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.

Pattern data handling system for an electron beam exposure system

Abstract: A pattern data handling system for an electron beam exposure system wherein figure data conversion is performed simultaneously with irradiation of a workpiece, thereby providing high speed operation Figure data, containing figure descriptions for a stripe area, is subdivided into blocks of segment figure data and is stored in a pattern data memory Multiple pattern generators, each including a bit map memory, simultaneously convert blocks of segment figure data to bit maps and store the bit maps in their respective bit map memories The bit maps are transferred out of the bit map memories and through a shift register one at a time to provide continuous beam blanking data The system is particularly useful for electron beam exposure of reticles which are characterized by little or no repetition of features and by relatively large features

Collimation system for electron arc therapy

Abstract: An electron collimation system for electron arc therapy treatments consists of a slit collimation system which is movable with the electron beam applicator and is designed to allow for dose compensation in the sagittal direction and a hoop-and-clamp assembly for final field shaping. By correctly designing the shape of the slit in the former and properly adjusting the components of the latter, it is possible to accomplish quite uniform shielding without causing any weight of the shielding material to rest on the patient.

Improved photoemitters using GaAs and InGaAs

Abstract: A luminous sensitivity of 900 µA/lm in a GaAs-Cs-O photocathode, and a photothreshold of 1.16 eV in an InGaAs photocathode with Cs-O or Cs-H 2 O surface layers, are reported.

Landau Levels and Magneto-Absorption in InSb

Abstract: Detailed results are presented of machine calculations of the Landau level structure and transition matrix elements for InSb near the center of the Brillouin zone, for magnetic fields in the [100] direction, and under conditions typical of valence-band cyclotron resonance and interband magneto-optical experiments. Effects of inversion asymmetry arising in the zinc-blende structure are included. The theoretical conduction-band combinational resonance spectra of Rashba and Sheka are confirmed and extended to the nonparabolic-band model. The results show good agreement with the recent interband magneto-optical observations by Pidgeon and Brown. Different heavy hole "masses" are predicted for valence-band cyclotron resonance under different experimental conditions. Some of these coincide with reported experimental results. Details of the predicted spin-split zero-field band structure in the (110) plane are given.