repetition rate to generate Fourier side bands to cover the spectral lines of the sample to be analyzed for exciting resonance of different resonance lines, if any, within the sample. Resonance of the sample is scanned in between successive transmitted pulses to obtain a multiplicity of successive time displaced components which are sampled and stored in a multiplicity of memory channels of a computer for time averaging thereof. The time averaged signal components are periodically read out and Fourier transformed to obtain a time averaged spectrum of the sample under analysis. Anomalous phase and intensity effects in the detected spectral lines are avoided by periodically shifting the phase of the pulse modulated carrier signal from one phase to another of at least three different relative phases in accordance with a predetermined sequence.

Structure and bonding in amorphous GexTe1−x alloys☆☆☆

Abstract: X-ray radial distribution studies of the system GexTe1−x have been interpreted in terms of a “random covalent” structural model. To further elucidate the structure and bonding type, X-ray absorption edge and X-ray photoemission studies were undertaken. Measured edge and photoemitted electron energies are consistent with covalent bonding. For x = 0.15 to 0.57, the Ge Kα edge and the Ge 3d 5 2 photo-emitted electron energies of the amorphous materials are close to those of crystalline Ge. For crystalline GeTe, GeSe and GeS, there are 2 to 3 eV shifts indicative of more ionic binding. These results imply that the amorphous materials are considerably more covalent than any of the crystalline Ge-chalcogenide phases and suggest that none of the crystalline structures can form the basis for a microcrystalline picture of amorphous GeTe.

Multi-gap magnetic imaging lens for charged particle beams

Abstract: A magnetic lens for imaging and rotation of a charged particle beam includes a pair of focus elements axially spaced along a lens bore through which the beam passes and a rotation element positioned axially between the focus elements. Each of the lens elements includes a polepiece having opposing portions surrounding the lens bore and axially spaced apart to define a circumferential gap, and a winding for energizing the polepiece and the gap. The focus elements are energized by equal and opposite magnetic fields which focus the electron beam without substantial beam rotation. The beam can be rotated, without substantial change in focus or magnification, by varying the magnetic field of the rotation element. The lens is particularly suited for use in a shaped electron beam lithography system.